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linux/arch/powerpc/kernel/entry_64.S

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powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
/*
* PowerPC version
* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
* Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP
* Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu>
* Adapted for Power Macintosh by Paul Mackerras.
* Low-level exception handlers and MMU support
* rewritten by Paul Mackerras.
* Copyright (C) 1996 Paul Mackerras.
* MPC8xx modifications Copyright (C) 1997 Dan Malek (dmalek@jlc.net).
*
* This file contains the system call entry code, context switch
* code, and exception/interrupt return code for PowerPC.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/errno.h>
#include <asm/unistd.h>
#include <asm/processor.h>
#include <asm/page.h>
#include <asm/mmu.h>
#include <asm/thread_info.h>
#include <asm/ppc_asm.h>
#include <asm/asm-offsets.h>
#include <asm/cputable.h>
[POWERPC] implement BEGIN/END_FW_FTR_SECTION and use it an all the obvious places in assembler code. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
2006-09-25 10:19:00 +02:00
#include <asm/firmware.h>
[POWERPC] Fix manual assembly WARN_ON() in enter_rtas(). When we switched over to the generic BUG mechanism we forgot to change the assembly code which open-codes a WARN_ON() in enter_rtas(), so the bug table got corrupted. This patch provides an EMIT_BUG_ENTRY macro for use in assembly code, and uses it in entry_64.S. Tested with CONFIG_DEBUG_BUGVERBOSE on ppc64 but not without -- I tried to turn it off but it wouldn't go away; I suspect Aunt Tillie probably needed it. This version gets __FILE__ and __LINE__ right in the assembly version -- rather than saying include/asm-powerpc/bug.h line 21 every time which is a little suboptimal. Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-01-01 19:45:34 +01:00
#include <asm/bug.h>
[POWERPC] Move stackframe definitions to common header This moves various definitions used all over the place to parse stack frames to ptrace.h so only one definition is needed. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-17 06:34:59 +02:00
#include <asm/ptrace.h>
[POWERPC] irqtrace support for 64-bit powerpc This adds the low level irq tracing hooks to the powerpc architecture needed to enable full lockdep functionality. This is partly based on Johannes Berg's initial version. I removed the asm trampoline that isn't needed (thus improving performance) and modified all sorts of bits and pieces, reworking most of the assembly, etc... Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-17 06:35:01 +02:00
#include <asm/irqflags.h>
ftrace: store mcount address in rec->ip Record the address of the mcount call-site. Currently all archs except sparc64 record the address of the instruction following the mcount call-site. Some general cleanups are entailed. Storing mcount addresses in rec->ip enables looking them up in the kprobe hash table later on to check if they're kprobe'd. Signed-off-by: Abhishek Sagar <sagar.abhishek@gmail.com> Cc: davem@davemloft.net Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-21 20:17:27 +02:00
#include <asm/ftrace.h>
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 08:27:59 +01:00
#include <asm/hw_irq.h>
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
/*
* System calls.
*/
.section ".toc","aw"
.SYS_CALL_TABLE:
.tc .sys_call_table[TC],.sys_call_table
/* This value is used to mark exception frames on the stack. */
exception_marker:
[POWERPC] Move stackframe definitions to common header This moves various definitions used all over the place to parse stack frames to ptrace.h so only one definition is needed. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-17 06:34:59 +02:00
.tc ID_EXC_MARKER[TC],STACK_FRAME_REGS_MARKER
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
.section ".text"
.align 7
#undef SHOW_SYSCALLS
.globl system_call_common
system_call_common:
andi. r10,r12,MSR_PR
mr r10,r1
addi r1,r1,-INT_FRAME_SIZE
beq- 1f
ld r1,PACAKSAVE(r13)
1: std r10,0(r1)
std r11,_NIP(r1)
std r12,_MSR(r1)
std r0,GPR0(r1)
std r10,GPR1(r1)
powerpc: Implement accurate task and CPU time accounting This implements accurate task and cpu time accounting for 64-bit powerpc kernels. Instead of accounting a whole jiffy of time to a task on a timer interrupt because that task happened to be running at the time, we now account time in units of timebase ticks according to the actual time spent by the task in user mode and kernel mode. We also count the time spent processing hardware and software interrupts accurately. This is conditional on CONFIG_VIRT_CPU_ACCOUNTING. If that is not set, we do tick-based approximate accounting as before. To get this accurate information, we read either the PURR (processor utilization of resources register) on POWER5 machines, or the timebase on other machines on * each entry to the kernel from usermode * each exit to usermode * transitions between process context, hard irq context and soft irq context in kernel mode * context switches. On POWER5 systems with shared-processor logical partitioning we also read both the PURR and the timebase at each timer interrupt and context switch in order to determine how much time has been taken by the hypervisor to run other partitions ("steal" time). Unfortunately, since we need values of the PURR on both threads at the same time to accurately calculate the steal time, and since we can only calculate steal time on a per-core basis, the apportioning of the steal time between idle time (time which we ceded to the hypervisor in the idle loop) and actual stolen time is somewhat approximate at the moment. This is all based quite heavily on what s390 does, and it uses the generic interfaces that were added by the s390 developers, i.e. account_system_time(), account_user_time(), etc. This patch doesn't add any new interfaces between the kernel and userspace, and doesn't change the units in which time is reported to userspace by things such as /proc/stat, /proc/<pid>/stat, getrusage(), times(), etc. Internally the various task and cpu times are stored in timebase units, but they are converted to USER_HZ units (1/100th of a second) when reported to userspace. Some precision is therefore lost but there should not be any accumulating error, since the internal accumulation is at full precision. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-02-24 00:06:59 +01:00
ACCOUNT_CPU_USER_ENTRY(r10, r11)
powerpc: Fix system calls on Cell entered with XER.SO=1 It turns out that on Cell, on a kernel with CONFIG_VIRT_CPU_ACCOUNTING = y, if a program sets the SO (summary overflow) bit in the XER and then does a system call, the SO bit in CR0 will be set on return regardless of whether the system call detected an error. Since CR0.SO is used as the error indication from the system call, this means that all system calls appear to fail. The reason is that the workaround for the timebase bug on Cell uses a compare instruction. With CONFIG_VIRT_CPU_ACCOUNTING = y, the ACCOUNT_CPU_USER_ENTRY macro reads the timebase, so we end up doing a compare instruction, which copies XER.SO to CR0.SO. Since we were doing this in the system call entry patch after clearing CR0.SO but before saving the CR, this meant that the saved CR image had CR0.SO set if XER.SO was set on entry. This fixes it by moving the clearing of CR0.SO to after the ACCOUNT_CPU_USER_ENTRY call in the system call entry path. Signed-off-by: Paul Mackerras <paulus@samba.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-11-30 12:49:45 +01:00
/*
* This "crclr so" clears CR0.SO, which is the error indication on
* return from this system call. There must be no cmp instruction
* between it and the "mfcr r9" below, otherwise if XER.SO is set,
* CR0.SO will get set, causing all system calls to appear to fail.
*/
crclr so
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
std r2,GPR2(r1)
std r3,GPR3(r1)
std r4,GPR4(r1)
std r5,GPR5(r1)
std r6,GPR6(r1)
std r7,GPR7(r1)
std r8,GPR8(r1)
li r11,0
std r11,GPR9(r1)
std r11,GPR10(r1)
std r11,GPR11(r1)
std r11,GPR12(r1)
powerpc: No need to save XER in a system call The XER is a volatile register so there is no need to save and restore it over a system call - zero it out in the exception stack frame instead. This should fix a 5 cycle stall of the mfxer/std seen on POWER7. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-04-04 20:24:29 +02:00
std r11,_XER(r1)
powerpc: No need to preserve count register across system call The count register is volatile so we don't need to preserve it. Store zero to the entry in the exception frame. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-04-04 20:26:39 +02:00
std r11,_CTR(r1)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
std r9,GPR13(r1)
mfcr r9
mflr r10
li r11,0xc01
std r9,_CCR(r1)
std r10,_LINK(r1)
std r11,_TRAP(r1)
std r3,ORIG_GPR3(r1)
ld r2,PACATOC(r13)
addi r9,r1,STACK_FRAME_OVERHEAD
ld r11,exception_marker@toc(r2)
std r11,-16(r9) /* "regshere" marker */
powerpc: Account time using timebase rather than PURR Currently, when CONFIG_VIRT_CPU_ACCOUNTING is enabled, we use the PURR register for measuring the user and system time used by processes, as well as other related times such as hardirq and softirq times. This turns out to be quite confusing for users because it means that a program will often be measured as taking less time when run on a multi-threaded processor (SMT2 or SMT4 mode) than it does when run on a single-threaded processor (ST mode), even though the program takes longer to finish. The discrepancy is accounted for as stolen time, which is also confusing, particularly when there are no other partitions running. This changes the accounting to use the timebase instead, meaning that the reported user and system times are the actual number of real-time seconds that the program was executing on the processor thread, regardless of which SMT mode the processor is in. Thus a program will generally show greater user and system times when run on a multi-threaded processor than on a single-threaded processor. On pSeries systems on POWER5 or later processors, we measure the stolen time (time when this partition wasn't running) using the hypervisor dispatch trace log. We check for new entries in the log on every entry from user mode and on every transition from kernel process context to soft or hard IRQ context (i.e. when account_system_vtime() gets called). So that we can correctly distinguish time stolen from user time and time stolen from system time, without having to check the log on every exit to user mode, we store separate timestamps for exit to user mode and entry from user mode. On systems that have a SPURR (POWER6 and POWER7), we read the SPURR in account_system_vtime() (as before), and then apportion the SPURR ticks since the last time we read it between scaled user time and scaled system time according to the relative proportions of user time and system time over the same interval. This avoids having to read the SPURR on every kernel entry and exit. On systems that have PURR but not SPURR (i.e., POWER5), we do the same using the PURR rather than the SPURR. This disables the DTL user interface in /sys/debug/kernel/powerpc/dtl for now since it conflicts with the use of the dispatch trace log by the time accounting code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-26 21:56:43 +02:00
#if defined(CONFIG_VIRT_CPU_ACCOUNTING) && defined(CONFIG_PPC_SPLPAR)
BEGIN_FW_FTR_SECTION
beq 33f
/* if from user, see if there are any DTL entries to process */
ld r10,PACALPPACAPTR(r13) /* get ptr to VPA */
ld r11,PACA_DTL_RIDX(r13) /* get log read index */
ld r10,LPPACA_DTLIDX(r10) /* get log write index */
cmpd cr1,r11,r10
beq+ cr1,33f
bl .accumulate_stolen_time
REST_GPR(0,r1)
REST_4GPRS(3,r1)
REST_2GPRS(7,r1)
addi r9,r1,STACK_FRAME_OVERHEAD
33:
END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR)
#endif /* CONFIG_VIRT_CPU_ACCOUNTING && CONFIG_PPC_SPLPAR */
powerpc: Improve 64-bit syscall entry/exit We unconditionally hard enable interrupts. This is unnecessary as syscalls are expected to always be called with interrupts enabled. While at it, we add a WARN_ON if that is not the case and CONFIG_TRACE_IRQFLAGS is enabled (we don't want to add overhead to the fast path when this is not set though). Thus let's remove the enabling (and associated irq tracing) from the syscall entry path. Also on Book3S, replace a few mfmsr instructions with loads of PACAMSR from the PACA, which should be faster & schedule better. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-01 05:40:23 +01:00
/*
* A syscall should always be called with interrupts enabled
* so we just unconditionally hard-enable here. When some kind
* of irq tracing is used, we additionally check that condition
* is correct
*/
#if defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_BUG)
lbz r10,PACASOFTIRQEN(r13)
xori r10,r10,1
1: tdnei r10,0
EMIT_BUG_ENTRY 1b,__FILE__,__LINE__,BUGFLAG_WARNING
#endif
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#ifdef CONFIG_PPC_BOOK3E
wrteei 1
#else
powerpc: Improve 64-bit syscall entry/exit We unconditionally hard enable interrupts. This is unnecessary as syscalls are expected to always be called with interrupts enabled. While at it, we add a WARN_ON if that is not the case and CONFIG_TRACE_IRQFLAGS is enabled (we don't want to add overhead to the fast path when this is not set though). Thus let's remove the enabling (and associated irq tracing) from the syscall entry path. Also on Book3S, replace a few mfmsr instructions with loads of PACAMSR from the PACA, which should be faster & schedule better. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-01 05:40:23 +01:00
ld r11,PACAKMSR(r13)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
ori r11,r11,MSR_EE
mtmsrd r11,1
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#endif /* CONFIG_PPC_BOOK3E */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
powerpc: Improve 64-bit syscall entry/exit We unconditionally hard enable interrupts. This is unnecessary as syscalls are expected to always be called with interrupts enabled. While at it, we add a WARN_ON if that is not the case and CONFIG_TRACE_IRQFLAGS is enabled (we don't want to add overhead to the fast path when this is not set though). Thus let's remove the enabling (and associated irq tracing) from the syscall entry path. Also on Book3S, replace a few mfmsr instructions with loads of PACAMSR from the PACA, which should be faster & schedule better. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-01 05:40:23 +01:00
/* We do need to set SOFTE in the stack frame or the return
* from interrupt will be painful
*/
li r10,1
std r10,SOFTE(r1)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
#ifdef SHOW_SYSCALLS
bl .do_show_syscall
REST_GPR(0,r1)
REST_4GPRS(3,r1)
REST_2GPRS(7,r1)
addi r9,r1,STACK_FRAME_OVERHEAD
#endif
clrrdi r11,r1,THREAD_SHIFT
ld r10,TI_FLAGS(r11)
andi. r11,r10,_TIF_SYSCALL_T_OR_A
bne- syscall_dotrace
powerpc: Hide some system call labels from profile tools syscall_dotrace_cont and syscall_error_cont tend to complicate perf output so make them local. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-04-04 20:23:27 +02:00
.Lsyscall_dotrace_cont:
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
cmpldi 0,r0,NR_syscalls
bge- syscall_enosys
system_call: /* label this so stack traces look sane */
/*
* Need to vector to 32 Bit or default sys_call_table here,
* based on caller's run-mode / personality.
