Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into perf/core

This commit is contained in:
Ingo Molnar 2010-09-24 09:12:05 +02:00
commit a5a2bad55d
33 changed files with 843 additions and 209 deletions

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@ -591,6 +591,11 @@ KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)
# conserve stack if available
KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)
# check for 'asm goto'
ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC)), y)
KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
endif
# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
# But warn user when we do so
warn-assign = \

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@ -158,4 +158,7 @@ config HAVE_PERF_EVENTS_NMI
subsystem. Also has support for calculating CPU cycle events
to determine how many clock cycles in a given period.
config HAVE_ARCH_JUMP_LABEL
bool
source "kernel/gcov/Kconfig"

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@ -30,6 +30,7 @@ config SPARC
select PERF_USE_VMALLOC
select HAVE_DMA_ATTRS
select HAVE_DMA_API_DEBUG
select HAVE_ARCH_JUMP_LABEL
config SPARC32
def_bool !64BIT

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@ -0,0 +1,32 @@
#ifndef _ASM_SPARC_JUMP_LABEL_H
#define _ASM_SPARC_JUMP_LABEL_H
#ifdef __KERNEL__
#include <linux/types.h>
#include <asm/system.h>
#define JUMP_LABEL_NOP_SIZE 4
#define JUMP_LABEL(key, label) \
do { \
asm goto("1:\n\t" \
"nop\n\t" \
"nop\n\t" \
".pushsection __jump_table, \"a\"\n\t"\
".word 1b, %l[" #label "], %c0\n\t" \
".popsection \n\t" \
: : "i" (key) : : label);\
} while (0)
#endif /* __KERNEL__ */
typedef u32 jump_label_t;
struct jump_entry {
jump_label_t code;
jump_label_t target;
jump_label_t key;
};
#endif

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@ -119,3 +119,5 @@ obj-$(CONFIG_COMPAT) += $(audit--y)
pc--$(CONFIG_PERF_EVENTS) := perf_event.o
obj-$(CONFIG_SPARC64) += $(pc--y)
obj-$(CONFIG_SPARC64) += jump_label.o

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@ -0,0 +1,47 @@
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/mutex.h>
#include <linux/cpu.h>
#include <linux/jump_label.h>
#include <linux/memory.h>
#ifdef HAVE_JUMP_LABEL
void arch_jump_label_transform(struct jump_entry *entry,
enum jump_label_type type)
{
u32 val;
u32 *insn = (u32 *) (unsigned long) entry->code;
if (type == JUMP_LABEL_ENABLE) {
s32 off = (s32)entry->target - (s32)entry->code;
#ifdef CONFIG_SPARC64
/* ba,pt %xcc, . + (off << 2) */
val = 0x10680000 | ((u32) off >> 2);
#else
/* ba . + (off << 2) */
val = 0x10800000 | ((u32) off >> 2);
#endif
} else {
val = 0x01000000;
}
get_online_cpus();
mutex_lock(&text_mutex);
*insn = val;
flushi(insn);
mutex_unlock(&text_mutex);
put_online_cpus();
}
void arch_jump_label_text_poke_early(jump_label_t addr)
{
u32 *insn_p = (u32 *) (unsigned long) addr;
*insn_p = 0x01000000;
flushi(insn_p);
}
#endif

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@ -18,6 +18,9 @@
#include <asm/spitfire.h>
#ifdef CONFIG_SPARC64
#include <linux/jump_label.h>
static void *module_map(unsigned long size)
{
struct vm_struct *area;
@ -227,6 +230,9 @@ int module_finalize(const Elf_Ehdr *hdr,
const Elf_Shdr *sechdrs,
struct module *me)
{
/* make jump label nops */
jump_label_apply_nops(me);
/* Cheetah's I-cache is fully coherent. */
if (tlb_type == spitfire) {
unsigned long va;

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@ -59,6 +59,7 @@ config X86
select ANON_INODES
select HAVE_ARCH_KMEMCHECK
select HAVE_USER_RETURN_NOTIFIER
select HAVE_ARCH_JUMP_LABEL
config INSTRUCTION_DECODER
def_bool (KPROBES || PERF_EVENTS)

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@ -4,6 +4,7 @@
#include <linux/types.h>
#include <linux/stddef.h>
#include <linux/stringify.h>
#include <linux/jump_label.h>
#include <asm/asm.h>
/*
@ -160,6 +161,8 @@ static inline void apply_paravirt(struct paravirt_patch_site *start,
#define __parainstructions_end NULL
#endif
extern void *text_poke_early(void *addr, const void *opcode, size_t len);
/*
* Clear and restore the kernel write-protection flag on the local CPU.
* Allows the kernel to edit read-only pages.
@ -180,4 +183,12 @@ static inline void apply_paravirt(struct paravirt_patch_site *start,
extern void *text_poke(void *addr, const void *opcode, size_t len);
extern void *text_poke_smp(void *addr, const void *opcode, size_t len);
#if defined(CONFIG_DYNAMIC_FTRACE) || defined(HAVE_JUMP_LABEL)
#define IDEAL_NOP_SIZE_5 5
extern unsigned char ideal_nop5[IDEAL_NOP_SIZE_5];
extern void arch_init_ideal_nop5(void);
#else
static inline void arch_init_ideal_nop5(void) {}
#endif
#endif /* _ASM_X86_ALTERNATIVE_H */