*/
ld r11,.SYS_CALL_TABLE@toc(2)
andi. r10,r10,_TIF_32BIT
beq 15f
addi r11,r11,8 /* use 32-bit syscall entries */
clrldi r3,r3,32
clrldi r4,r4,32
clrldi r5,r5,32
clrldi r6,r6,32
clrldi r7,r7,32
clrldi r8,r8,32
15:
slwi r0,r0,4
ldx r10,r11,r0 /* Fetch system call handler [ptr] */
mtctr r10
bctrl /* Call handler */
syscall_exit:
[PATCH] syscall entry/exit revamp This cleanup patch speeds up the null syscall path on ppc64 by about 3%, and brings the ppc32 and ppc64 code slightly closer together. The ppc64 code was checking current_thread_info()->flags twice in the syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after disabling interrupts. Now we do the same as ppc32 -- check the flags only once in the fast path, and re-enable interrupts if necessary in the ptrace case. The patch abolishes the 'syscall_noerror' member of struct thread_info and replaces it with a TIF_NOERROR bit in the flags, which is handled in the slow path. This shortens the syscall entry code, which no longer needs to clear syscall_noerror. The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow path to save the non-volatile GPRs into a signal frame. This removes the need for the assembly wrappers around sys_sigsuspend(), sys_rt_sigsuspend(), et al which existed solely to save those registers in advance. It also means I don't have to add new wrappers for ppoll() and pselect(), which is what I was supposed to be doing when I got distracted into this... Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit directly into a signal handler (as required by sigsuspend et al) by introducing a TIF_RESTOREALL flag which causes _all_ the registers to be reloaded from the pt_regs by taking the ret_from_exception path, instead of the normal syscall exit path which stomps on the callee-saved GPRs. It appears to pass an LTP test run on ppc64, and passes basic testing on ppc32 too. Brief tests of ptrace functionality with strace and gdb also appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-15 19:52:18 +01:00
std r3,RESULT(r1)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
#ifdef SHOW_SYSCALLS
bl .do_show_syscall_exit
[PATCH] syscall entry/exit revamp This cleanup patch speeds up the null syscall path on ppc64 by about 3%, and brings the ppc32 and ppc64 code slightly closer together. The ppc64 code was checking current_thread_info()->flags twice in the syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after disabling interrupts. Now we do the same as ppc32 -- check the flags only once in the fast path, and re-enable interrupts if necessary in the ptrace case. The patch abolishes the 'syscall_noerror' member of struct thread_info and replaces it with a TIF_NOERROR bit in the flags, which is handled in the slow path. This shortens the syscall entry code, which no longer needs to clear syscall_noerror. The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow path to save the non-volatile GPRs into a signal frame. This removes the need for the assembly wrappers around sys_sigsuspend(), sys_rt_sigsuspend(), et al which existed solely to save those registers in advance. It also means I don't have to add new wrappers for ppoll() and pselect(), which is what I was supposed to be doing when I got distracted into this... Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit directly into a signal handler (as required by sigsuspend et al) by introducing a TIF_RESTOREALL flag which causes _all_ the registers to be reloaded from the pt_regs by taking the ret_from_exception path, instead of the normal syscall exit path which stomps on the callee-saved GPRs. It appears to pass an LTP test run on ppc64, and passes basic testing on ppc32 too. Brief tests of ptrace functionality with strace and gdb also appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-15 19:52:18 +01:00
ld r3,RESULT(r1)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
#endif
clrrdi r12,r1,THREAD_SHIFT
ld r8,_MSR(r1)
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#ifdef CONFIG_PPC_BOOK3S
/* No MSR:RI on BookE */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
andi. r10,r8,MSR_RI
beq- unrecov_restore
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#endif
powerpc: Improve 64-bit syscall entry/exit We unconditionally hard enable interrupts. This is unnecessary as syscalls are expected to always be called with interrupts enabled. While at it, we add a WARN_ON if that is not the case and CONFIG_TRACE_IRQFLAGS is enabled (we don't want to add overhead to the fast path when this is not set though). Thus let's remove the enabling (and associated irq tracing) from the syscall entry path. Also on Book3S, replace a few mfmsr instructions with loads of PACAMSR from the PACA, which should be faster & schedule better. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-01 05:40:23 +01:00
/*
* Disable interrupts so current_thread_info()->flags can't change,
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
* and so that we don't get interrupted after loading SRR0/1.
*/
#ifdef CONFIG_PPC_BOOK3E
wrteei 0
#else
powerpc: Improve 64-bit syscall entry/exit We unconditionally hard enable interrupts. This is unnecessary as syscalls are expected to always be called with interrupts enabled. While at it, we add a WARN_ON if that is not the case and CONFIG_TRACE_IRQFLAGS is enabled (we don't want to add overhead to the fast path when this is not set though). Thus let's remove the enabling (and associated irq tracing) from the syscall entry path. Also on Book3S, replace a few mfmsr instructions with loads of PACAMSR from the PACA, which should be faster & schedule better. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-01 05:40:23 +01:00
ld r10,PACAKMSR(r13)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
mtmsrd r10,1
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#endif /* CONFIG_PPC_BOOK3E */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
ld r9,TI_FLAGS(r12)
[PATCH] syscall entry/exit revamp This cleanup patch speeds up the null syscall path on ppc64 by about 3%, and brings the ppc32 and ppc64 code slightly closer together. The ppc64 code was checking current_thread_info()->flags twice in the syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after disabling interrupts. Now we do the same as ppc32 -- check the flags only once in the fast path, and re-enable interrupts if necessary in the ptrace case. The patch abolishes the 'syscall_noerror' member of struct thread_info and replaces it with a TIF_NOERROR bit in the flags, which is handled in the slow path. This shortens the syscall entry code, which no longer needs to clear syscall_noerror. The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow path to save the non-volatile GPRs into a signal frame. This removes the need for the assembly wrappers around sys_sigsuspend(), sys_rt_sigsuspend(), et al which existed solely to save those registers in advance. It also means I don't have to add new wrappers for ppoll() and pselect(), which is what I was supposed to be doing when I got distracted into this... Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit directly into a signal handler (as required by sigsuspend et al) by introducing a TIF_RESTOREALL flag which causes _all_ the registers to be reloaded from the pt_regs by taking the ret_from_exception path, instead of the normal syscall exit path which stomps on the callee-saved GPRs. It appears to pass an LTP test run on ppc64, and passes basic testing on ppc32 too. Brief tests of ptrace functionality with strace and gdb also appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-15 19:52:18 +01:00
li r11,-_LAST_ERRNO
powerpc: Fix various syscall/signal/swapcontext bugs A careful reading of the recent changes to the system call entry/exit paths revealed several problems, plus some things that could be simplified and improved: * 32-bit wasn't testing the _TIF_NOERROR bit in the syscall fast exit path, so it was only doing anything with it once it saw some other bit being set. In other words, the noerror behaviour would apply to the next system call where we had to reschedule or deliver a signal, which is not necessarily the current system call. * 32-bit wasn't doing the call to ptrace_notify in the syscall exit path when the _TIF_SINGLESTEP bit was set. * _TIF_RESTOREALL was in both _TIF_USER_WORK_MASK and _TIF_PERSYSCALL_MASK, which is odd since _TIF_RESTOREALL is only set by system calls. I took it out of _TIF_USER_WORK_MASK. * On 64-bit, _TIF_RESTOREALL wasn't causing the non-volatile registers to be restored (unless perhaps a signal was delivered or the syscall was traced or single-stepped). Thus the non-volatile registers weren't restored on exit from a signal handler. We probably got away with it mostly because signal handlers written in C wouldn't alter the non-volatile registers. * On 32-bit I simplified the code and made it more like 64-bit by making the syscall exit path jump to ret_from_except to handle preemption and signal delivery. * 32-bit was calling do_signal unnecessarily when _TIF_RESTOREALL was set - but I think because of that 32-bit was actually restoring the non-volatile registers on exit from a signal handler. * I changed the order of enabling interrupts and saving the non-volatile registers before calling do_syscall_trace_leave; now we enable interrupts first. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-08 03:24:22 +01:00
andi. r0,r9,(_TIF_SYSCALL_T_OR_A|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
bne- syscall_exit_work
[PATCH] syscall entry/exit revamp This cleanup patch speeds up the null syscall path on ppc64 by about 3%, and brings the ppc32 and ppc64 code slightly closer together. The ppc64 code was checking current_thread_info()->flags twice in the syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after disabling interrupts. Now we do the same as ppc32 -- check the flags only once in the fast path, and re-enable interrupts if necessary in the ptrace case. The patch abolishes the 'syscall_noerror' member of struct thread_info and replaces it with a TIF_NOERROR bit in the flags, which is handled in the slow path. This shortens the syscall entry code, which no longer needs to clear syscall_noerror. The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow path to save the non-volatile GPRs into a signal frame. This removes the need for the assembly wrappers around sys_sigsuspend(), sys_rt_sigsuspend(), et al which existed solely to save those registers in advance. It also means I don't have to add new wrappers for ppoll() and pselect(), which is what I was supposed to be doing when I got distracted into this... Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit directly into a signal handler (as required by sigsuspend et al) by introducing a TIF_RESTOREALL flag which causes _all_ the registers to be reloaded from the pt_regs by taking the ret_from_exception path, instead of the normal syscall exit path which stomps on the callee-saved GPRs. It appears to pass an LTP test run on ppc64, and passes basic testing on ppc32 too. Brief tests of ptrace functionality with strace and gdb also appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-15 19:52:18 +01:00
cmpld r3,r11
ld r5,_CCR(r1)
bge- syscall_error
powerpc: Hide some system call labels from profile tools syscall_dotrace_cont and syscall_error_cont tend to complicate perf output so make them local. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-04-04 20:23:27 +02:00
.Lsyscall_error_cont:
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
ld r7,_NIP(r1)
powerpc: Feature nop out reservation clear when stcx checks address The POWER architecture does not require stcx to check that it is operating on the same address as the larx. This means it is possible for an an exception handler to execute a larx, get a reservation, decide not to do the stcx and then return back with an active reservation. If the interrupted code was in the middle of a larx/stcx sequence the stcx could incorrectly succeed. All recent POWER CPUs check the address before letting the stcx succeed so we can create a CPU feature and nop it out. As Ben suggested, we can only do this in our syscall path because there is a remote possibility some kernel code gets interrupted by an exception that ends up operating on the same cacheline. Thanks to Paul Mackerras and Derek Williams for the idea. To test this I used a very simple null syscall (actually getppid) testcase at http://ozlabs.org/~anton/junkcode/null_syscall.c I tested against 2.6.35-git10 with the following changes against the pseries_defconfig: CONFIG_VIRT_CPU_ACCOUNTING=n CONFIG_AUDIT=n CONFIG_PPC_4K_PAGES=n CONFIG_PPC_64K_PAGES=y CONFIG_FORCE_MAX_ZONEORDER=9 CONFIG_PPC_SUBPAGE_PROT=n CONFIG_FUNCTION_TRACER=n CONFIG_FUNCTION_GRAPH_TRACER=n CONFIG_IRQSOFF_TRACER=n CONFIG_STACK_TRACER=n to remove the overhead of virtual CPU accounting, syscall auditing and the ftrace mcount tracers. 64kB pages were enabled to minimise TLB misses. POWER6: +8.2% POWER7: +7.0% Another suggestion was to use a larx to something in the L1 instead of a stcx. This was almost as fast as removing the larx on POWER6, but only 3.5% faster on POWER7. We can use this to speed up the reservation clear in our exception exit code. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-11 03:40:27 +02:00
BEGIN_FTR_SECTION
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
stdcx. r0,0,r1 /* to clear the reservation */
powerpc: Feature nop out reservation clear when stcx checks address The POWER architecture does not require stcx to check that it is operating on the same address as the larx. This means it is possible for an an exception handler to execute a larx, get a reservation, decide not to do the stcx and then return back with an active reservation. If the interrupted code was in the middle of a larx/stcx sequence the stcx could incorrectly succeed. All recent POWER CPUs check the address before letting the stcx succeed so we can create a CPU feature and nop it out. As Ben suggested, we can only do this in our syscall path because there is a remote possibility some kernel code gets interrupted by an exception that ends up operating on the same cacheline. Thanks to Paul Mackerras and Derek Williams for the idea. To test this I used a very simple null syscall (actually getppid) testcase at http://ozlabs.org/~anton/junkcode/null_syscall.c I tested against 2.6.35-git10 with the following changes against the pseries_defconfig: CONFIG_VIRT_CPU_ACCOUNTING=n CONFIG_AUDIT=n CONFIG_PPC_4K_PAGES=n CONFIG_PPC_64K_PAGES=y CONFIG_FORCE_MAX_ZONEORDER=9 CONFIG_PPC_SUBPAGE_PROT=n CONFIG_FUNCTION_TRACER=n CONFIG_FUNCTION_GRAPH_TRACER=n CONFIG_IRQSOFF_TRACER=n CONFIG_STACK_TRACER=n to remove the overhead of virtual CPU accounting, syscall auditing and the ftrace mcount tracers. 64kB pages were enabled to minimise TLB misses. POWER6: +8.2% POWER7: +7.0% Another suggestion was to use a larx to something in the L1 instead of a stcx. This was almost as fast as removing the larx on POWER6, but only 3.5% faster on POWER7. We can use this to speed up the reservation clear in our exception exit code. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-11 03:40:27 +02:00
END_FTR_SECTION_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
andi. r6,r8,MSR_PR
ld r4,_LINK(r1)
[POWERPC] Clear RI bit in MSR before restoring r13 when returning to userspace Some instruction tracing tools use the RI (recoverable interrupt) bit in the MSR to indicate when it's safe to single-step. Currently we clear RI after restoring r13 when returning to userspace. However, if we single-step past the point where r13 is restored, we'll corrupt r13 in the exception entry code and not restore it. This moves the clearing of RI to just before r13 is restored so this doesn't happen. Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-02-07 03:13:26 +01:00
/*
* Clear RI before restoring r13. If we are returning to
* userspace and we take an exception after restoring r13,
* we end up corrupting the userspace r13 value.
*/
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#ifdef CONFIG_PPC_BOOK3S
/* No MSR:RI on BookE */
[POWERPC] Clear RI bit in MSR before restoring r13 when returning to userspace Some instruction tracing tools use the RI (recoverable interrupt) bit in the MSR to indicate when it's safe to single-step. Currently we clear RI after restoring r13 when returning to userspace. However, if we single-step past the point where r13 is restored, we'll corrupt r13 in the exception entry code and not restore it. This moves the clearing of RI to just before r13 is restored so this doesn't happen. Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-02-07 03:13:26 +01:00
li r12,MSR_RI
andc r11,r10,r12
mtmsrd r11,1 /* clear MSR.RI */
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#endif /* CONFIG_PPC_BOOK3S */
powerpc: Implement accurate task and CPU time accounting This implements accurate task and cpu time accounting for 64-bit powerpc kernels. Instead of accounting a whole jiffy of time to a task on a timer interrupt because that task happened to be running at the time, we now account time in units of timebase ticks according to the actual time spent by the task in user mode and kernel mode. We also count the time spent processing hardware and software interrupts accurately. This is conditional on CONFIG_VIRT_CPU_ACCOUNTING. If that is not set, we do tick-based approximate accounting as before. To get this accurate information, we read either the PURR (processor utilization of resources register) on POWER5 machines, or the timebase on other machines on * each entry to the kernel from usermode * each exit to usermode * transitions between process context, hard irq context and soft irq context in kernel mode * context switches. On POWER5 systems with shared-processor logical partitioning we also read both the PURR and the timebase at each timer interrupt and context switch in order to determine how much time has been taken by the hypervisor to run other partitions ("steal" time). Unfortunately, since we need values of the PURR on both threads at the same time to accurately calculate the steal time, and since we can only calculate steal time on a per-core basis, the apportioning of the steal time between idle time (time which we ceded to the hypervisor in the idle loop) and actual stolen time is somewhat approximate at the moment. This is all based quite heavily on what s390 does, and it uses the generic interfaces that were added by the s390 developers, i.e. account_system_time(), account_user_time(), etc. This patch doesn't add any new interfaces between the kernel and userspace, and doesn't change the units in which time is reported to userspace by things such as /proc/stat, /proc/<pid>/stat, getrusage(), times(), etc. Internally the various task and cpu times are stored in timebase units, but they are converted to USER_HZ units (1/100th of a second) when reported to userspace. Some precision is therefore lost but there should not be any accumulating error, since the internal accumulation is at full precision. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-02-24 00:06:59 +01:00
beq- 1f
ACCOUNT_CPU_USER_EXIT(r11, r12)
ld r13,GPR13(r1) /* only restore r13 if returning to usermode */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
1: ld r2,GPR2(r1)
ld r1,GPR1(r1)
mtlr r4
mtcr r5
mtspr SPRN_SRR0,r7
mtspr SPRN_SRR1,r8
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
RFI
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
b . /* prevent speculative execution */
[PATCH] syscall entry/exit revamp This cleanup patch speeds up the null syscall path on ppc64 by about 3%, and brings the ppc32 and ppc64 code slightly closer together. The ppc64 code was checking current_thread_info()->flags twice in the syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after disabling interrupts. Now we do the same as ppc32 -- check the flags only once in the fast path, and re-enable interrupts if necessary in the ptrace case. The patch abolishes the 'syscall_noerror' member of struct thread_info and replaces it with a TIF_NOERROR bit in the flags, which is handled in the slow path. This shortens the syscall entry code, which no longer needs to clear syscall_noerror. The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow path to save the non-volatile GPRs into a signal frame. This removes the need for the assembly wrappers around sys_sigsuspend(), sys_rt_sigsuspend(), et al which existed solely to save those registers in advance. It also means I don't have to add new wrappers for ppoll() and pselect(), which is what I was supposed to be doing when I got distracted into this... Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit directly into a signal handler (as required by sigsuspend et al) by introducing a TIF_RESTOREALL flag which causes _all_ the registers to be reloaded from the pt_regs by taking the ret_from_exception path, instead of the normal syscall exit path which stomps on the callee-saved GPRs. It appears to pass an LTP test run on ppc64, and passes basic testing on ppc32 too. Brief tests of ptrace functionality with strace and gdb also appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-15 19:52:18 +01:00
syscall_error:
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
oris r5,r5,0x1000 /* Set SO bit in CR */
[PATCH] syscall entry/exit revamp This cleanup patch speeds up the null syscall path on ppc64 by about 3%, and brings the ppc32 and ppc64 code slightly closer together. The ppc64 code was checking current_thread_info()->flags twice in the syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after disabling interrupts. Now we do the same as ppc32 -- check the flags only once in the fast path, and re-enable interrupts if necessary in the ptrace case. The patch abolishes the 'syscall_noerror' member of struct thread_info and replaces it with a TIF_NOERROR bit in the flags, which is handled in the slow path. This shortens the syscall entry code, which no longer needs to clear syscall_noerror. The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow path to save the non-volatile GPRs into a signal frame. This removes the need for the assembly wrappers around sys_sigsuspend(), sys_rt_sigsuspend(), et al which existed solely to save those registers in advance. It also means I don't have to add new wrappers for ppoll() and pselect(), which is what I was supposed to be doing when I got distracted into this... Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit directly into a signal handler (as required by sigsuspend et al) by introducing a TIF_RESTOREALL flag which causes _all_ the registers to be reloaded from the pt_regs by taking the ret_from_exception path, instead of the normal syscall exit path which stomps on the callee-saved GPRs. It appears to pass an LTP test run on ppc64, and passes basic testing on ppc32 too. Brief tests of ptrace functionality with strace and gdb also appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-15 19:52:18 +01:00
neg r3,r3
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
std r5,_CCR(r1)
powerpc: Hide some system call labels from profile tools syscall_dotrace_cont and syscall_error_cont tend to complicate perf output so make them local. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-04-04 20:23:27 +02:00
b .Lsyscall_error_cont
[PATCH] syscall entry/exit revamp This cleanup patch speeds up the null syscall path on ppc64 by about 3%, and brings the ppc32 and ppc64 code slightly closer together. The ppc64 code was checking current_thread_info()->flags twice in the syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after disabling interrupts. Now we do the same as ppc32 -- check the flags only once in the fast path, and re-enable interrupts if necessary in the ptrace case. The patch abolishes the 'syscall_noerror' member of struct thread_info and replaces it with a TIF_NOERROR bit in the flags, which is handled in the slow path. This shortens the syscall entry code, which no longer needs to clear syscall_noerror. The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow path to save the non-volatile GPRs into a signal frame. This removes the need for the assembly wrappers around sys_sigsuspend(), sys_rt_sigsuspend(), et al which existed solely to save those registers in advance. It also means I don't have to add new wrappers for ppoll() and pselect(), which is what I was supposed to be doing when I got distracted into this... Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit directly into a signal handler (as required by sigsuspend et al) by introducing a TIF_RESTOREALL flag which causes _all_ the registers to be reloaded from the pt_regs by taking the ret_from_exception path, instead of the normal syscall exit path which stomps on the callee-saved GPRs. It appears to pass an LTP test run on ppc64, and passes basic testing on ppc32 too. Brief tests of ptrace functionality with strace and gdb also appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-15 19:52:18 +01:00
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
/* Traced system call support */
syscall_dotrace:
bl .save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
bl .do_syscall_trace_enter
powerpc: Make syscall tracing use tracehook.h helpers This changes powerpc syscall tracing to use the new tracehook.h entry points. There is no change, only cleanup. In addition, the assembly changes allow do_syscall_trace_enter() to abort the syscall without losing the information about the original r0 value. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-27 08:51:03 +02:00
/*
* Restore argument registers possibly just changed.
* We use the return value of do_syscall_trace_enter
* for the call number to look up in the table (r0).
*/
mr r0,r3
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
ld r3,GPR3(r1)
ld r4,GPR4(r1)
ld r5,GPR5(r1)
ld r6,GPR6(r1)
ld r7,GPR7(r1)
ld r8,GPR8(r1)
addi r9,r1,STACK_FRAME_OVERHEAD
clrrdi r10,r1,THREAD_SHIFT
ld r10,TI_FLAGS(r10)
powerpc: Hide some system call labels from profile tools syscall_dotrace_cont and syscall_error_cont tend to complicate perf output so make them local. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-04-04 20:23:27 +02:00
b .Lsyscall_dotrace_cont
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
[PATCH] syscall entry/exit revamp This cleanup patch speeds up the null syscall path on ppc64 by about 3%, and brings the ppc32 and ppc64 code slightly closer together. The ppc64 code was checking current_thread_info()->flags twice in the syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after disabling interrupts. Now we do the same as ppc32 -- check the flags only once in the fast path, and re-enable interrupts if necessary in the ptrace case. The patch abolishes the 'syscall_noerror' member of struct thread_info and replaces it with a TIF_NOERROR bit in the flags, which is handled in the slow path. This shortens the syscall entry code, which no longer needs to clear syscall_noerror. The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow path to save the non-volatile GPRs into a signal frame. This removes the need for the assembly wrappers around sys_sigsuspend(), sys_rt_sigsuspend(), et al which existed solely to save those registers in advance. It also means I don't have to add new wrappers for ppoll() and pselect(), which is what I was supposed to be doing when I got distracted into this... Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit directly into a signal handler (as required by sigsuspend et al) by introducing a TIF_RESTOREALL flag which causes _all_ the registers to be reloaded from the pt_regs by taking the ret_from_exception path, instead of the normal syscall exit path which stomps on the callee-saved GPRs. It appears to pass an LTP test run on ppc64, and passes basic testing on ppc32 too. Brief tests of ptrace functionality with strace and gdb also appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-15 19:52:18 +01:00
syscall_enosys:
li r3,-ENOSYS
b syscall_exit
syscall_exit_work:
/* If TIF_RESTOREALL is set, don't scribble on either r3 or ccr.
If TIF_NOERROR is set, just save r3 as it is. */
andi. r0,r9,_TIF_RESTOREALL
powerpc: Fix various syscall/signal/swapcontext bugs A careful reading of the recent changes to the system call entry/exit paths revealed several problems, plus some things that could be simplified and improved: * 32-bit wasn't testing the _TIF_NOERROR bit in the syscall fast exit path, so it was only doing anything with it once it saw some other bit being set. In other words, the noerror behaviour would apply to the next system call where we had to reschedule or deliver a signal, which is not necessarily the current system call. * 32-bit wasn't doing the call to ptrace_notify in the syscall exit path when the _TIF_SINGLESTEP bit was set. * _TIF_RESTOREALL was in both _TIF_USER_WORK_MASK and _TIF_PERSYSCALL_MASK, which is odd since _TIF_RESTOREALL is only set by system calls. I took it out of _TIF_USER_WORK_MASK. * On 64-bit, _TIF_RESTOREALL wasn't causing the non-volatile registers to be restored (unless perhaps a signal was delivered or the syscall was traced or single-stepped). Thus the non-volatile registers weren't restored on exit from a signal handler. We probably got away with it mostly because signal handlers written in C wouldn't alter the non-volatile registers. * On 32-bit I simplified the code and made it more like 64-bit by making the syscall exit path jump to ret_from_except to handle preemption and signal delivery. * 32-bit was calling do_signal unnecessarily when _TIF_RESTOREALL was set - but I think because of that 32-bit was actually restoring the non-volatile registers on exit from a signal handler. * I changed the order of enabling interrupts and saving the non-volatile registers before calling do_syscall_trace_leave; now we enable interrupts first. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-08 03:24:22 +01:00
beq+ 0f
REST_NVGPRS(r1)
b 2f
0: cmpld r3,r11 /* r10 is -LAST_ERRNO */
[PATCH] syscall entry/exit revamp This cleanup patch speeds up the null syscall path on ppc64 by about 3%, and brings the ppc32 and ppc64 code slightly closer together. The ppc64 code was checking current_thread_info()->flags twice in the syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after disabling interrupts. Now we do the same as ppc32 -- check the flags only once in the fast path, and re-enable interrupts if necessary in the ptrace case. The patch abolishes the 'syscall_noerror' member of struct thread_info and replaces it with a TIF_NOERROR bit in the flags, which is handled in the slow path. This shortens the syscall entry code, which no longer needs to clear syscall_noerror. The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow path to save the non-volatile GPRs into a signal frame. This removes the need for the assembly wrappers around sys_sigsuspend(), sys_rt_sigsuspend(), et al which existed solely to save those registers in advance. It also means I don't have to add new wrappers for ppoll() and pselect(), which is what I was supposed to be doing when I got distracted into this... Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit directly into a signal handler (as required by sigsuspend et al) by introducing a TIF_RESTOREALL flag which causes _all_ the registers to be reloaded from the pt_regs by taking the ret_from_exception path, instead of the normal syscall exit path which stomps on the callee-saved GPRs. It appears to pass an LTP test run on ppc64, and passes basic testing on ppc32 too. Brief tests of ptrace functionality with strace and gdb also appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-15 19:52:18 +01:00
blt+ 1f
andi. r0,r9,_TIF_NOERROR
bne- 1f
ld r5,_CCR(r1)
neg r3,r3
oris r5,r5,0x1000 /* Set SO bit in CR */
std r5,_CCR(r1)
1: std r3,GPR3(r1)
2: andi. r0,r9,(_TIF_PERSYSCALL_MASK)
beq 4f
powerpc: Fix various syscall/signal/swapcontext bugs A careful reading of the recent changes to the system call entry/exit paths revealed several problems, plus some things that could be simplified and improved: * 32-bit wasn't testing the _TIF_NOERROR bit in the syscall fast exit path, so it was only doing anything with it once it saw some other bit being set. In other words, the noerror behaviour would apply to the next system call where we had to reschedule or deliver a signal, which is not necessarily the current system call. * 32-bit wasn't doing the call to ptrace_notify in the syscall exit path when the _TIF_SINGLESTEP bit was set. * _TIF_RESTOREALL was in both _TIF_USER_WORK_MASK and _TIF_PERSYSCALL_MASK, which is odd since _TIF_RESTOREALL is only set by system calls. I took it out of _TIF_USER_WORK_MASK. * On 64-bit, _TIF_RESTOREALL wasn't causing the non-volatile registers to be restored (unless perhaps a signal was delivered or the syscall was traced or single-stepped). Thus the non-volatile registers weren't restored on exit from a signal handler. We probably got away with it mostly because signal handlers written in C wouldn't alter the non-volatile registers. * On 32-bit I simplified the code and made it more like 64-bit by making the syscall exit path jump to ret_from_except to handle preemption and signal delivery. * 32-bit was calling do_signal unnecessarily when _TIF_RESTOREALL was set - but I think because of that 32-bit was actually restoring the non-volatile registers on exit from a signal handler. * I changed the order of enabling interrupts and saving the non-volatile registers before calling do_syscall_trace_leave; now we enable interrupts first. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-08 03:24:22 +01:00
/* Clear per-syscall TIF flags if any are set. */
[PATCH] syscall entry/exit revamp This cleanup patch speeds up the null syscall path on ppc64 by about 3%, and brings the ppc32 and ppc64 code slightly closer together. The ppc64 code was checking current_thread_info()->flags twice in the syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after disabling interrupts. Now we do the same as ppc32 -- check the flags only once in the fast path, and re-enable interrupts if necessary in the ptrace case. The patch abolishes the 'syscall_noerror' member of struct thread_info and replaces it with a TIF_NOERROR bit in the flags, which is handled in the slow path. This shortens the syscall entry code, which no longer needs to clear syscall_noerror. The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow path to save the non-volatile GPRs into a signal frame. This removes the need for the assembly wrappers around sys_sigsuspend(), sys_rt_sigsuspend(), et al which existed solely to save those registers in advance. It also means I don't have to add new wrappers for ppoll() and pselect(), which is what I was supposed to be doing when I got distracted into this... Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit directly into a signal handler (as required by sigsuspend et al) by introducing a TIF_RESTOREALL flag which causes _all_ the registers to be reloaded from the pt_regs by taking the ret_from_exception path, instead of the normal syscall exit path which stomps on the callee-saved GPRs. It appears to pass an LTP test run on ppc64, and passes basic testing on ppc32 too. Brief tests of ptrace functionality with strace and gdb also appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-15 19:52:18 +01:00
li r11,_TIF_PERSYSCALL_MASK
addi r12,r12,TI_FLAGS
3: ldarx r10,0,r12
andc r10,r10,r11
stdcx. r10,0,r12
bne- 3b
subi r12,r12,TI_FLAGS