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@ -0,0 +1,37 @@
#ifndef _ASM_X86_JUMP_LABEL_H
#define _ASM_X86_JUMP_LABEL_H
#ifdef __KERNEL__
#include <linux/types.h>
#include <asm/nops.h>
#define JUMP_LABEL_NOP_SIZE 5
# define JUMP_LABEL_INITIAL_NOP ".byte 0xe9 \n\t .long 0\n\t"
# define JUMP_LABEL(key, label) \
do { \
asm goto("1:" \
JUMP_LABEL_INITIAL_NOP \
".pushsection __jump_table, \"a\" \n\t"\
_ASM_PTR "1b, %l[" #label "], %c0 \n\t" \
".popsection \n\t" \
: : "i" (key) : : label); \
} while (0)
#endif /* __KERNEL__ */
#ifdef CONFIG_X86_64
typedef u64 jump_label_t;
#else
typedef u32 jump_label_t;
#endif
struct jump_entry {
jump_label_t code;
jump_label_t target;
jump_label_t key;
};
#endif

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@ -32,7 +32,7 @@ GCOV_PROFILE_paravirt.o := n
obj-y := process_$(BITS).o signal.o entry_$(BITS).o
obj-y += traps.o irq.o irq_$(BITS).o dumpstack_$(BITS).o
obj-y += time.o ioport.o ldt.o dumpstack.o
obj-y += setup.o x86_init.o i8259.o irqinit.o
obj-y += setup.o x86_init.o i8259.o irqinit.o jump_label.o
obj-$(CONFIG_X86_VISWS) += visws_quirks.o
obj-$(CONFIG_X86_32) += probe_roms_32.o
obj-$(CONFIG_X86_32) += sys_i386_32.o i386_ksyms_32.o

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@ -195,7 +195,7 @@ static void __init_or_module add_nops(void *insns, unsigned int len)
extern struct alt_instr __alt_instructions[], __alt_instructions_end[];
extern s32 __smp_locks[], __smp_locks_end[];
static void *text_poke_early(void *addr, const void *opcode, size_t len);
void *text_poke_early(void *addr, const void *opcode, size_t len);
/* Replace instructions with better alternatives for this CPU type.
This runs before SMP is initialized to avoid SMP problems with
@ -522,7 +522,7 @@ void __init alternative_instructions(void)
* instructions. And on the local CPU you need to be protected again NMI or MCE
* handlers seeing an inconsistent instruction while you patch.
*/
static void *__init_or_module text_poke_early(void *addr, const void *opcode,
void *__init_or_module text_poke_early(void *addr, const void *opcode,
size_t len)
{
unsigned long flags;
@ -641,3 +641,67 @@ void *__kprobes text_poke_smp(void *addr, const void *opcode, size_t len)
return addr;
}
#if defined(CONFIG_DYNAMIC_FTRACE) || defined(HAVE_JUMP_LABEL)
unsigned char ideal_nop5[IDEAL_NOP_SIZE_5];
void __init arch_init_ideal_nop5(void)
{
extern const unsigned char ftrace_test_p6nop[];
extern const unsigned char ftrace_test_nop5[];
extern const unsigned char ftrace_test_jmp[];
int faulted = 0;
/*
* There is no good nop for all x86 archs.
* We will default to using the P6_NOP5, but first we
* will test to make sure that the nop will actually
* work on this CPU. If it faults, we will then
* go to a lesser efficient 5 byte nop. If that fails
* we then just use a jmp as our nop. This isn't the most
* efficient nop, but we can not use a multi part nop
* since we would then risk being preempted in the middle
* of that nop, and if we enabled tracing then, it might
* cause a system crash.
*
* TODO: check the cpuid to determine the best nop.
*/
asm volatile (
"ftrace_test_jmp:"
"jmp ftrace_test_p6nop\n"
"nop\n"
"nop\n"
"nop\n" /* 2 byte jmp + 3 bytes */
"ftrace_test_p6nop:"
P6_NOP5
"jmp 1f\n"
"ftrace_test_nop5:"
".byte 0x66,0x66,0x66,0x66,0x90\n"
"1:"
".section .fixup, \"ax\"\n"
"2: movl $1, %0\n"
" jmp ftrace_test_nop5\n"
"3: movl $2, %0\n"
" jmp 1b\n"
".previous\n"
_ASM_EXTABLE(ftrace_test_p6nop, 2b)
_ASM_EXTABLE(ftrace_test_nop5, 3b)
: "=r"(faulted) : "0" (faulted));
switch (faulted) {
case 0:
pr_info("converting mcount calls to 0f 1f 44 00 00\n");
memcpy(ideal_nop5, ftrace_test_p6nop, IDEAL_NOP_SIZE_5);
break;
case 1:
pr_info("converting mcount calls to 66 66 66 66 90\n");
memcpy(ideal_nop5, ftrace_test_nop5, IDEAL_NOP_SIZE_5);
break;
case 2:
pr_info("converting mcount calls to jmp . + 5\n");
memcpy(ideal_nop5, ftrace_test_jmp, IDEAL_NOP_SIZE_5);
break;
}
}
#endif