powerpc: Fix various syscall/signal/swapcontext bugs A careful reading of the recent changes to the system call entry/exit paths revealed several problems, plus some things that could be simplified and improved: * 32-bit wasn't testing the _TIF_NOERROR bit in the syscall fast exit path, so it was only doing anything with it once it saw some other bit being set. In other words, the noerror behaviour would apply to the next system call where we had to reschedule or deliver a signal, which is not necessarily the current system call. * 32-bit wasn't doing the call to ptrace_notify in the syscall exit path when the _TIF_SINGLESTEP bit was set. * _TIF_RESTOREALL was in both _TIF_USER_WORK_MASK and _TIF_PERSYSCALL_MASK, which is odd since _TIF_RESTOREALL is only set by system calls. I took it out of _TIF_USER_WORK_MASK. * On 64-bit, _TIF_RESTOREALL wasn't causing the non-volatile registers to be restored (unless perhaps a signal was delivered or the syscall was traced or single-stepped). Thus the non-volatile registers weren't restored on exit from a signal handler. We probably got away with it mostly because signal handlers written in C wouldn't alter the non-volatile registers. * On 32-bit I simplified the code and made it more like 64-bit by making the syscall exit path jump to ret_from_except to handle preemption and signal delivery. * 32-bit was calling do_signal unnecessarily when _TIF_RESTOREALL was set - but I think because of that 32-bit was actually restoring the non-volatile registers on exit from a signal handler. * I changed the order of enabling interrupts and saving the non-volatile registers before calling do_syscall_trace_leave; now we enable interrupts first. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-08 03:24:22 +01:00
4: /* Anything else left to do? */
andi. r0,r9,(_TIF_SYSCALL_T_OR_A|_TIF_SINGLESTEP)
[PATCH] syscall entry/exit revamp This cleanup patch speeds up the null syscall path on ppc64 by about 3%, and brings the ppc32 and ppc64 code slightly closer together. The ppc64 code was checking current_thread_info()->flags twice in the syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after disabling interrupts. Now we do the same as ppc32 -- check the flags only once in the fast path, and re-enable interrupts if necessary in the ptrace case. The patch abolishes the 'syscall_noerror' member of struct thread_info and replaces it with a TIF_NOERROR bit in the flags, which is handled in the slow path. This shortens the syscall entry code, which no longer needs to clear syscall_noerror. The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow path to save the non-volatile GPRs into a signal frame. This removes the need for the assembly wrappers around sys_sigsuspend(), sys_rt_sigsuspend(), et al which existed solely to save those registers in advance. It also means I don't have to add new wrappers for ppoll() and pselect(), which is what I was supposed to be doing when I got distracted into this... Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit directly into a signal handler (as required by sigsuspend et al) by introducing a TIF_RESTOREALL flag which causes _all_ the registers to be reloaded from the pt_regs by taking the ret_from_exception path, instead of the normal syscall exit path which stomps on the callee-saved GPRs. It appears to pass an LTP test run on ppc64, and passes basic testing on ppc32 too. Brief tests of ptrace functionality with strace and gdb also appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-15 19:52:18 +01:00
beq .ret_from_except_lite
/* Re-enable interrupts */
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#ifdef CONFIG_PPC_BOOK3E
wrteei 1
#else
powerpc: Improve 64-bit syscall entry/exit We unconditionally hard enable interrupts. This is unnecessary as syscalls are expected to always be called with interrupts enabled. While at it, we add a WARN_ON if that is not the case and CONFIG_TRACE_IRQFLAGS is enabled (we don't want to add overhead to the fast path when this is not set though). Thus let's remove the enabling (and associated irq tracing) from the syscall entry path. Also on Book3S, replace a few mfmsr instructions with loads of PACAMSR from the PACA, which should be faster & schedule better. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-01 05:40:23 +01:00
ld r10,PACAKMSR(r13)
[PATCH] syscall entry/exit revamp This cleanup patch speeds up the null syscall path on ppc64 by about 3%, and brings the ppc32 and ppc64 code slightly closer together. The ppc64 code was checking current_thread_info()->flags twice in the syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after disabling interrupts. Now we do the same as ppc32 -- check the flags only once in the fast path, and re-enable interrupts if necessary in the ptrace case. The patch abolishes the 'syscall_noerror' member of struct thread_info and replaces it with a TIF_NOERROR bit in the flags, which is handled in the slow path. This shortens the syscall entry code, which no longer needs to clear syscall_noerror. The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow path to save the non-volatile GPRs into a signal frame. This removes the need for the assembly wrappers around sys_sigsuspend(), sys_rt_sigsuspend(), et al which existed solely to save those registers in advance. It also means I don't have to add new wrappers for ppoll() and pselect(), which is what I was supposed to be doing when I got distracted into this... Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit directly into a signal handler (as required by sigsuspend et al) by introducing a TIF_RESTOREALL flag which causes _all_ the registers to be reloaded from the pt_regs by taking the ret_from_exception path, instead of the normal syscall exit path which stomps on the callee-saved GPRs. It appears to pass an LTP test run on ppc64, and passes basic testing on ppc32 too. Brief tests of ptrace functionality with strace and gdb also appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-15 19:52:18 +01:00
ori r10,r10,MSR_EE
mtmsrd r10,1
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#endif /* CONFIG_PPC_BOOK3E */
[PATCH] syscall entry/exit revamp This cleanup patch speeds up the null syscall path on ppc64 by about 3%, and brings the ppc32 and ppc64 code slightly closer together. The ppc64 code was checking current_thread_info()->flags twice in the syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after disabling interrupts. Now we do the same as ppc32 -- check the flags only once in the fast path, and re-enable interrupts if necessary in the ptrace case. The patch abolishes the 'syscall_noerror' member of struct thread_info and replaces it with a TIF_NOERROR bit in the flags, which is handled in the slow path. This shortens the syscall entry code, which no longer needs to clear syscall_noerror. The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow path to save the non-volatile GPRs into a signal frame. This removes the need for the assembly wrappers around sys_sigsuspend(), sys_rt_sigsuspend(), et al which existed solely to save those registers in advance. It also means I don't have to add new wrappers for ppoll() and pselect(), which is what I was supposed to be doing when I got distracted into this... Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit directly into a signal handler (as required by sigsuspend et al) by introducing a TIF_RESTOREALL flag which causes _all_ the registers to be reloaded from the pt_regs by taking the ret_from_exception path, instead of the normal syscall exit path which stomps on the callee-saved GPRs. It appears to pass an LTP test run on ppc64, and passes basic testing on ppc32 too. Brief tests of ptrace functionality with strace and gdb also appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-15 19:52:18 +01:00
powerpc: Fix various syscall/signal/swapcontext bugs A careful reading of the recent changes to the system call entry/exit paths revealed several problems, plus some things that could be simplified and improved: * 32-bit wasn't testing the _TIF_NOERROR bit in the syscall fast exit path, so it was only doing anything with it once it saw some other bit being set. In other words, the noerror behaviour would apply to the next system call where we had to reschedule or deliver a signal, which is not necessarily the current system call. * 32-bit wasn't doing the call to ptrace_notify in the syscall exit path when the _TIF_SINGLESTEP bit was set. * _TIF_RESTOREALL was in both _TIF_USER_WORK_MASK and _TIF_PERSYSCALL_MASK, which is odd since _TIF_RESTOREALL is only set by system calls. I took it out of _TIF_USER_WORK_MASK. * On 64-bit, _TIF_RESTOREALL wasn't causing the non-volatile registers to be restored (unless perhaps a signal was delivered or the syscall was traced or single-stepped). Thus the non-volatile registers weren't restored on exit from a signal handler. We probably got away with it mostly because signal handlers written in C wouldn't alter the non-volatile registers. * On 32-bit I simplified the code and made it more like 64-bit by making the syscall exit path jump to ret_from_except to handle preemption and signal delivery. * 32-bit was calling do_signal unnecessarily when _TIF_RESTOREALL was set - but I think because of that 32-bit was actually restoring the non-volatile registers on exit from a signal handler. * I changed the order of enabling interrupts and saving the non-volatile registers before calling do_syscall_trace_leave; now we enable interrupts first. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-08 03:24:22 +01:00
bl .save_nvgprs
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
addi r3,r1,STACK_FRAME_OVERHEAD
bl .do_syscall_trace_leave
powerpc: Fix various syscall/signal/swapcontext bugs A careful reading of the recent changes to the system call entry/exit paths revealed several problems, plus some things that could be simplified and improved: * 32-bit wasn't testing the _TIF_NOERROR bit in the syscall fast exit path, so it was only doing anything with it once it saw some other bit being set. In other words, the noerror behaviour would apply to the next system call where we had to reschedule or deliver a signal, which is not necessarily the current system call. * 32-bit wasn't doing the call to ptrace_notify in the syscall exit path when the _TIF_SINGLESTEP bit was set. * _TIF_RESTOREALL was in both _TIF_USER_WORK_MASK and _TIF_PERSYSCALL_MASK, which is odd since _TIF_RESTOREALL is only set by system calls. I took it out of _TIF_USER_WORK_MASK. * On 64-bit, _TIF_RESTOREALL wasn't causing the non-volatile registers to be restored (unless perhaps a signal was delivered or the syscall was traced or single-stepped). Thus the non-volatile registers weren't restored on exit from a signal handler. We probably got away with it mostly because signal handlers written in C wouldn't alter the non-volatile registers. * On 32-bit I simplified the code and made it more like 64-bit by making the syscall exit path jump to ret_from_except to handle preemption and signal delivery. * 32-bit was calling do_signal unnecessarily when _TIF_RESTOREALL was set - but I think because of that 32-bit was actually restoring the non-volatile registers on exit from a signal handler. * I changed the order of enabling interrupts and saving the non-volatile registers before calling do_syscall_trace_leave; now we enable interrupts first. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-08 03:24:22 +01:00
b .ret_from_except
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
/* Save non-volatile GPRs, if not already saved. */
_GLOBAL(save_nvgprs)
ld r11,_TRAP(r1)
andi. r0,r11,1
beqlr-
SAVE_NVGPRS(r1)
clrrdi r0,r11,1
std r0,_TRAP(r1)
blr
[PATCH] syscall entry/exit revamp This cleanup patch speeds up the null syscall path on ppc64 by about 3%, and brings the ppc32 and ppc64 code slightly closer together. The ppc64 code was checking current_thread_info()->flags twice in the syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after disabling interrupts. Now we do the same as ppc32 -- check the flags only once in the fast path, and re-enable interrupts if necessary in the ptrace case. The patch abolishes the 'syscall_noerror' member of struct thread_info and replaces it with a TIF_NOERROR bit in the flags, which is handled in the slow path. This shortens the syscall entry code, which no longer needs to clear syscall_noerror. The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow path to save the non-volatile GPRs into a signal frame. This removes the need for the assembly wrappers around sys_sigsuspend(), sys_rt_sigsuspend(), et al which existed solely to save those registers in advance. It also means I don't have to add new wrappers for ppoll() and pselect(), which is what I was supposed to be doing when I got distracted into this... Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit directly into a signal handler (as required by sigsuspend et al) by introducing a TIF_RESTOREALL flag which causes _all_ the registers to be reloaded from the pt_regs by taking the ret_from_exception path, instead of the normal syscall exit path which stomps on the callee-saved GPRs. It appears to pass an LTP test run on ppc64, and passes basic testing on ppc32 too. Brief tests of ptrace functionality with strace and gdb also appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :) Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-15 19:52:18 +01:00
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
/*
* The sigsuspend and rt_sigsuspend system calls can call do_signal
* and thus put the process into the stopped state where we might
* want to examine its user state with ptrace. Therefore we need
* to save all the nonvolatile registers (r14 - r31) before calling
* the C code. Similarly, fork, vfork and clone need the full
* register state on the stack so that it can be copied to the child.
*/
_GLOBAL(ppc_fork)
bl .save_nvgprs
bl .sys_fork
b syscall_exit
_GLOBAL(ppc_vfork)
bl .save_nvgprs
bl .sys_vfork
b syscall_exit
_GLOBAL(ppc_clone)
bl .save_nvgprs
bl .sys_clone
b syscall_exit
powerpc: Fix various syscall/signal/swapcontext bugs A careful reading of the recent changes to the system call entry/exit paths revealed several problems, plus some things that could be simplified and improved: * 32-bit wasn't testing the _TIF_NOERROR bit in the syscall fast exit path, so it was only doing anything with it once it saw some other bit being set. In other words, the noerror behaviour would apply to the next system call where we had to reschedule or deliver a signal, which is not necessarily the current system call. * 32-bit wasn't doing the call to ptrace_notify in the syscall exit path when the _TIF_SINGLESTEP bit was set. * _TIF_RESTOREALL was in both _TIF_USER_WORK_MASK and _TIF_PERSYSCALL_MASK, which is odd since _TIF_RESTOREALL is only set by system calls. I took it out of _TIF_USER_WORK_MASK. * On 64-bit, _TIF_RESTOREALL wasn't causing the non-volatile registers to be restored (unless perhaps a signal was delivered or the syscall was traced or single-stepped). Thus the non-volatile registers weren't restored on exit from a signal handler. We probably got away with it mostly because signal handlers written in C wouldn't alter the non-volatile registers. * On 32-bit I simplified the code and made it more like 64-bit by making the syscall exit path jump to ret_from_except to handle preemption and signal delivery. * 32-bit was calling do_signal unnecessarily when _TIF_RESTOREALL was set - but I think because of that 32-bit was actually restoring the non-volatile registers on exit from a signal handler. * I changed the order of enabling interrupts and saving the non-volatile registers before calling do_syscall_trace_leave; now we enable interrupts first. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-08 03:24:22 +01:00
_GLOBAL(ppc32_swapcontext)
bl .save_nvgprs
bl .compat_sys_swapcontext
b syscall_exit
_GLOBAL(ppc64_swapcontext)
bl .save_nvgprs
bl .sys_swapcontext
b syscall_exit
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
_GLOBAL(ret_from_fork)
bl .schedule_tail
REST_NVGPRS(r1)
li r3,0
b syscall_exit
/*
* This routine switches between two different tasks. The process
* state of one is saved on its kernel stack. Then the state
* of the other is restored from its kernel stack. The memory
* management hardware is updated to the second process's state.
* Finally, we can return to the second process, via ret_from_except.
* On entry, r3 points to the THREAD for the current task, r4
* points to the THREAD for the new task.
*
* Note: there are two ways to get to the "going out" portion
* of this code; either by coming in via the entry (_switch)
* or via "fork" which must set up an environment equivalent
* to the "_switch" path. If you change this you'll have to change
* the fork code also.
*
* The code which creates the new task context is in 'copy_thread'
[PATCH] powerpc: trivial: modify comments to refer to new location of files This patch removes all self references and fixes references to files in the now defunct arch/ppc64 tree. I think this accomplises everything wanted, though there might be a few references I missed. Signed-off-by: Jon Mason <jdmason@us.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-01-23 17:58:20 +01:00
* in arch/powerpc/kernel/process.c
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
*/
.align 7
_GLOBAL(_switch)
mflr r0
std r0,16(r1)
stdu r1,-SWITCH_FRAME_SIZE(r1)
/* r3-r13 are caller saved -- Cort */
SAVE_8GPRS(14, r1)
SAVE_10GPRS(22, r1)
mflr r20 /* Return to switch caller */
mfmsr r22
li r0, MSR_FP
powerpc: Add VSX context save/restore, ptrace and signal support This patch extends the floating point save and restore code to use the VSX load/stores when VSX is available. This will make FP context save/restore marginally slower on FP only code, when VSX is available, as it has to load/store 128bits rather than just 64bits. Mixing FP, VMX and VSX code will get constant architected state. The signals interface is extended to enable access to VSR 0-31 doubleword 1 after discussions with tool chain maintainers. Backward compatibility is maintained. The ptrace interface is also extended to allow access to VSR 0-31 full registers. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-06-25 06:07:18 +02:00
#ifdef CONFIG_VSX
BEGIN_FTR_SECTION
oris r0,r0,MSR_VSX@h /* Disable VSX */
END_FTR_SECTION_IFSET(CPU_FTR_VSX)
#endif /* CONFIG_VSX */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
#ifdef CONFIG_ALTIVEC
BEGIN_FTR_SECTION
oris r0,r0,MSR_VEC@h /* Disable altivec */
mfspr r24,SPRN_VRSAVE /* save vrsave register value */
std r24,THREAD_VRSAVE(r3)
END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
#endif /* CONFIG_ALTIVEC */
powerpc: Per process DSCR + some fixes (try#4) The DSCR (aka Data Stream Control Register) is supported on some server PowerPC chips and allow some control over the prefetch of data streams. This patch allows the value to be specified per thread by emulating the corresponding mfspr and mtspr instructions. Children of such threads inherit the value. Other threads use a default value that can be specified in sysfs - /sys/devices/system/cpu/dscr_default. If a thread starts with non default value in the sysfs entry, all children threads inherit this non default value even if the sysfs value is changed later. Signed-off-by: Alexey Kardashevskiy <aik@au1.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-03-02 16:18:48 +01:00
#ifdef CONFIG_PPC64
BEGIN_FTR_SECTION
mfspr r25,SPRN_DSCR
std r25,THREAD_DSCR(r3)
END_FTR_SECTION_IFSET(CPU_FTR_DSCR)
#endif
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
and. r0,r0,r22
beq+ 1f
andc r22,r22,r0
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
MTMSRD(r22)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
isync
1: std r20,_NIP(r1)
mfcr r23
std r23,_CCR(r1)
std r1,KSP(r3) /* Set old stack pointer */
#ifdef CONFIG_SMP
/* We need a sync somewhere here to make sure that if the
* previous task gets rescheduled on another CPU, it sees all
* stores it has performed on this one.
*/
sync
#endif /* CONFIG_SMP */
powerpc: Feature nop out reservation clear when stcx checks address The POWER architecture does not require stcx to check that it is operating on the same address as the larx. This means it is possible for an an exception handler to execute a larx, get a reservation, decide not to do the stcx and then return back with an active reservation. If the interrupted code was in the middle of a larx/stcx sequence the stcx could incorrectly succeed. All recent POWER CPUs check the address before letting the stcx succeed so we can create a CPU feature and nop it out. As Ben suggested, we can only do this in our syscall path because there is a remote possibility some kernel code gets interrupted by an exception that ends up operating on the same cacheline. Thanks to Paul Mackerras and Derek Williams for the idea. To test this I used a very simple null syscall (actually getppid) testcase at http://ozlabs.org/~anton/junkcode/null_syscall.c I tested against 2.6.35-git10 with the following changes against the pseries_defconfig: CONFIG_VIRT_CPU_ACCOUNTING=n CONFIG_AUDIT=n CONFIG_PPC_4K_PAGES=n CONFIG_PPC_64K_PAGES=y CONFIG_FORCE_MAX_ZONEORDER=9 CONFIG_PPC_SUBPAGE_PROT=n CONFIG_FUNCTION_TRACER=n CONFIG_FUNCTION_GRAPH_TRACER=n CONFIG_IRQSOFF_TRACER=n CONFIG_STACK_TRACER=n to remove the overhead of virtual CPU accounting, syscall auditing and the ftrace mcount tracers. 64kB pages were enabled to minimise TLB misses. POWER6: +8.2% POWER7: +7.0% Another suggestion was to use a larx to something in the L1 instead of a stcx. This was almost as fast as removing the larx on POWER6, but only 3.5% faster on POWER7. We can use this to speed up the reservation clear in our exception exit code. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-11 03:40:27 +02:00
/*
* If we optimise away the clear of the reservation in system
* calls because we know the CPU tracks the address of the
* reservation, then we need to clear it here to cover the
* case that the kernel context switch path has no larx
* instructions.
*/
BEGIN_FTR_SECTION
ldarx r6,0,r1
END_FTR_SECTION_IFSET(CPU_FTR_STCX_CHECKS_ADDRESS)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
addi r6,r4,-THREAD /* Convert THREAD to 'current' */
std r6,PACACURRENT(r13) /* Set new 'current' */
ld r8,KSP(r4) /* new stack pointer */
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#ifdef CONFIG_PPC_BOOK3S
[POWERPC] Use 1TB segments This makes the kernel use 1TB segments for all kernel mappings and for user addresses of 1TB and above, on machines which support them (currently POWER5+, POWER6 and PA6T). We detect that the machine supports 1TB segments by looking at the ibm,processor-segment-sizes property in the device tree. We don't currently use 1TB segments for user addresses < 1T, since that would effectively prevent 32-bit processes from using huge pages unless we also had a way to revert to using 256MB segments. That would be possible but would involve extra complications (such as keeping track of which segment size was used when HPTEs were inserted) and is not addressed here. Parts of this patch were originally written by Ben Herrenschmidt. Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-10-11 12:37:10 +02:00
BEGIN_FTR_SECTION
powerpc: Use an alternative feature section in entry_64.S Use an alternative feature section in _switch. There are three cases handled here, either we don't have an SLB, in which case we jump over the entire code section, or if we do we either do or don't have 1TB segments. Boot tested on Power3, Power5 and Power5+. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-06-24 03:33:05 +02:00
BEGIN_FTR_SECTION_NESTED(95)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
clrrdi r6,r8,28 /* get its ESID */
clrrdi r9,r1,28 /* get current sp ESID */
powerpc: Use an alternative feature section in entry_64.S Use an alternative feature section in _switch. There are three cases handled here, either we don't have an SLB, in which case we jump over the entire code section, or if we do we either do or don't have 1TB segments. Boot tested on Power3, Power5 and Power5+. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-06-24 03:33:05 +02:00
FTR_SECTION_ELSE_NESTED(95)
[POWERPC] Use 1TB segments This makes the kernel use 1TB segments for all kernel mappings and for user addresses of 1TB and above, on machines which support them (currently POWER5+, POWER6 and PA6T). We detect that the machine supports 1TB segments by looking at the ibm,processor-segment-sizes property in the device tree. We don't currently use 1TB segments for user addresses < 1T, since that would effectively prevent 32-bit processes from using huge pages unless we also had a way to revert to using 256MB segments. That would be possible but would involve extra complications (such as keeping track of which segment size was used when HPTEs were inserted) and is not addressed here. Parts of this patch were originally written by Ben Herrenschmidt. Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-10-11 12:37:10 +02:00
clrrdi r6,r8,40 /* get its 1T ESID */
clrrdi r9,r1,40 /* get current sp 1T ESID */
powerpc: Free up some CPU feature bits by moving out MMU-related features Some of the 64bit PPC CPU features are MMU-related, so this patch moves them to MMU_FTR_ bits. All cpu_has_feature()-style tests are moved to mmu_has_feature(), and seven feature bits are freed as a result. Signed-off-by: Matt Evans <matt@ozlabs.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-04-06 21:48:50 +02:00
ALT_MMU_FTR_SECTION_END_NESTED_IFCLR(MMU_FTR_1T_SEGMENT, 95)
powerpc: Use an alternative feature section in entry_64.S Use an alternative feature section in _switch. There are three cases handled here, either we don't have an SLB, in which case we jump over the entire code section, or if we do we either do or don't have 1TB segments. Boot tested on Power3, Power5 and Power5+. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-06-24 03:33:05 +02:00
FTR_SECTION_ELSE
b 2f
powerpc: Free up some CPU feature bits by moving out MMU-related features Some of the 64bit PPC CPU features are MMU-related, so this patch moves them to MMU_FTR_ bits. All cpu_has_feature()-style tests are moved to mmu_has_feature(), and seven feature bits are freed as a result. Signed-off-by: Matt Evans <matt@ozlabs.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-04-06 21:48:50 +02:00
ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_SLB)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
clrldi. r0,r6,2 /* is new ESID c00000000? */
cmpd cr1,r6,r9 /* or is new ESID the same as current ESID? */
cror eq,4*cr1+eq,eq
beq 2f /* if yes, don't slbie it */
/* Bolt in the new stack SLB entry */
ld r7,KSP_VSID(r4) /* Get new stack's VSID */
oris r0,r6,(SLB_ESID_V)@h
ori r0,r0,(SLB_NUM_BOLTED-1)@l
[POWERPC] Use 1TB segments This makes the kernel use 1TB segments for all kernel mappings and for user addresses of 1TB and above, on machines which support them (currently POWER5+, POWER6 and PA6T). We detect that the machine supports 1TB segments by looking at the ibm,processor-segment-sizes property in the device tree. We don't currently use 1TB segments for user addresses < 1T, since that would effectively prevent 32-bit processes from using huge pages unless we also had a way to revert to using 256MB segments. That would be possible but would involve extra complications (such as keeping track of which segment size was used when HPTEs were inserted) and is not addressed here. Parts of this patch were originally written by Ben Herrenschmidt. Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-10-11 12:37:10 +02:00
BEGIN_FTR_SECTION
li r9,MMU_SEGSIZE_1T /* insert B field */
oris r6,r6,(MMU_SEGSIZE_1T << SLBIE_SSIZE_SHIFT)@h
rldimi r7,r9,SLB_VSID_SSIZE_SHIFT,0
powerpc: Free up some CPU feature bits by moving out MMU-related features Some of the 64bit PPC CPU features are MMU-related, so this patch moves them to MMU_FTR_ bits. All cpu_has_feature()-style tests are moved to mmu_has_feature(), and seven feature bits are freed as a result. Signed-off-by: Matt Evans <matt@ozlabs.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-04-06 21:48:50 +02:00
END_MMU_FTR_SECTION_IFSET(MMU_FTR_1T_SEGMENT)
[POWERPC] Implement SLB shadow buffer This adds a shadow buffer for the SLBs and regsiters it with PHYP. Only the bolted SLB entries (top 3) are shadowed. The SLB shadow buffer tells the hypervisor what the kernel needs to have in the SLB for the kernel to be able to function. The hypervisor can use this information to speed up partition context switches. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-08-07 08:19:19 +02:00
[POWERPC] Remove barriers from the SLB shadow buffer update After talking to an IBM POWER hypervisor (PHYP) design and development guy, there seems to be no need for memory barriers when updating the SLB shadow buffer provided we only update it from the current CPU, which we do. Also, these guys see no need in the future for these barriers. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-08-24 08:58:37 +02:00
/* Update the last bolted SLB. No write barriers are needed
* here, provided we only update the current CPU's SLB shadow
* buffer.
*/
[POWERPC] Implement SLB shadow buffer This adds a shadow buffer for the SLBs and regsiters it with PHYP. Only the bolted SLB entries (top 3) are shadowed. The SLB shadow buffer tells the hypervisor what the kernel needs to have in the SLB for the kernel to be able to function. The hypervisor can use this information to speed up partition context switches. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-08-07 08:19:19 +02:00
ld r9,PACA_SLBSHADOWPTR(r13)
[POWERPC] SLB shadow buffer cleanup Cleanup some of the #define magic as suggested by Milton. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-08-09 09:00:30 +02:00
li r12,0
std r12,SLBSHADOW_STACKESID(r9) /* Clear ESID */
std r7,SLBSHADOW_STACKVSID(r9) /* Save VSID */
std r0,SLBSHADOW_STACKESID(r9) /* Save ESID */
[POWERPC] Implement SLB shadow buffer This adds a shadow buffer for the SLBs and regsiters it with PHYP. Only the bolted SLB entries (top 3) are shadowed. The SLB shadow buffer tells the hypervisor what the kernel needs to have in the SLB for the kernel to be able to function. The hypervisor can use this information to speed up partition context switches. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-08-07 08:19:19 +02:00
powerpc: Free up some CPU feature bits by moving out MMU-related features Some of the 64bit PPC CPU features are MMU-related, so this patch moves them to MMU_FTR_ bits. All cpu_has_feature()-style tests are moved to mmu_has_feature(), and seven feature bits are freed as a result. Signed-off-by: Matt Evans <matt@ozlabs.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-04-06 21:48:50 +02:00
/* No need to check for MMU_FTR_NO_SLBIE_B here, since when
[POWERPC] Add 1TB workaround for PA6T PA6T has a bug where the slbie instruction does not honor the large segment bit. As a result, we have to always use slbia when switching context. We don't have to worry about changing the slbie's during fault processing, since they should never be replacing one VSID with another using the same ESID. I.e. there's no risk for inserting duplicate entries due to a failed slbie of the old entry. So as long as we clear it out on context switch we should be fine. Signed-off-by: Olof Johansson <olof@lixom.net> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-10-15 16:58:59 +02:00
* we have 1TB segments, the only CPUs known to have the errata
* only support less than 1TB of system memory and we'll never
* actually hit this code path.
*/
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
slbie r6
slbie r6 /* Workaround POWER5 < DD2.1 issue */
slbmte r7,r0
isync
2:
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#endif /* !CONFIG_PPC_BOOK3S */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
clrrdi r7,r8,THREAD_SHIFT /* base of new stack */
/* Note: this uses SWITCH_FRAME_SIZE rather than INT_FRAME_SIZE
because we don't need to leave the 288-byte ABI gap at the
top of the kernel stack. */
addi r7,r7,THREAD_SIZE-SWITCH_FRAME_SIZE
mr r1,r8 /* start using new stack pointer */
std r7,PACAKSAVE(r13)
ld r6,_CCR(r1)
mtcrf 0xFF,r6
#ifdef CONFIG_ALTIVEC
BEGIN_FTR_SECTION
ld r0,THREAD_VRSAVE(r4)
mtspr SPRN_VRSAVE,r0 /* if G4, restore VRSAVE reg */
END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
#endif /* CONFIG_ALTIVEC */
powerpc: Per process DSCR + some fixes (try#4) The DSCR (aka Data Stream Control Register) is supported on some server PowerPC chips and allow some control over the prefetch of data streams. This patch allows the value to be specified per thread by emulating the corresponding mfspr and mtspr instructions. Children of such threads inherit the value. Other threads use a default value that can be specified in sysfs - /sys/devices/system/cpu/dscr_default. If a thread starts with non default value in the sysfs entry, all children threads inherit this non default value even if the sysfs value is changed later. Signed-off-by: Alexey Kardashevskiy <aik@au1.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-03-02 16:18:48 +01:00
#ifdef CONFIG_PPC64
BEGIN_FTR_SECTION
ld r0,THREAD_DSCR(r4)
cmpd r0,r25
beq 1f
mtspr SPRN_DSCR,r0
1:
END_FTR_SECTION_IFSET(CPU_FTR_DSCR)
#endif
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
/* r3-r13 are destroyed -- Cort */
REST_8GPRS(14, r1)
REST_10GPRS(22, r1)
/* convert old thread to its task_struct for return value */
addi r3,r3,-THREAD
ld r7,_NIP(r1) /* Return to _switch caller in new task */
mtlr r7
addi r1,r1,SWITCH_FRAME_SIZE
blr
.align 7
_GLOBAL(ret_from_except)
ld r11,_TRAP(r1)
andi. r0,r11,1
bne .ret_from_except_lite
REST_NVGPRS(r1)
_GLOBAL(ret_from_except_lite)
/*
* Disable interrupts so that current_thread_info()->flags
* can't change between when we test it and when we return
* from the interrupt.
*/
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#ifdef CONFIG_PPC_BOOK3E
wrteei 0
#else
powerpc: Replace mfmsr instructions with load from PACA kernel_msr field On 64-bit, the mfmsr instruction can be quite slow, slower than loading a field from the cache-hot PACA, which happens to already contain the value we want in most cases. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-02 01:33:52 +01:00
ld r10,PACAKMSR(r13) /* Get kernel MSR without EE */
mtmsrd r10,1 /* Update machine state */
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#endif /* CONFIG_PPC_BOOK3E */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
#ifdef CONFIG_PREEMPT
clrrdi r9,r1,THREAD_SHIFT /* current_thread_info() */
li r0,_TIF_NEED_RESCHED /* bits to check */
ld r3,_MSR(r1)
ld r4,TI_FLAGS(r9)
/* Move MSR_PR bit in r3 to _TIF_SIGPENDING position in r0 */
rlwimi r0,r3,32+TIF_SIGPENDING-MSR_PR_LG,_TIF_SIGPENDING
and. r0,r4,r0 /* check NEED_RESCHED and maybe SIGPENDING */
bne do_work
#else /* !CONFIG_PREEMPT */
ld r3,_MSR(r1) /* Returning to user mode? */
andi. r3,r3,MSR_PR
beq restore /* if not, just restore regs and return */
/* Check current_thread_info()->flags */
clrrdi r9,r1,THREAD_SHIFT
ld r4,TI_FLAGS(r9)
andi. r0,r4,_TIF_USER_WORK_MASK
bne do_work
powerpc: Remove legacy iSeries bits from assembly files This removes the various bits of assembly in the kernel entry, exception handling and SLB management code that were specific to running under the legacy iSeries hypervisor which is no longer supported. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-28 03:44:58 +01:00
#endif /* !CONFIG_PREEMPT */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 08:27:59 +01:00
.globl fast_exc_return_irq
fast_exc_return_irq:
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
restore:
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 08:27:59 +01:00
/*
* This is the main kernel exit path, we first check if we
* have to change our interrupt state.