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@ -257,14 +257,9 @@ do_ftrace_mod_code(unsigned long ip, void *new_code)
return mod_code_status;
}
static unsigned char ftrace_nop[MCOUNT_INSN_SIZE];
static unsigned char *ftrace_nop_replace(void)
{
return ftrace_nop;
return ideal_nop5;
}
static int
@ -338,62 +333,6 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
int __init ftrace_dyn_arch_init(void *data)
{
extern const unsigned char ftrace_test_p6nop[];
extern const unsigned char ftrace_test_nop5[];
extern const unsigned char ftrace_test_jmp[];
int faulted = 0;
/*
* There is no good nop for all x86 archs.
* We will default to using the P6_NOP5, but first we
* will test to make sure that the nop will actually
* work on this CPU. If it faults, we will then
* go to a lesser efficient 5 byte nop. If that fails
* we then just use a jmp as our nop. This isn't the most
* efficient nop, but we can not use a multi part nop
* since we would then risk being preempted in the middle
* of that nop, and if we enabled tracing then, it might
* cause a system crash.
*
* TODO: check the cpuid to determine the best nop.
*/
asm volatile (
"ftrace_test_jmp:"
"jmp ftrace_test_p6nop\n"
"nop\n"
"nop\n"
"nop\n" /* 2 byte jmp + 3 bytes */
"ftrace_test_p6nop:"
P6_NOP5
"jmp 1f\n"
"ftrace_test_nop5:"
".byte 0x66,0x66,0x66,0x66,0x90\n"
"1:"
".section .fixup, \"ax\"\n"
"2: movl $1, %0\n"
" jmp ftrace_test_nop5\n"
"3: movl $2, %0\n"
" jmp 1b\n"
".previous\n"
_ASM_EXTABLE(ftrace_test_p6nop, 2b)
_ASM_EXTABLE(ftrace_test_nop5, 3b)
: "=r"(faulted) : "0" (faulted));
switch (faulted) {
case 0:
pr_info("converting mcount calls to 0f 1f 44 00 00\n");
memcpy(ftrace_nop, ftrace_test_p6nop, MCOUNT_INSN_SIZE);
break;
case 1:
pr_info("converting mcount calls to 66 66 66 66 90\n");
memcpy(ftrace_nop, ftrace_test_nop5, MCOUNT_INSN_SIZE);
break;
case 2:
pr_info("converting mcount calls to jmp . + 5\n");
memcpy(ftrace_nop, ftrace_test_jmp, MCOUNT_INSN_SIZE);
break;
}
/* The return code is retured via data */
*(unsigned long *)data = 0;

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@ -0,0 +1,50 @@
/*
* jump label x86 support
*
* Copyright (C) 2009 Jason Baron <jbaron@redhat.com>
*
*/
#include <linux/jump_label.h>
#include <linux/memory.h>
#include <linux/uaccess.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/jhash.h>
#include <linux/cpu.h>
#include <asm/kprobes.h>
#include <asm/alternative.h>
#ifdef HAVE_JUMP_LABEL
union jump_code_union {
char code[JUMP_LABEL_NOP_SIZE];
struct {
char jump;
int offset;
} __attribute__((packed));
};
void arch_jump_label_transform(struct jump_entry *entry,
enum jump_label_type type)
{
union jump_code_union code;
if (type == JUMP_LABEL_ENABLE) {
code.jump = 0xe9;
code.offset = entry->target -
(entry->code + JUMP_LABEL_NOP_SIZE);
} else
memcpy(&code, ideal_nop5, JUMP_LABEL_NOP_SIZE);
get_online_cpus();
mutex_lock(&text_mutex);
text_poke_smp((void *)entry->code, &code, JUMP_LABEL_NOP_SIZE);
mutex_unlock(&text_mutex);
put_online_cpus();
}
void arch_jump_label_text_poke_early(jump_label_t addr)
{
text_poke_early((void *)addr, ideal_nop5, JUMP_LABEL_NOP_SIZE);
}
#endif

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@ -1218,7 +1218,8 @@ static int __kprobes copy_optimized_instructions(u8 *dest, u8 *src)
}
/* Check whether the address range is reserved */
if (ftrace_text_reserved(src, src + len - 1) ||
alternatives_text_reserved(src, src + len - 1))
alternatives_text_reserved(src, src + len - 1) ||
jump_label_text_reserved(src, src + len - 1))
return -EBUSY;
return len;

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@ -239,6 +239,9 @@ int module_finalize(const Elf_Ehdr *hdr,
apply_paravirt(pseg, pseg + para->sh_size);
}
/* make jump label nops */
jump_label_apply_nops(me);
return module_bug_finalize(hdr, sechdrs, me);
}

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@ -112,6 +112,7 @@
#include <asm/numa_64.h>
#endif
#include <asm/mce.h>
#include <asm/alternative.h>
/*
* end_pfn only includes RAM, while max_pfn_mapped includes all e820 entries.
@ -726,6 +727,7 @@ void __init setup_arch(char **cmdline_p)
{
int acpi = 0;
int k8 = 0;
unsigned long flags;
#ifdef CONFIG_X86_32
memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
@ -1071,6 +1073,10 @@ void __init setup_arch(char **cmdline_p)
x86_init.oem.banner();
mcheck_init();
local_irq_save(flags);
arch_init_ideal_nop5();
local_irq_restore(flags);
}
#ifdef CONFIG_X86_32

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@ -220,6 +220,8 @@
\
BUG_TABLE \
\
JUMP_TABLE \
\
/* PCI quirks */ \
.pci_fixup : AT(ADDR(.pci_fixup) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start_pci_fixups_early) = .; \
@ -563,6 +565,14 @@
#define BUG_TABLE
#endif
#define JUMP_TABLE \
. = ALIGN(8); \
__jump_table : AT(ADDR(__jump_table) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start___jump_table) = .; \
*(__jump_table) \
VMLINUX_SYMBOL(__stop___jump_table) = .; \
}
#ifdef CONFIG_PM_TRACE
#define TRACEDATA \
. = ALIGN(4); \

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@ -1,6 +1,8 @@
#ifndef _DYNAMIC_DEBUG_H
#define _DYNAMIC_DEBUG_H
#include <linux/jump_label.h>
/* dynamic_printk_enabled, and dynamic_printk_enabled2 are bitmasks in which
* bit n is set to 1 if any modname hashes into the bucket n, 0 otherwise. They
* use independent hash functions, to reduce the chance of false positives.
@ -22,8 +24,6 @@ struct _ddebug {
const char *function;
const char *filename;
const char *format;
char primary_hash;
char secondary_hash;
unsigned int lineno:24;
/*
* The flags field controls the behaviour at the callsite.
@ -33,6 +33,7 @@ struct _ddebug {
#define _DPRINTK_FLAGS_PRINT (1<<0) /* printk() a message using the format */
#define _DPRINTK_FLAGS_DEFAULT 0
unsigned int flags:8;
char enabled;
} __attribute__((aligned(8)));
@ -42,33 +43,35 @@ int ddebug_add_module(struct _ddebug *tab, unsigned int n,
#if defined(CONFIG_DYNAMIC_DEBUG)
extern int ddebug_remove_module(const char *mod_name);
#define __dynamic_dbg_enabled(dd) ({ \
int __ret = 0; \
if (unlikely((dynamic_debug_enabled & (1LL << DEBUG_HASH)) && \
(dynamic_debug_enabled2 & (1LL << DEBUG_HASH2)))) \
if (unlikely(dd.flags)) \
__ret = 1; \
__ret; })
#define dynamic_pr_debug(fmt, ...) do { \
__label__ do_printk; \
__label__ out; \
static struct _ddebug descriptor \
__used \
__attribute__((section("__verbose"), aligned(8))) = \
{ KBUILD_MODNAME, __func__, __FILE__, fmt, DEBUG_HASH, \
DEBUG_HASH2, __LINE__, _DPRINTK_FLAGS_DEFAULT }; \
if (__dynamic_dbg_enabled(descriptor)) \
printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); \
{ KBUILD_MODNAME, __func__, __FILE__, fmt, __LINE__, \
_DPRINTK_FLAGS_DEFAULT }; \
JUMP_LABEL(&descriptor.enabled, do_printk); \
goto out; \
do_printk: \
printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); \
out: ; \
} while (0)
#define dynamic_dev_dbg(dev, fmt, ...) do { \
__label__ do_printk; \
__label__ out; \
static struct _ddebug descriptor \
__used \
__attribute__((section("__verbose"), aligned(8))) = \
{ KBUILD_MODNAME, __func__, __FILE__, fmt, DEBUG_HASH, \
DEBUG_HASH2, __LINE__, _DPRINTK_FLAGS_DEFAULT }; \
if (__dynamic_dbg_enabled(descriptor)) \
dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__); \
{ KBUILD_MODNAME, __func__, __FILE__, fmt, __LINE__, \
_DPRINTK_FLAGS_DEFAULT }; \
JUMP_LABEL(&descriptor.enabled, do_printk); \
goto out; \
do_printk: \
dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__); \
out: ; \
} while (0)
#else

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@ -0,0 +1,64 @@
#ifndef _LINUX_JUMP_LABEL_H
#define _LINUX_JUMP_LABEL_H
#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_HAVE_ARCH_JUMP_LABEL)
# include <asm/jump_label.h>
# define HAVE_JUMP_LABEL
#endif
enum jump_label_type {
JUMP_LABEL_ENABLE,
JUMP_LABEL_DISABLE
};
struct module;
#ifdef HAVE_JUMP_LABEL
extern struct jump_entry __start___jump_table[];
extern struct jump_entry __stop___jump_table[];
extern void arch_jump_label_transform(struct jump_entry *entry,
enum jump_label_type type);
extern void arch_jump_label_text_poke_early(jump_label_t addr);
extern void jump_label_update(unsigned long key, enum jump_label_type type);
extern void jump_label_apply_nops(struct module *mod);
extern int jump_label_text_reserved(void *start, void *end);
#define enable_jump_label(key) \
jump_label_update((unsigned long)key, JUMP_LABEL_ENABLE);
#define disable_jump_label(key) \
jump_label_update((unsigned long)key, JUMP_LABEL_DISABLE);
#else
#define JUMP_LABEL(key, label) \
do { \
if (unlikely(*key)) \
goto label; \
} while (0)
#define enable_jump_label(cond_var) \
do { \
*(cond_var) = 1; \
} while (0)
#define disable_jump_label(cond_var) \
do { \
*(cond_var) = 0; \
} while (0)
static inline int jump_label_apply_nops(struct module *mod)
{
return 0;
}
static inline int jump_label_text_reserved(void *start, void *end)
{
return 0;
}
#endif
#endif

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@ -350,7 +350,10 @@ struct module
struct tracepoint *tracepoints;
unsigned int num_tracepoints;
#endif
#ifdef HAVE_JUMP_LABEL
struct jump_entry *jump_entries;
unsigned int num_jump_entries;
#endif
#ifdef CONFIG_TRACING
const char **trace_bprintk_fmt_start;
unsigned int num_trace_bprintk_fmt;