*/
powerpc: Streamline ret_from_except_lite for non-iSeries platforms There is a small passage of code in ret_from_except_lite which is only required on iSeries. For a multi-platform kernel on non-iSeries machines this means we end up executing ~15 nops in ret_from_except_lite. It would be nicer if non-iSeries could skip the code entirely, and on iSeries we can jump out of line to execute the code. I have no performance numbers to justify this, other than the assertion that executing 15 nops takes longer than executing 0. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-16 06:21:34 +02:00
ld r5,SOFTE(r1)
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 08:27:59 +01:00
lbz r6,PACASOFTIRQEN(r13)
cmpwi cr1,r5,0
cmpw cr0,r5,r6
beq cr0,4f
/* We do, handle disable first, which is easy */
bne cr1,3f;
li r0,0
stb r0,PACASOFTIRQEN(r13);
TRACE_DISABLE_INTS
b 4f
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 08:27:59 +01:00
3: /*
* We are about to soft-enable interrupts (we are hard disabled
* at this point). We check if there's anything that needs to
* be replayed first.
*/
lbz r0,PACAIRQHAPPENED(r13)
cmpwi cr0,r0,0
bne- restore_check_irq_replay
[POWERPC] Clear RI bit in MSR before restoring r13 when returning to userspace Some instruction tracing tools use the RI (recoverable interrupt) bit in the MSR to indicate when it's safe to single-step. Currently we clear RI after restoring r13 when returning to userspace. However, if we single-step past the point where r13 is restored, we'll corrupt r13 in the exception entry code and not restore it. This moves the clearing of RI to just before r13 is restored so this doesn't happen. Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-02-07 03:13:26 +01:00
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 08:27:59 +01:00
/*
* Get here when nothing happened while soft-disabled, just
* soft-enable and move-on. We will hard-enable as a side
* effect of rfi
*/
restore_no_replay:
TRACE_ENABLE_INTS
li r0,1
stb r0,PACASOFTIRQEN(r13);
/*
* Final return path. BookE is handled in a different file
*/
4:
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#ifdef CONFIG_PPC_BOOK3E
b .exception_return_book3e
#else
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 08:27:59 +01:00
/*
* Clear the reservation. If we know the CPU tracks the address of
* the reservation then we can potentially save some cycles and use
* a larx. On POWER6 and POWER7 this is significantly faster.
*/
BEGIN_FTR_SECTION
stdcx. r0,0,r1 /* to clear the reservation */
FTR_SECTION_ELSE
ldarx r4,0,r1
ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
/*
* Some code path such as load_up_fpu or altivec return directly
* here. They run entirely hard disabled and do not alter the
* interrupt state. They also don't use lwarx/stwcx. and thus
* are known not to leave dangling reservations.
*/
.globl fast_exception_return
fast_exception_return:
ld r3,_MSR(r1)
[POWERPC] Clear RI bit in MSR before restoring r13 when returning to userspace Some instruction tracing tools use the RI (recoverable interrupt) bit in the MSR to indicate when it's safe to single-step. Currently we clear RI after restoring r13 when returning to userspace. However, if we single-step past the point where r13 is restored, we'll corrupt r13 in the exception entry code and not restore it. This moves the clearing of RI to just before r13 is restored so this doesn't happen. Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-02-07 03:13:26 +01:00
ld r4,_CTR(r1)
ld r0,_LINK(r1)
mtctr r4
mtlr r0
ld r4,_XER(r1)
mtspr SPRN_XER,r4
REST_8GPRS(5, r1)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
andi. r0,r3,MSR_RI
beq- unrecov_restore
[POWERPC] Clear RI bit in MSR before restoring r13 when returning to userspace Some instruction tracing tools use the RI (recoverable interrupt) bit in the MSR to indicate when it's safe to single-step. Currently we clear RI after restoring r13 when returning to userspace. However, if we single-step past the point where r13 is restored, we'll corrupt r13 in the exception entry code and not restore it. This moves the clearing of RI to just before r13 is restored so this doesn't happen. Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-02-07 03:13:26 +01:00
/*
* Clear RI before restoring r13. If we are returning to
* userspace and we take an exception after restoring r13,
* we end up corrupting the userspace r13 value.
*/
powerpc: Replace mfmsr instructions with load from PACA kernel_msr field On 64-bit, the mfmsr instruction can be quite slow, slower than loading a field from the cache-hot PACA, which happens to already contain the value we want in most cases. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-02 01:33:52 +01:00
ld r4,PACAKMSR(r13) /* Get kernel MSR without EE */
andc r4,r4,r0 /* r0 contains MSR_RI here */
[POWERPC] Clear RI bit in MSR before restoring r13 when returning to userspace Some instruction tracing tools use the RI (recoverable interrupt) bit in the MSR to indicate when it's safe to single-step. Currently we clear RI after restoring r13 when returning to userspace. However, if we single-step past the point where r13 is restored, we'll corrupt r13 in the exception entry code and not restore it. This moves the clearing of RI to just before r13 is restored so this doesn't happen. Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-02-07 03:13:26 +01:00
mtmsrd r4,1
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
/*
* r13 is our per cpu area, only restore it if we are returning to
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 08:27:59 +01:00
* userspace the value stored in the stack frame may belong to
* another CPU.
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
*/
[POWERPC] Clear RI bit in MSR before restoring r13 when returning to userspace Some instruction tracing tools use the RI (recoverable interrupt) bit in the MSR to indicate when it's safe to single-step. Currently we clear RI after restoring r13 when returning to userspace. However, if we single-step past the point where r13 is restored, we'll corrupt r13 in the exception entry code and not restore it. This moves the clearing of RI to just before r13 is restored so this doesn't happen. Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-02-07 03:13:26 +01:00
andi. r0,r3,MSR_PR
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
beq 1f
[POWERPC] Clear RI bit in MSR before restoring r13 when returning to userspace Some instruction tracing tools use the RI (recoverable interrupt) bit in the MSR to indicate when it's safe to single-step. Currently we clear RI after restoring r13 when returning to userspace. However, if we single-step past the point where r13 is restored, we'll corrupt r13 in the exception entry code and not restore it. This moves the clearing of RI to just before r13 is restored so this doesn't happen. Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-02-07 03:13:26 +01:00
ACCOUNT_CPU_USER_EXIT(r2, r4)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
REST_GPR(13, r1)
1:
[POWERPC] Clear RI bit in MSR before restoring r13 when returning to userspace Some instruction tracing tools use the RI (recoverable interrupt) bit in the MSR to indicate when it's safe to single-step. Currently we clear RI after restoring r13 when returning to userspace. However, if we single-step past the point where r13 is restored, we'll corrupt r13 in the exception entry code and not restore it. This moves the clearing of RI to just before r13 is restored so this doesn't happen. Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-02-07 03:13:26 +01:00
mtspr SPRN_SRR1,r3
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
ld r2,_CCR(r1)
mtcrf 0xFF,r2
ld r2,_NIP(r1)
mtspr SPRN_SRR0,r2
ld r0,GPR0(r1)
ld r2,GPR2(r1)
ld r3,GPR3(r1)
ld r4,GPR4(r1)
ld r1,GPR1(r1)
rfid
b . /* prevent speculative execution */
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#endif /* CONFIG_PPC_BOOK3E */
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 08:27:59 +01:00
/*
* Something did happen, check if a re-emit is needed
* (this also clears paca->irq_happened)
*/
restore_check_irq_replay:
/* XXX: We could implement a fast path here where we check
* for irq_happened being just 0x01, in which case we can
* clear it and return. That means that we would potentially
* miss a decrementer having wrapped all the way around.
*
* Still, this might be useful for things like hash_page
*/
bl .__check_irq_replay
cmpwi cr0,r3,0
beq restore_no_replay
/*
* We need to re-emit an interrupt. We do so by re-using our
* existing exception frame. We first change the trap value,
* but we need to ensure we preserve the low nibble of it
*/
ld r4,_TRAP(r1)
clrldi r4,r4,60
or r4,r4,r3
std r4,_TRAP(r1)
/*
* Then find the right handler and call it. Interrupts are
* still soft-disabled and we keep them that way.
*/
cmpwi cr0,r3,0x500
bne 1f
addi r3,r1,STACK_FRAME_OVERHEAD;
bl .do_IRQ
b .ret_from_except
1: cmpwi cr0,r3,0x900
bne 1f
addi r3,r1,STACK_FRAME_OVERHEAD;
bl .timer_interrupt
b .ret_from_except
#ifdef CONFIG_PPC_BOOK3E
1: cmpwi cr0,r3,0x280
bne 1f
addi r3,r1,STACK_FRAME_OVERHEAD;
bl .doorbell_exception
b .ret_from_except
#endif /* CONFIG_PPC_BOOK3E */
1: b .ret_from_except /* What else to do here ? */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
do_work:
#ifdef CONFIG_PREEMPT
andi. r0,r3,MSR_PR /* Returning to user mode? */
bne user_work
/* Check that preempt_count() == 0 and interrupts are enabled */
lwz r8,TI_PREEMPT(r9)
cmpwi cr1,r8,0
ld r0,SOFTE(r1)
cmpdi r0,0
crandc eq,cr1*4+eq,eq
bne restore
powerpc/ppc64: Use preempt_schedule_irq instead of preempt_schedule Based on an original patch by Valentine Barshak <vbarshak@ru.mvista.com> Use preempt_schedule_irq to prevent infinite irq-entry and eventual stack overflow problems with fast-paced IRQ sources. This kind of problems has been observed on the PASemi Electra IDE controller. We have to make sure we are soft-disabled before calling preempt_schedule_irq and hard disable interrupts after that to avoid unrecoverable exceptions. This patch also moves the "clrrdi r9,r1,THREAD_SHIFT" out of the #ifdef CONFIG_PPC_BOOK3E scope, since r9 is clobbered and has to be restored in both cases. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-10-26 20:41:17 +01:00
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 08:27:59 +01:00
/*
* Here we are preempting the current task. We want to make
* sure we are soft-disabled first
[POWERPC] irqtrace support for 64-bit powerpc This adds the low level irq tracing hooks to the powerpc architecture needed to enable full lockdep functionality. This is partly based on Johannes Berg's initial version. I removed the asm trampoline that isn't needed (thus improving performance) and modified all sorts of bits and pieces, reworking most of the assembly, etc... Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-17 06:35:01 +02:00
*/
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 08:27:59 +01:00
SOFT_DISABLE_INTS(r3,r4)
powerpc/ppc64: Use preempt_schedule_irq instead of preempt_schedule Based on an original patch by Valentine Barshak <vbarshak@ru.mvista.com> Use preempt_schedule_irq to prevent infinite irq-entry and eventual stack overflow problems with fast-paced IRQ sources. This kind of problems has been observed on the PASemi Electra IDE controller. We have to make sure we are soft-disabled before calling preempt_schedule_irq and hard disable interrupts after that to avoid unrecoverable exceptions. This patch also moves the "clrrdi r9,r1,THREAD_SHIFT" out of the #ifdef CONFIG_PPC_BOOK3E scope, since r9 is clobbered and has to be restored in both cases. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-10-26 20:41:17 +01:00
1: bl .preempt_schedule_irq
/* Hard-disable interrupts again (and update PACA) */
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#ifdef CONFIG_PPC_BOOK3E
wrteei 0
#else
powerpc: Replace mfmsr instructions with load from PACA kernel_msr field On 64-bit, the mfmsr instruction can be quite slow, slower than loading a field from the cache-hot PACA, which happens to already contain the value we want in most cases. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-02 01:33:52 +01:00
ld r10,PACAKMSR(r13) /* Get kernel MSR without EE */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
mtmsrd r10,1
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#endif /* CONFIG_PPC_BOOK3E */
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 08:27:59 +01:00
li r0,PACA_IRQ_HARD_DIS
stb r0,PACAIRQHAPPENED(r13)
powerpc/ppc64: Use preempt_schedule_irq instead of preempt_schedule Based on an original patch by Valentine Barshak <vbarshak@ru.mvista.com> Use preempt_schedule_irq to prevent infinite irq-entry and eventual stack overflow problems with fast-paced IRQ sources. This kind of problems has been observed on the PASemi Electra IDE controller. We have to make sure we are soft-disabled before calling preempt_schedule_irq and hard disable interrupts after that to avoid unrecoverable exceptions. This patch also moves the "clrrdi r9,r1,THREAD_SHIFT" out of the #ifdef CONFIG_PPC_BOOK3E scope, since r9 is clobbered and has to be restored in both cases. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-10-26 20:41:17 +01:00
/* Re-test flags and eventually loop */
clrrdi r9,r1,THREAD_SHIFT
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
ld r4,TI_FLAGS(r9)
andi. r0,r4,_TIF_NEED_RESCHED
bne 1b
b restore
user_work:
powerpc/ppc64: Use preempt_schedule_irq instead of preempt_schedule Based on an original patch by Valentine Barshak <vbarshak@ru.mvista.com> Use preempt_schedule_irq to prevent infinite irq-entry and eventual stack overflow problems with fast-paced IRQ sources. This kind of problems has been observed on the PASemi Electra IDE controller. We have to make sure we are soft-disabled before calling preempt_schedule_irq and hard disable interrupts after that to avoid unrecoverable exceptions. This patch also moves the "clrrdi r9,r1,THREAD_SHIFT" out of the #ifdef CONFIG_PPC_BOOK3E scope, since r9 is clobbered and has to be restored in both cases. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-10-26 20:41:17 +01:00
#endif /* CONFIG_PREEMPT */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
/* Enable interrupts */
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#ifdef CONFIG_PPC_BOOK3E
wrteei 1
#else
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
ori r10,r10,MSR_EE
mtmsrd r10,1
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#endif /* CONFIG_PPC_BOOK3E */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
andi. r0,r4,_TIF_NEED_RESCHED
beq 1f
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 08:27:59 +01:00
bl .restore_interrupts
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
bl .schedule
b .ret_from_except_lite
1: bl .save_nvgprs
powerpc: Rework lazy-interrupt handling The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
2012-03-06 08:27:59 +01:00
bl .restore_interrupts
powerpc: Add TIF_NOTIFY_RESUME support for tracehook This adds TIF_NOTIFY_RESUME support for powerpc. When set, we call tracehook_notify_resume() on the way to user mode. This overloads do_signal() to do the work, but changes its arguments to it has the TIF_* bits handy in a register and drops the useless first argument that was always zero. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-27 08:52:52 +02:00
addi r3,r1,STACK_FRAME_OVERHEAD
powerpc: Fix various issues with return to userspace We have a few problems when returning to userspace. This is a quick set of fixes for 3.3, I'll look into a more comprehensive rework for 3.4. This fixes: - We kept interrupts soft-disabled when schedule'ing or calling do_signal when returning to userspace as a result of a hardware interrupt. - Rename do_signal to do_notify_resume like all other archs (and do_signal_pending back to do_signal, which it was before Roland changed it). - Add the missing call to key_replace_session_keyring() to do_notify_resume(). Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> ---
2012-02-22 06:48:32 +01:00
bl .do_notify_resume
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
b .ret_from_except
unrecov_restore:
addi r3,r1,STACK_FRAME_OVERHEAD
bl .unrecoverable_exception
b unrecov_restore
#ifdef CONFIG_PPC_RTAS
/*
* On CHRP, the Run-Time Abstraction Services (RTAS) have to be
* called with the MMU off.
*
* In addition, we need to be in 32b mode, at least for now.
*
* Note: r3 is an input parameter to rtas, so don't trash it...