View File

@ -17,6 +17,7 @@
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/rcupdate.h>
#include <linux/jump_label.h>
struct module;
struct tracepoint;
@ -145,7 +146,9 @@ static inline void tracepoint_update_probe_range(struct tracepoint *begin,
extern struct tracepoint __tracepoint_##name; \
static inline void trace_##name(proto) \
{ \
if (unlikely(__tracepoint_##name.state)) \
JUMP_LABEL(&__tracepoint_##name.state, do_trace); \
return; \
do_trace: \
__DO_TRACE(&__tracepoint_##name, \
TP_PROTO(data_proto), \
TP_ARGS(data_args)); \

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@ -10,7 +10,7 @@ obj-y = sched.o fork.o exec_domain.o panic.o printk.o \
kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \
hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
notifier.o ksysfs.o pm_qos_params.o sched_clock.o cred.o \
async.o range.o
async.o range.o jump_label.o
obj-$(CONFIG_HAVE_EARLY_RES) += early_res.o
obj-y += groups.o

429
kernel/jump_label.c Normal file
View File

@ -0,0 +1,429 @@
/*
* jump label support
*
* Copyright (C) 2009 Jason Baron <jbaron@redhat.com>
*
*/
#include <linux/jump_label.h>
#include <linux/memory.h>
#include <linux/uaccess.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/jhash.h>
#include <linux/slab.h>
#include <linux/sort.h>
#include <linux/err.h>
#ifdef HAVE_JUMP_LABEL
#define JUMP_LABEL_HASH_BITS 6
#define JUMP_LABEL_TABLE_SIZE (1 << JUMP_LABEL_HASH_BITS)
static struct hlist_head jump_label_table[JUMP_LABEL_TABLE_SIZE];
/* mutex to protect coming/going of the the jump_label table */
static DEFINE_MUTEX(jump_label_mutex);
struct jump_label_entry {
struct hlist_node hlist;
struct jump_entry *table;
int nr_entries;
/* hang modules off here */
struct hlist_head modules;
unsigned long key;
};
struct jump_label_module_entry {
struct hlist_node hlist;
struct jump_entry *table;
int nr_entries;
struct module *mod;
};
static int jump_label_cmp(const void *a, const void *b)
{
const struct jump_entry *jea = a;
const struct jump_entry *jeb = b;
if (jea->key < jeb->key)
return -1;
if (jea->key > jeb->key)
return 1;
return 0;
}
static void
sort_jump_label_entries(struct jump_entry *start, struct jump_entry *stop)
{
unsigned long size;
size = (((unsigned long)stop - (unsigned long)start)
/ sizeof(struct jump_entry));
sort(start, size, sizeof(struct jump_entry), jump_label_cmp, NULL);
}
static struct jump_label_entry *get_jump_label_entry(jump_label_t key)
{
struct hlist_head *head;
struct hlist_node *node;
struct jump_label_entry *e;
u32 hash = jhash((void *)&key, sizeof(jump_label_t), 0);
head = &jump_label_table[hash & (JUMP_LABEL_TABLE_SIZE - 1)];
hlist_for_each_entry(e, node, head, hlist) {
if (key == e->key)
return e;
}
return NULL;
}
static struct jump_label_entry *
add_jump_label_entry(jump_label_t key, int nr_entries, struct jump_entry *table)
{
struct hlist_head *head;
struct jump_label_entry *e;
u32 hash;
e = get_jump_label_entry(key);
if (e)
return ERR_PTR(-EEXIST);
e = kmalloc(sizeof(struct jump_label_entry), GFP_KERNEL);
if (!e)
return ERR_PTR(-ENOMEM);
hash = jhash((void *)&key, sizeof(jump_label_t), 0);
head = &jump_label_table[hash & (JUMP_LABEL_TABLE_SIZE - 1)];
e->key = key;
e->table = table;
e->nr_entries = nr_entries;
INIT_HLIST_HEAD(&(e->modules));
hlist_add_head(&e->hlist, head);
return e;
}
static int
build_jump_label_hashtable(struct jump_entry *start, struct jump_entry *stop)
{
struct jump_entry *iter, *iter_begin;
struct jump_label_entry *entry;
int count;
sort_jump_label_entries(start, stop);
iter = start;
while (iter < stop) {
entry = get_jump_label_entry(iter->key);
if (!entry) {
iter_begin = iter;
count = 0;
while ((iter < stop) &&
(iter->key == iter_begin->key)) {
iter++;
count++;
}
entry = add_jump_label_entry(iter_begin->key,
count, iter_begin);
if (IS_ERR(entry))
return PTR_ERR(entry);
} else {
WARN_ONCE(1, KERN_ERR "build_jump_hashtable: unexpected entry!\n");
return -1;
}
}
return 0;
}
/***
* jump_label_update - update jump label text
* @key - key value associated with a a jump label
* @type - enum set to JUMP_LABEL_ENABLE or JUMP_LABEL_DISABLE
*
* Will enable/disable the jump for jump label @key, depending on the
* value of @type.
*
*/
void jump_label_update(unsigned long key, enum jump_label_type type)
{
struct jump_entry *iter;
struct jump_label_entry *entry;
struct hlist_node *module_node;
struct jump_label_module_entry *e_module;
int count;
mutex_lock(&jump_label_mutex);
entry = get_jump_label_entry((jump_label_t)key);
if (entry) {
count = entry->nr_entries;
iter = entry->table;
while (count--) {
if (kernel_text_address(iter->code))
arch_jump_label_transform(iter, type);
iter++;
}
/* eanble/disable jump labels in modules */
hlist_for_each_entry(e_module, module_node, &(entry->modules),
hlist) {
count = e_module->nr_entries;
iter = e_module->table;
while (count--) {
if (kernel_text_address(iter->code))
arch_jump_label_transform(iter, type);
iter++;
}
}
}
mutex_unlock(&jump_label_mutex);
}
static int addr_conflict(struct jump_entry *entry, void *start, void *end)
{
if (entry->code <= (unsigned long)end &&
entry->code + JUMP_LABEL_NOP_SIZE > (unsigned long)start)
return 1;
return 0;
}
#ifdef CONFIG_MODULES
static int module_conflict(void *start, void *end)
{
struct hlist_head *head;
struct hlist_node *node, *node_next, *module_node, *module_node_next;
struct jump_label_entry *e;
struct jump_label_module_entry *e_module;
struct jump_entry *iter;
int i, count;
int conflict = 0;
for (i = 0; i < JUMP_LABEL_TABLE_SIZE; i++) {
head = &jump_label_table[i];
hlist_for_each_entry_safe(e, node, node_next, head, hlist) {
hlist_for_each_entry_safe(e_module, module_node,
module_node_next,
&(e->modules), hlist) {
count = e_module->nr_entries;
iter = e_module->table;
while (count--) {
if (addr_conflict(iter, start, end)) {
conflict = 1;
goto out;
}
iter++;
}
}
}
}
out:
return conflict;
}
#endif
/***
* jump_label_text_reserved - check if addr range is reserved
* @start: start text addr
* @end: end text addr
*
* checks if the text addr located between @start and @end
* overlaps with any of the jump label patch addresses. Code
* that wants to modify kernel text should first verify that
* it does not overlap with any of the jump label addresses.
*
* returns 1 if there is an overlap, 0 otherwise
*/
int jump_label_text_reserved(void *start, void *end)
{
struct jump_entry *iter;
struct jump_entry *iter_start = __start___jump_table;
struct jump_entry *iter_stop = __start___jump_table;
int conflict = 0;
mutex_lock(&jump_label_mutex);
iter = iter_start;
while (iter < iter_stop) {
if (addr_conflict(iter, start, end)) {
conflict = 1;
goto out;
}
iter++;
}
/* now check modules */
#ifdef CONFIG_MODULES
conflict = module_conflict(start, end);
#endif
out:
mutex_unlock(&jump_label_mutex);
return conflict;
}
static __init int init_jump_label(void)
{
int ret;
struct jump_entry *iter_start = __start___jump_table;
struct jump_entry *iter_stop = __stop___jump_table;
struct jump_entry *iter;
mutex_lock(&jump_label_mutex);
ret = build_jump_label_hashtable(__start___jump_table,
__stop___jump_table);
iter = iter_start;
while (iter < iter_stop) {
arch_jump_label_text_poke_early(iter->code);
iter++;
}
mutex_unlock(&jump_label_mutex);
return ret;
}
early_initcall(init_jump_label);
#ifdef CONFIG_MODULES
static struct jump_label_module_entry *
add_jump_label_module_entry(struct jump_label_entry *entry,
struct jump_entry *iter_begin,
int count, struct module *mod)
{
struct jump_label_module_entry *e;
e = kmalloc(sizeof(struct jump_label_module_entry), GFP_KERNEL);
if (!e)
return ERR_PTR(-ENOMEM);
e->mod = mod;
e->nr_entries = count;
e->table = iter_begin;
hlist_add_head(&e->hlist, &entry->modules);
return e;
}
static int add_jump_label_module(struct module *mod)
{
struct jump_entry *iter, *iter_begin;
struct jump_label_entry *entry;
struct jump_label_module_entry *module_entry;
int count;
/* if the module doesn't have jump label entries, just return */
if (!mod->num_jump_entries)
return 0;
sort_jump_label_entries(mod->jump_entries,
mod->jump_entries + mod->num_jump_entries);
iter = mod->jump_entries;
while (iter < mod->jump_entries + mod->num_jump_entries) {
entry = get_jump_label_entry(iter->key);
iter_begin = iter;
count = 0;
while ((iter < mod->jump_entries + mod->num_jump_entries) &&
(iter->key == iter_begin->key)) {
iter++;
count++;
}
if (!entry) {
entry = add_jump_label_entry(iter_begin->key, 0, NULL);
if (IS_ERR(entry))
return PTR_ERR(entry);
}
module_entry = add_jump_label_module_entry(entry, iter_begin,
count, mod);
if (IS_ERR(module_entry))
return PTR_ERR(module_entry);
}
return 0;
}
static void remove_jump_label_module(struct module *mod)
{
struct hlist_head *head;
struct hlist_node *node, *node_next, *module_node, *module_node_next;
struct jump_label_entry *e;
struct jump_label_module_entry *e_module;
int i;
/* if the module doesn't have jump label entries, just return */
if (!mod->num_jump_entries)
return;
for (i = 0; i < JUMP_LABEL_TABLE_SIZE; i++) {
head = &jump_label_table[i];
hlist_for_each_entry_safe(e, node, node_next, head, hlist) {
hlist_for_each_entry_safe(e_module, module_node,
module_node_next,
&(e->modules), hlist) {
if (e_module->mod == mod) {
hlist_del(&e_module->hlist);
kfree(e_module);
}
}
if (hlist_empty(&e->modules) && (e->nr_entries == 0)) {
hlist_del(&e->hlist);
kfree(e);
}
}
}
}
static int
jump_label_module_notify(struct notifier_block *self, unsigned long val,
void *data)
{
struct module *mod = data;
int ret = 0;
switch (val) {
case MODULE_STATE_COMING:
mutex_lock(&jump_label_mutex);
ret = add_jump_label_module(mod);
if (ret)
remove_jump_label_module(mod);
mutex_unlock(&jump_label_mutex);
break;
case MODULE_STATE_GOING:
mutex_lock(&jump_label_mutex);
remove_jump_label_module(mod);
mutex_unlock(&jump_label_mutex);
break;
}
return ret;
}
/***
* apply_jump_label_nops - patch module jump labels with arch_get_jump_label_nop()
* @mod: module to patch
*
* Allow for run-time selection of the optimal nops. Before the module
* loads patch these with arch_get_jump_label_nop(), which is specified by
* the arch specific jump label code.
*/
void jump_label_apply_nops(struct module *mod)
{
struct jump_entry *iter;
/* if the module doesn't have jump label entries, just return */
if (!mod->num_jump_entries)
return;
iter = mod->jump_entries;
while (iter < mod->jump_entries + mod->num_jump_entries) {
arch_jump_label_text_poke_early(iter->code);
iter++;
}
}
struct notifier_block jump_label_module_nb = {
.notifier_call = jump_label_module_notify,
.priority = 0,
};
static __init int init_jump_label_module(void)
{
return register_module_notifier(&jump_label_module_nb);
}
early_initcall(init_jump_label_module);
#endif /* CONFIG_MODULES */
#endif