*/
_GLOBAL(enter_rtas)
mflr r0
std r0,16(r1)
stdu r1,-RTAS_FRAME_SIZE(r1) /* Save SP and create stack space. */
/* Because RTAS is running in 32b mode, it clobbers the high order half
* of all registers that it saves. We therefore save those registers
* RTAS might touch to the stack. (r0, r3-r13 are caller saved)
*/
SAVE_GPR(2, r1) /* Save the TOC */
SAVE_GPR(13, r1) /* Save paca */
SAVE_8GPRS(14, r1) /* Save the non-volatiles */
SAVE_10GPRS(22, r1) /* ditto */
mfcr r4
std r4,_CCR(r1)
mfctr r5
std r5,_CTR(r1)
mfspr r6,SPRN_XER
std r6,_XER(r1)
mfdar r7
std r7,_DAR(r1)
mfdsisr r8
std r8,_DSISR(r1)
[PATCH] powerpc: Workaround for pSeries RTAS bug A bug in the RTAS services incorrectly interprets some bits in the CR when called from the OS. Specifically, bits in CR4. The result could be a firmware crash that also takes down the partition. A firmware fix is in the works. We have seen this situation when performing DLPAR operations. As a temporary workaround, clear the CR in enter_rtas(). Note that enter_rtas() will not set any bits in CR4 before calling RTAS. Also note that the 32 bit version of enter_rtas() should have the same work around even though the chances of hitting the bug are much smaller due to the lack of DLPAR on 32 bit kernels. However, my assembly skills are a bit rusty and the 32 bit code doesn't seem to follow the conventions for where things should be saved. In addition, I don't have a system to test 32 bit kernels. Help creating and at least touch testing the same workaround for 32 bit would be appreciated. Signed-off-by: Mike Kravetz <kravetz@us.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-28 01:20:00 +02:00
/* Temporary workaround to clear CR until RTAS can be modified to
* ignore all bits.
*/
li r0,0
mtcr r0
[POWERPC] Fix manual assembly WARN_ON() in enter_rtas(). When we switched over to the generic BUG mechanism we forgot to change the assembly code which open-codes a WARN_ON() in enter_rtas(), so the bug table got corrupted. This patch provides an EMIT_BUG_ENTRY macro for use in assembly code, and uses it in entry_64.S. Tested with CONFIG_DEBUG_BUGVERBOSE on ppc64 but not without -- I tried to turn it off but it wouldn't go away; I suspect Aunt Tillie probably needed it. This version gets __FILE__ and __LINE__ right in the assembly version -- rather than saying include/asm-powerpc/bug.h line 21 every time which is a little suboptimal. Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-01-01 19:45:34 +01:00
#ifdef CONFIG_BUG
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
/* There is no way it is acceptable to get here with interrupts enabled,
* check it with the asm equivalent of WARN_ON
*/
[POWERPC] Lazy interrupt disabling for 64-bit machines This implements a lazy strategy for disabling interrupts. This means that local_irq_disable() et al. just clear the 'interrupts are enabled' flag in the paca. If an interrupt comes along, the interrupt entry code notices that interrupts are supposed to be disabled, and clears the EE bit in SRR1, clears the 'interrupts are hard-enabled' flag in the paca, and returns. This means that interrupts only actually get disabled in the processor when an interrupt comes along. When interrupts are enabled by local_irq_enable() et al., the code sets the interrupts-enabled flag in the paca, and then checks whether interrupts got hard-disabled. If so, it also sets the EE bit in the MSR to hard-enable the interrupts. This has the potential to improve performance, and also makes it easier to make a kernel that can boot on iSeries and on other 64-bit machines, since this lazy-disable strategy is very similar to the soft-disable strategy that iSeries already uses. This version renames paca->proc_enabled to paca->soft_enabled, and changes a couple of soft-disables in the kexec code to hard-disables, which should fix the crash that Michael Ellerman saw. This doesn't yet use a reserved CR field for the soft_enabled and hard_enabled flags. This applies on top of Stephen Rothwell's patches to make it possible to build a combined iSeries/other kernel. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-10-04 08:47:49 +02:00
lbz r0,PACASOFTIRQEN(r13)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
1: tdnei r0,0
[POWERPC] Fix manual assembly WARN_ON() in enter_rtas(). When we switched over to the generic BUG mechanism we forgot to change the assembly code which open-codes a WARN_ON() in enter_rtas(), so the bug table got corrupted. This patch provides an EMIT_BUG_ENTRY macro for use in assembly code, and uses it in entry_64.S. Tested with CONFIG_DEBUG_BUGVERBOSE on ppc64 but not without -- I tried to turn it off but it wouldn't go away; I suspect Aunt Tillie probably needed it. This version gets __FILE__ and __LINE__ right in the assembly version -- rather than saying include/asm-powerpc/bug.h line 21 every time which is a little suboptimal. Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-01-01 19:45:34 +01:00
EMIT_BUG_ENTRY 1b,__FILE__,__LINE__,BUGFLAG_WARNING
#endif
[POWERPC] Lazy interrupt disabling for 64-bit machines This implements a lazy strategy for disabling interrupts. This means that local_irq_disable() et al. just clear the 'interrupts are enabled' flag in the paca. If an interrupt comes along, the interrupt entry code notices that interrupts are supposed to be disabled, and clears the EE bit in SRR1, clears the 'interrupts are hard-enabled' flag in the paca, and returns. This means that interrupts only actually get disabled in the processor when an interrupt comes along. When interrupts are enabled by local_irq_enable() et al., the code sets the interrupts-enabled flag in the paca, and then checks whether interrupts got hard-disabled. If so, it also sets the EE bit in the MSR to hard-enable the interrupts. This has the potential to improve performance, and also makes it easier to make a kernel that can boot on iSeries and on other 64-bit machines, since this lazy-disable strategy is very similar to the soft-disable strategy that iSeries already uses. This version renames paca->proc_enabled to paca->soft_enabled, and changes a couple of soft-disables in the kexec code to hard-disables, which should fix the crash that Michael Ellerman saw. This doesn't yet use a reserved CR field for the soft_enabled and hard_enabled flags. This applies on top of Stephen Rothwell's patches to make it possible to build a combined iSeries/other kernel. Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-10-04 08:47:49 +02:00
/* Hard-disable interrupts */
mfmsr r6
rldicl r7,r6,48,1
rotldi r7,r7,16
mtmsrd r7,1
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
/* Unfortunately, the stack pointer and the MSR are also clobbered,
* so they are saved in the PACA which allows us to restore
* our original state after RTAS returns.
*/
std r1,PACAR1(r13)
std r6,PACASAVEDMSR(r13)
/* Setup our real return addr */
[PATCH] powerpc: Cleanup LOADADDR etc. asm macros This patch consolidates the variety of macros used for loading 32 or 64-bit constants in assembler (LOADADDR, LOADBASE, SET_REG_TO_*). The idea is to make the set of macros consistent across 32 and 64 bit and to make it more obvious which is the appropriate one to use in a given situation. The new macros and their semantics are described in the comments in ppc_asm.h. In the process, we change several places that were unnecessarily using immediate loads on ppc64 to use the GOT/TOC. Likewise we cleanup a couple of places where we were clumsily subtracting PAGE_OFFSET with asm instructions to use assemble-time arithmetic or the toreal() macro instead. Signed-off-by: David Gibson <dwg@au1.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-01-13 04:56:25 +01:00
LOAD_REG_ADDR(r4,.rtas_return_loc)
clrldi r4,r4,2 /* convert to realmode address */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
mtlr r4
li r0,0
ori r0,r0,MSR_EE|MSR_SE|MSR_BE|MSR_RI
andc r0,r6,r0
li r9,1
rldicr r9,r9,MSR_SF_LG,(63-MSR_SF_LG)
powerpc: Clear MSR_RI during RTAS calls RTAS should never cause an exception but if it does (for example accessing outside our RMO) then we might go a long way through the kernel before oopsing. If we unset MSR_RI we should at least stop things on exception exit. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-02-07 20:37:29 +01:00
ori r9,r9,MSR_IR|MSR_DR|MSR_FE0|MSR_FE1|MSR_FP|MSR_RI
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
andc r6,r0,r9
sync /* disable interrupts so SRR0/1 */
mtmsrd r0 /* don't get trashed */
[PATCH] powerpc: Cleanup LOADADDR etc. asm macros This patch consolidates the variety of macros used for loading 32 or 64-bit constants in assembler (LOADADDR, LOADBASE, SET_REG_TO_*). The idea is to make the set of macros consistent across 32 and 64 bit and to make it more obvious which is the appropriate one to use in a given situation. The new macros and their semantics are described in the comments in ppc_asm.h. In the process, we change several places that were unnecessarily using immediate loads on ppc64 to use the GOT/TOC. Likewise we cleanup a couple of places where we were clumsily subtracting PAGE_OFFSET with asm instructions to use assemble-time arithmetic or the toreal() macro instead. Signed-off-by: David Gibson <dwg@au1.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-01-13 04:56:25 +01:00
LOAD_REG_ADDR(r4, rtas)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
ld r5,RTASENTRY(r4) /* get the rtas->entry value */
ld r4,RTASBASE(r4) /* get the rtas->base value */
mtspr SPRN_SRR0,r5
mtspr SPRN_SRR1,r6
rfid
b . /* prevent speculative execution */
_STATIC(rtas_return_loc)
/* relocation is off at this point */
powerpc: In HV mode, use HSPRG0 for PACA When running in Hypervisor mode (arch 2.06 or later), we store the PACA in HSPRG0 instead of SPRG1. The architecture specifies that SPRGs may be lost during a "nap" power management operation (though they aren't currently on POWER7) and this enables use of SPRG1 by KVM guests. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-01-20 07:50:21 +01:00
GET_PACA(r4)
[PATCH] powerpc: Cleanup LOADADDR etc. asm macros This patch consolidates the variety of macros used for loading 32 or 64-bit constants in assembler (LOADADDR, LOADBASE, SET_REG_TO_*). The idea is to make the set of macros consistent across 32 and 64 bit and to make it more obvious which is the appropriate one to use in a given situation. The new macros and their semantics are described in the comments in ppc_asm.h. In the process, we change several places that were unnecessarily using immediate loads on ppc64 to use the GOT/TOC. Likewise we cleanup a couple of places where we were clumsily subtracting PAGE_OFFSET with asm instructions to use assemble-time arithmetic or the toreal() macro instead. Signed-off-by: David Gibson <dwg@au1.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-01-13 04:56:25 +01:00
clrldi r4,r4,2 /* convert to realmode address */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
powerpc: Use LOAD_REG_IMMEDIATE only for constants on 64-bit Using LOAD_REG_IMMEDIATE to get the address of kernel symbols generates 5 instructions where LOAD_REG_ADDR can do it in one, and will generate R_PPC64_ADDR16_* relocations in the output when we get to making the kernel as a position-independent executable, which we'd rather not have to handle. This changes various bits of assembly code to use LOAD_REG_ADDR when we need to get the address of a symbol, or to use suitable position-independent code for cases where we can't access the TOC for various reasons, or if we're not running at the address we were linked at. It also cleans up a few minor things; there's no reason to save and restore SRR0/1 around RTAS calls, __mmu_off can get the return address from LR more conveniently than the caller can supply it in R4 (and we already assume elsewhere that EA == RA if the MMU is on in early boot), and enable_64b_mode was using 5 instructions where 2 would do. Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-08-30 03:41:12 +02:00
bcl 20,31,$+4
0: mflr r3
ld r3,(1f-0b)(r3) /* get &.rtas_restore_regs */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
mfmsr r6
li r0,MSR_RI
andc r6,r6,r0
sync
mtmsrd r6
ld r1,PACAR1(r4) /* Restore our SP */
ld r4,PACASAVEDMSR(r4) /* Restore our MSR */
mtspr SPRN_SRR0,r3
mtspr SPRN_SRR1,r4
rfid
b . /* prevent speculative execution */
powerpc: Use LOAD_REG_IMMEDIATE only for constants on 64-bit Using LOAD_REG_IMMEDIATE to get the address of kernel symbols generates 5 instructions where LOAD_REG_ADDR can do it in one, and will generate R_PPC64_ADDR16_* relocations in the output when we get to making the kernel as a position-independent executable, which we'd rather not have to handle. This changes various bits of assembly code to use LOAD_REG_ADDR when we need to get the address of a symbol, or to use suitable position-independent code for cases where we can't access the TOC for various reasons, or if we're not running at the address we were linked at. It also cleans up a few minor things; there's no reason to save and restore SRR0/1 around RTAS calls, __mmu_off can get the return address from LR more conveniently than the caller can supply it in R4 (and we already assume elsewhere that EA == RA if the MMU is on in early boot), and enable_64b_mode was using 5 instructions where 2 would do. Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-08-30 03:41:12 +02:00
.align 3
1: .llong .rtas_restore_regs
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
_STATIC(rtas_restore_regs)
/* relocation is on at this point */
REST_GPR(2, r1) /* Restore the TOC */
REST_GPR(13, r1) /* Restore paca */
REST_8GPRS(14, r1) /* Restore the non-volatiles */
REST_10GPRS(22, r1) /* ditto */
powerpc: In HV mode, use HSPRG0 for PACA When running in Hypervisor mode (arch 2.06 or later), we store the PACA in HSPRG0 instead of SPRG1. The architecture specifies that SPRGs may be lost during a "nap" power management operation (though they aren't currently on POWER7) and this enables use of SPRG1 by KVM guests. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-01-20 07:50:21 +01:00
GET_PACA(r13)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
ld r4,_CCR(r1)
mtcr r4
ld r5,_CTR(r1)
mtctr r5
ld r6,_XER(r1)
mtspr SPRN_XER,r6
ld r7,_DAR(r1)
mtdar r7
ld r8,_DSISR(r1)
mtdsisr r8
addi r1,r1,RTAS_FRAME_SIZE /* Unstack our frame */
ld r0,16(r1) /* get return address */
mtlr r0
blr /* return to caller */
#endif /* CONFIG_PPC_RTAS */
_GLOBAL(enter_prom)
mflr r0
std r0,16(r1)
stdu r1,-PROM_FRAME_SIZE(r1) /* Save SP and create stack space */
/* Because PROM is running in 32b mode, it clobbers the high order half
* of all registers that it saves. We therefore save those registers
* PROM might touch to the stack. (r0, r3-r13 are caller saved)
*/
powerpc/of: Remove useless register save/restore when calling OF back enter_prom() used to save and restore registers such as CTR, XER etc.. which are volatile, or SRR0,1... which we don't care about. This removes a bunch of useless code and while at it turns an mtmsrd into an MTMSRD macro which will be useful to Book3E. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:07 +02:00
SAVE_GPR(2, r1)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
SAVE_GPR(13, r1)
SAVE_8GPRS(14, r1)
SAVE_10GPRS(22, r1)
powerpc/of: Remove useless register save/restore when calling OF back enter_prom() used to save and restore registers such as CTR, XER etc.. which are volatile, or SRR0,1... which we don't care about. This removes a bunch of useless code and while at it turns an mtmsrd into an MTMSRD macro which will be useful to Book3E. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:07 +02:00
mfcr r10
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
mfmsr r11
powerpc/of: Remove useless register save/restore when calling OF back enter_prom() used to save and restore registers such as CTR, XER etc.. which are volatile, or SRR0,1... which we don't care about. This removes a bunch of useless code and while at it turns an mtmsrd into an MTMSRD macro which will be useful to Book3E. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:07 +02:00