View File

@ -47,6 +47,7 @@
#include <linux/memory.h>
#include <linux/ftrace.h>
#include <linux/cpu.h>
#include <linux/jump_label.h>
#include <asm-generic/sections.h>
#include <asm/cacheflush.h>
@ -1146,7 +1147,8 @@ int __kprobes register_kprobe(struct kprobe *p)
preempt_disable();
if (!kernel_text_address((unsigned long) p->addr) ||
in_kprobes_functions((unsigned long) p->addr) ||
ftrace_text_reserved(p->addr, p->addr)) {
ftrace_text_reserved(p->addr, p->addr) ||
jump_label_text_reserved(p->addr, p->addr)) {
preempt_enable();
return -EINVAL;
}

View File

@ -55,6 +55,7 @@
#include <linux/async.h>
#include <linux/percpu.h>
#include <linux/kmemleak.h>
#include <linux/jump_label.h>
#define CREATE_TRACE_POINTS
#include <trace/events/module.h>
@ -2308,6 +2309,11 @@ static void find_module_sections(struct module *mod, struct load_info *info)
sizeof(*mod->tracepoints),
&mod->num_tracepoints);
#endif
#ifdef HAVE_JUMP_LABEL
mod->jump_entries = section_objs(info, "__jump_table",
sizeof(*mod->jump_entries),
&mod->num_jump_entries);
#endif
#ifdef CONFIG_EVENT_TRACING
mod->trace_events = section_objs(info, "_ftrace_events",
sizeof(*mod->trace_events),

View File

@ -263,6 +263,11 @@ int __init trace_workqueue_early_init(void)
{
int ret, cpu;
for_each_possible_cpu(cpu) {
spin_lock_init(&workqueue_cpu_stat(cpu)->lock);
INIT_LIST_HEAD(&workqueue_cpu_stat(cpu)->list);
}
ret = register_trace_workqueue_insertion(probe_workqueue_insertion, NULL);
if (ret)
goto out;
@ -279,11 +284,6 @@ int __init trace_workqueue_early_init(void)
if (ret)
goto no_creation;
for_each_possible_cpu(cpu) {
spin_lock_init(&workqueue_cpu_stat(cpu)->lock);
INIT_LIST_HEAD(&workqueue_cpu_stat(cpu)->list);
}
return 0;
no_creation:

View File

@ -25,6 +25,7 @@
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/jump_label.h>
extern struct tracepoint __start___tracepoints[];
extern struct tracepoint __stop___tracepoints[];
@ -263,7 +264,13 @@ static void set_tracepoint(struct tracepoint_entry **entry,
* is used.
*/
rcu_assign_pointer(elem->funcs, (*entry)->funcs);
elem->state = active;
if (!elem->state && active) {
enable_jump_label(&elem->state);
elem->state = active;
} else if (elem->state && !active) {
disable_jump_label(&elem->state);
elem->state = active;
}
}
/*
@ -277,7 +284,10 @@ static void disable_tracepoint(struct tracepoint *elem)
if (elem->unregfunc && elem->state)
elem->unregfunc();
elem->state = 0;
if (elem->state) {
disable_jump_label(&elem->state);
elem->state = 0;
}
rcu_assign_pointer(elem->funcs, NULL);
}

View File

@ -26,19 +26,11 @@
#include <linux/dynamic_debug.h>
#include <linux/debugfs.h>
#include <linux/slab.h>
#include <linux/jump_label.h>
extern struct _ddebug __start___verbose[];
extern struct _ddebug __stop___verbose[];
/* dynamic_debug_enabled, and dynamic_debug_enabled2 are bitmasks in which
* bit n is set to 1 if any modname hashes into the bucket n, 0 otherwise. They
* use independent hash functions, to reduce the chance of false positives.
*/
long long dynamic_debug_enabled;
EXPORT_SYMBOL_GPL(dynamic_debug_enabled);
long long dynamic_debug_enabled2;
EXPORT_SYMBOL_GPL(dynamic_debug_enabled2);
struct ddebug_table {
struct list_head link;
char *mod_name;
@ -87,26 +79,6 @@ static char *ddebug_describe_flags(struct _ddebug *dp, char *buf,
return buf;
}
/*
* must be called with ddebug_lock held
*/
static int disabled_hash(char hash, bool first_table)
{
struct ddebug_table *dt;
char table_hash_value;
list_for_each_entry(dt, &ddebug_tables, link) {
if (first_table)
table_hash_value = dt->ddebugs->primary_hash;
else
table_hash_value = dt->ddebugs->secondary_hash;
if (dt->num_enabled && (hash == table_hash_value))
return 0;
}
return 1;
}
/*
* Search the tables for _ddebug's which match the given
* `query' and apply the `flags' and `mask' to them. Tells
@ -170,17 +142,9 @@ static void ddebug_change(const struct ddebug_query *query,
dt->num_enabled++;
dp->flags = newflags;
if (newflags) {
dynamic_debug_enabled |=
(1LL << dp->primary_hash);
dynamic_debug_enabled2 |=
(1LL << dp->secondary_hash);
enable_jump_label(&dp->enabled);
} else {
if (disabled_hash(dp->primary_hash, true))
dynamic_debug_enabled &=
~(1LL << dp->primary_hash);
if (disabled_hash(dp->secondary_hash, false))
dynamic_debug_enabled2 &=
~(1LL << dp->secondary_hash);
disable_jump_label(&dp->enabled);
}
if (verbose)
printk(KERN_INFO

View File

@ -101,14 +101,6 @@ basename_flags = -D"KBUILD_BASENAME=KBUILD_STR($(call name-fix,$(basetarget)))"
modname_flags = $(if $(filter 1,$(words $(modname))),\
-D"KBUILD_MODNAME=KBUILD_STR($(call name-fix,$(modname)))")
#hash values
ifdef CONFIG_DYNAMIC_DEBUG
debug_flags = -D"DEBUG_HASH=$(shell ./scripts/basic/hash djb2 $(@D)$(modname))"\
-D"DEBUG_HASH2=$(shell ./scripts/basic/hash r5 $(@D)$(modname))"
else
debug_flags =
endif
orig_c_flags = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(KBUILD_SUBDIR_CCFLAGS) \
$(ccflags-y) $(CFLAGS_$(basetarget).o)
_c_flags = $(filter-out $(CFLAGS_REMOVE_$(basetarget).o), $(orig_c_flags))
@ -152,8 +144,7 @@ endif
c_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
$(__c_flags) $(modkern_cflags) \
-D"KBUILD_STR(s)=\#s" $(basename_flags) $(modname_flags) \
$(debug_flags)
-D"KBUILD_STR(s)=\#s" $(basename_flags) $(modname_flags)
a_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
$(__a_flags) $(modkern_aflags)

View File

@ -9,7 +9,7 @@
# fixdep: Used to generate dependency information during build process
# docproc: Used in Documentation/DocBook
hostprogs-y := fixdep docproc hash
hostprogs-y := fixdep docproc
always := $(hostprogs-y)
# fixdep is needed to compile other host programs

View File

@ -1,64 +0,0 @@
/*
* Copyright (C) 2008 Red Hat, Inc., Jason Baron <jbaron@redhat.com>
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define DYNAMIC_DEBUG_HASH_BITS 6
static const char *program;
static void usage(void)
{
printf("Usage: %s <djb2|r5> <modname>\n", program);
exit(1);
}
/* djb2 hashing algorithm by Dan Bernstein. From:
* http://www.cse.yorku.ca/~oz/hash.html
*/
static unsigned int djb2_hash(char *str)
{
unsigned long hash = 5381;
int c;
c = *str;
while (c) {
hash = ((hash << 5) + hash) + c;
c = *++str;
}
return (unsigned int)(hash & ((1 << DYNAMIC_DEBUG_HASH_BITS) - 1));
}
static unsigned int r5_hash(char *str)
{
unsigned long hash = 0;
int c;
c = *str;
while (c) {
hash = (hash + (c << 4) + (c >> 4)) * 11;
c = *++str;
}
return (unsigned int)(hash & ((1 << DYNAMIC_DEBUG_HASH_BITS) - 1));
}
int main(int argc, char *argv[])
{
program = argv[0];
if (argc != 3)
usage();
if (!strcmp(argv[1], "djb2"))
printf("%d\n", djb2_hash(argv[2]));
else if (!strcmp(argv[1], "r5"))
printf("%d\n", r5_hash(argv[2]));
else
usage();
exit(0);
}

5
scripts/gcc-goto.sh Normal file
View File

@ -0,0 +1,5 @@
#!/bin/sh
# Test for gcc 'asm goto' suport
# Copyright (C) 2010, Jason Baron <jbaron@redhat.com>
echo "int main(void) { entry: asm goto (\"\"::::entry); return 0; }" | $1 -x c - -c -o /dev/null >/dev/null 2>&1 && echo "y"