std r10,_CCR(r1)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
std r11,_MSR(r1)
/* Get the PROM entrypoint */
powerpc/of: Remove useless register save/restore when calling OF back enter_prom() used to save and restore registers such as CTR, XER etc.. which are volatile, or SRR0,1... which we don't care about. This removes a bunch of useless code and while at it turns an mtmsrd into an MTMSRD macro which will be useful to Book3E. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:07 +02:00
mtlr r4
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
/* Switch MSR to 32 bits mode
*/
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#ifdef CONFIG_PPC_BOOK3E
rlwinm r11,r11,0,1,31
mtmsr r11
#else /* CONFIG_PPC_BOOK3E */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
mfmsr r11
li r12,1
rldicr r12,r12,MSR_SF_LG,(63-MSR_SF_LG)
andc r11,r11,r12
li r12,1
rldicr r12,r12,MSR_ISF_LG,(63-MSR_ISF_LG)
andc r11,r11,r12
mtmsrd r11
powerpc: Remaining 64-bit Book3E support This contains all the bits that didn't fit in previous patches :-) This includes the actual exception handlers assembly, the changes to the kernel entry, other misc bits and wiring it all up in Kconfig. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:59 +02:00
#endif /* CONFIG_PPC_BOOK3E */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
isync
powerpc/of: Remove useless register save/restore when calling OF back enter_prom() used to save and restore registers such as CTR, XER etc.. which are volatile, or SRR0,1... which we don't care about. This removes a bunch of useless code and while at it turns an mtmsrd into an MTMSRD macro which will be useful to Book3E. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:07 +02:00
/* Enter PROM here... */
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
blrl
/* Just make sure that r1 top 32 bits didn't get
* corrupt by OF
*/
rldicl r1,r1,0,32
/* Restore the MSR (back to 64 bits) */
ld r0,_MSR(r1)
powerpc/of: Remove useless register save/restore when calling OF back enter_prom() used to save and restore registers such as CTR, XER etc.. which are volatile, or SRR0,1... which we don't care about. This removes a bunch of useless code and while at it turns an mtmsrd into an MTMSRD macro which will be useful to Book3E. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-07-24 01:15:07 +02:00
MTMSRD(r0)
powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S The system call table has been consolidated into systbl.S. We have separate 32-bit and 64-bit versions of entry.S and misc.S since the code is mostly sufficiently different to be not worth merging. There are some common bits that will be extracted in future. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-10 14:36:14 +02:00
isync
/* Restore other registers */
REST_GPR(2, r1)
REST_GPR(13, r1)
REST_8GPRS(14, r1)
REST_10GPRS(22, r1)
ld r4,_CCR(r1)
mtcr r4
addi r1,r1,PROM_FRAME_SIZE
ld r0,16(r1)
mtlr r0
blr
ftrace: support for PowerPC This patch adds full support for ftrace for PowerPC (both 64 and 32 bit). This includes dynamic tracing and function filtering. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-15 05:49:44 +02:00
ftrace: rename FTRACE to FUNCTION_TRACER Due to confusion between the ftrace infrastructure and the gcc profiling tracer "ftrace", this patch renames the config options from FTRACE to FUNCTION_TRACER. The other two names that are offspring from FTRACE DYNAMIC_FTRACE and FTRACE_MCOUNT_RECORD will stay the same. This patch was generated mostly by script, and partially by hand. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-07 01:06:12 +02:00
#ifdef CONFIG_FUNCTION_TRACER
ftrace: support for PowerPC This patch adds full support for ftrace for PowerPC (both 64 and 32 bit). This includes dynamic tracing and function filtering. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-15 05:49:44 +02:00
#ifdef CONFIG_DYNAMIC_FTRACE
_GLOBAL(mcount)
_GLOBAL(_mcount)
blr
_GLOBAL(ftrace_caller)
/* Taken from output of objdump from lib64/glibc */
mflr r3
ld r11, 0(r1)
stdu r1, -112(r1)
std r3, 128(r1)
ld r4, 16(r11)
ftrace: store mcount address in rec->ip Record the address of the mcount call-site. Currently all archs except sparc64 record the address of the instruction following the mcount call-site. Some general cleanups are entailed. Storing mcount addresses in rec->ip enables looking them up in the kprobe hash table later on to check if they're kprobe'd. Signed-off-by: Abhishek Sagar <sagar.abhishek@gmail.com> Cc: davem@davemloft.net Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-21 20:17:27 +02:00
subi r3, r3, MCOUNT_INSN_SIZE
ftrace: support for PowerPC This patch adds full support for ftrace for PowerPC (both 64 and 32 bit). This includes dynamic tracing and function filtering. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-15 05:49:44 +02:00
.globl ftrace_call
ftrace_call:
bl ftrace_stub
nop
powerpc64, tracing: add function graph tracer with dynamic tracing This is the port of the function graph tracer to PowerPC with dynamic tracing. Geoff Lavand tested on PS3. Tested-by: Geoff Levand <geoffrey.levand@am.sony.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-11 07:19:54 +01:00
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
.globl ftrace_graph_call
ftrace_graph_call:
b ftrace_graph_stub
_GLOBAL(ftrace_graph_stub)
#endif
ftrace: support for PowerPC This patch adds full support for ftrace for PowerPC (both 64 and 32 bit). This includes dynamic tracing and function filtering. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-15 05:49:44 +02:00
ld r0, 128(r1)
mtlr r0
addi r1, r1, 112
_GLOBAL(ftrace_stub)
blr
#else
_GLOBAL(mcount)
blr
_GLOBAL(_mcount)
/* Taken from output of objdump from lib64/glibc */
mflr r3
ld r11, 0(r1)
stdu r1, -112(r1)
std r3, 128(r1)
ld r4, 16(r11)
ftrace: store mcount address in rec->ip Record the address of the mcount call-site. Currently all archs except sparc64 record the address of the instruction following the mcount call-site. Some general cleanups are entailed. Storing mcount addresses in rec->ip enables looking them up in the kprobe hash table later on to check if they're kprobe'd. Signed-off-by: Abhishek Sagar <sagar.abhishek@gmail.com> Cc: davem@davemloft.net Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-21 20:17:27 +02:00
subi r3, r3, MCOUNT_INSN_SIZE
ftrace: support for PowerPC This patch adds full support for ftrace for PowerPC (both 64 and 32 bit). This includes dynamic tracing and function filtering. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-15 05:49:44 +02:00
LOAD_REG_ADDR(r5,ftrace_trace_function)
ld r5,0(r5)
ld r5,0(r5)
mtctr r5
bctrl
nop
powerpc64: port of the function graph tracer This is a port of the function graph tracer that was written by Frederic Weisbecker for the x86. This only works for PPC64 at the moment and only for static tracing. PPC32 and dynamic function graph tracing support will come later. The trace produces a visual calling of functions: # tracer: function_graph # # CPU DURATION FUNCTION CALLS # | | | | | | | 0) 2.224 us | } 0) ! 271.024 us | } 0) ! 320.080 us | } 0) ! 324.656 us | } 0) ! 329.136 us | } 0) | .put_prev_task_fair() { 0) | .update_curr() { 0) 2.240 us | .update_min_vruntime(); 0) 6.512 us | } 0) 2.528 us | .__enqueue_entity(); 0) + 15.536 us | } 0) | .pick_next_task_fair() { 0) 2.032 us | .__pick_next_entity(); 0) 2.064 us | .__clear_buddies(); 0) | .set_next_entity() { 0) 2.672 us | .__dequeue_entity(); 0) 6.864 us | } Geoff Lavand tested on PS3. Tested-by: Geoff Levand <geoffrey.levand@am.sony.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-10 06:10:27 +01:00
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
b ftrace_graph_caller
#endif
ftrace: support for PowerPC This patch adds full support for ftrace for PowerPC (both 64 and 32 bit). This includes dynamic tracing and function filtering. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-15 05:49:44 +02:00
ld r0, 128(r1)
mtlr r0
addi r1, r1, 112
_GLOBAL(ftrace_stub)
blr
powerpc64: port of the function graph tracer This is a port of the function graph tracer that was written by Frederic Weisbecker for the x86. This only works for PPC64 at the moment and only for static tracing. PPC32 and dynamic function graph tracing support will come later. The trace produces a visual calling of functions: # tracer: function_graph # # CPU DURATION FUNCTION CALLS # | | | | | | | 0) 2.224 us | } 0) ! 271.024 us | } 0) ! 320.080 us | } 0) ! 324.656 us | } 0) ! 329.136 us | } 0) | .put_prev_task_fair() { 0) | .update_curr() { 0) 2.240 us | .update_min_vruntime(); 0) 6.512 us | } 0) 2.528 us | .__enqueue_entity(); 0) + 15.536 us | } 0) | .pick_next_task_fair() { 0) 2.032 us | .__pick_next_entity(); 0) 2.064 us | .__clear_buddies(); 0) | .set_next_entity() { 0) 2.672 us | .__dequeue_entity(); 0) 6.864 us | } Geoff Lavand tested on PS3. Tested-by: Geoff Levand <geoffrey.levand@am.sony.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-10 06:10:27 +01:00
#endif /* CONFIG_DYNAMIC_FTRACE */
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
powerpc64, tracing: add function graph tracer with dynamic tracing This is the port of the function graph tracer to PowerPC with dynamic tracing. Geoff Lavand tested on PS3. Tested-by: Geoff Levand <geoffrey.levand@am.sony.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-11 07:19:54 +01:00
_GLOBAL(ftrace_graph_caller)
powerpc64: port of the function graph tracer This is a port of the function graph tracer that was written by Frederic Weisbecker for the x86. This only works for PPC64 at the moment and only for static tracing. PPC32 and dynamic function graph tracing support will come later. The trace produces a visual calling of functions: # tracer: function_graph # # CPU DURATION FUNCTION CALLS # | | | | | | | 0) 2.224 us | } 0) ! 271.024 us | } 0) ! 320.080 us | } 0) ! 324.656 us | } 0) ! 329.136 us | } 0) | .put_prev_task_fair() { 0) | .update_curr() { 0) 2.240 us | .update_min_vruntime(); 0) 6.512 us | } 0) 2.528 us | .__enqueue_entity(); 0) + 15.536 us | } 0) | .pick_next_task_fair() { 0) 2.032 us | .__pick_next_entity(); 0) 2.064 us | .__clear_buddies(); 0) | .set_next_entity() { 0) 2.672 us | .__dequeue_entity(); 0) 6.864 us | } Geoff Lavand tested on PS3. Tested-by: Geoff Levand <geoffrey.levand@am.sony.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-10 06:10:27 +01:00
/* load r4 with local address */
ld r4, 128(r1)
subi r4, r4, MCOUNT_INSN_SIZE
/* get the parent address */
ld r11, 112(r1)
addi r3, r11, 16
bl .prepare_ftrace_return
nop
ld r0, 128(r1)
mtlr r0
addi r1, r1, 112
blr
_GLOBAL(return_to_handler)
powerpc64, ftrace: save toc only on modules for function graph The TOCS used by modules are different than the one used by the core kernel code. The function graph tracer must save and restore the TOC whenever it traces a module call. But this is an added overhead to burden the majority of core kernel code being traced. Benjamin Herrenschmidt suggested in testing the entry of the call to tell if it is a core kernel function or a module. He recommended using the REGION_ID() macro to perform this test. This patch implements Benjamin's idea, and uses a different return_to_handler routine dependent on if the entry is a core kernel function or not. The module version saves the TOC, where as the core kernel version does not. Geoff Lavand tested on PS3. Tested-by: Geoff Levand <geoffrey.levand@am.sony.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-11 21:45:49 +01:00
/* need to save return values */
std r4, -24(r1)
std r3, -16(r1)
std r31, -8(r1)
mr r31, r1
stdu r1, -112(r1)
bl .ftrace_return_to_handler
nop
/* return value has real return address */
mtlr r3
ld r1, 0(r1)
ld r4, -24(r1)
ld r3, -16(r1)
ld r31, -8(r1)
/* Jump back to real return address */
blr
_GLOBAL(mod_return_to_handler)
powerpc64: port of the function graph tracer This is a port of the function graph tracer that was written by Frederic Weisbecker for the x86. This only works for PPC64 at the moment and only for static tracing. PPC32 and dynamic function graph tracing support will come later. The trace produces a visual calling of functions: # tracer: function_graph # # CPU DURATION FUNCTION CALLS # | | | | | | | 0) 2.224 us | } 0) ! 271.024 us | } 0) ! 320.080 us | } 0) ! 324.656 us | } 0) ! 329.136 us | } 0) | .put_prev_task_fair() { 0) | .update_curr() { 0) 2.240 us | .update_min_vruntime(); 0) 6.512 us | } 0) 2.528 us | .__enqueue_entity(); 0) + 15.536 us | } 0) | .pick_next_task_fair() { 0) 2.032 us | .__pick_next_entity(); 0) 2.064 us | .__clear_buddies(); 0) | .set_next_entity() { 0) 2.672 us | .__dequeue_entity(); 0) 6.864 us | } Geoff Lavand tested on PS3. Tested-by: Geoff Levand <geoffrey.levand@am.sony.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-10 06:10:27 +01:00
/* need to save return values */
std r4, -32(r1)
std r3, -24(r1)
/* save TOC */
std r2, -16(r1)
std r31, -8(r1)
mr r31, r1
stdu r1, -112(r1)
powerpc64, ftrace: save toc only on modules for function graph The TOCS used by modules are different than the one used by the core kernel code. The function graph tracer must save and restore the TOC whenever it traces a module call. But this is an added overhead to burden the majority of core kernel code being traced. Benjamin Herrenschmidt suggested in testing the entry of the call to tell if it is a core kernel function or a module. He recommended using the REGION_ID() macro to perform this test. This patch implements Benjamin's idea, and uses a different return_to_handler routine dependent on if the entry is a core kernel function or not. The module version saves the TOC, where as the core kernel version does not. Geoff Lavand tested on PS3. Tested-by: Geoff Levand <geoffrey.levand@am.sony.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-11 21:45:49 +01:00
/*
* We are in a module using the module's TOC.
* Switch to our TOC to run inside the core kernel.
*/
powerpc64/ftrace: use PACA to retrieve TOC in mod_return_to_handler The mod_return_to_handler needs to switch to the kernel TOC before jumping to a the kernel code. It currently does this by looking at the kernel function data and retrieves the TOC that way. Not only is this inefficient, it also breaks with a relocatable kernel. The PACA contains the kernel TOC and we can easily retrieve it that way. Reported-by: Sachin Sant <sachinp@in.ibm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-15 17:30:14 +02:00
ld r2, PACATOC(r13)
powerpc64: port of the function graph tracer This is a port of the function graph tracer that was written by Frederic Weisbecker for the x86. This only works for PPC64 at the moment and only for static tracing. PPC32 and dynamic function graph tracing support will come later. The trace produces a visual calling of functions: # tracer: function_graph # # CPU DURATION FUNCTION CALLS # | | | | | | | 0) 2.224 us | } 0) ! 271.024 us | } 0) ! 320.080 us | } 0) ! 324.656 us | } 0) ! 329.136 us | } 0) | .put_prev_task_fair() { 0) | .update_curr() { 0) 2.240 us | .update_min_vruntime(); 0) 6.512 us | } 0) 2.528 us | .__enqueue_entity(); 0) + 15.536 us | } 0) | .pick_next_task_fair() { 0) 2.032 us | .__pick_next_entity(); 0) 2.064 us | .__clear_buddies(); 0) | .set_next_entity() { 0) 2.672 us | .__dequeue_entity(); 0) 6.864 us | } Geoff Lavand tested on PS3. Tested-by: Geoff Levand <geoffrey.levand@am.sony.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-10 06:10:27 +01:00
bl .ftrace_return_to_handler
nop
/* return value has real return address */
mtlr r3
ld r1, 0(r1)
ld r4, -32(r1)
ld r3, -24(r1)
ld r2, -16(r1)
ld r31, -8(r1)
/* Jump back to real return address */
blr
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
#endif /* CONFIG_FUNCTION_TRACER */
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