x86: Move thread_info into task_struct
Now that most of the thread_info users have been cleaned up, this is straightforward. Most of this code was written by Linus. Originally-from: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jann Horn <jann@thejh.net> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/a50eab40abeaec9cb9a9e3cbdeafd32190206654.1473801993.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
parent
c65eacbe29
commit
15f4eae70d
|
@ -157,6 +157,7 @@ config X86
|
|||
select SPARSE_IRQ
|
||||
select SRCU
|
||||
select SYSCTL_EXCEPTION_TRACE
|
||||
select THREAD_INFO_IN_TASK
|
||||
select USER_STACKTRACE_SUPPORT
|
||||
select VIRT_TO_BUS
|
||||
select X86_DEV_DMA_OPS if X86_64
|
||||
|
|
|
@ -179,7 +179,8 @@ GLOBAL(entry_SYSCALL_64_after_swapgs)
|
|||
* If we need to do entry work or if we guess we'll need to do
|
||||
* exit work, go straight to the slow path.
|
||||
*/
|
||||
testl $_TIF_WORK_SYSCALL_ENTRY|_TIF_ALLWORK_MASK, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
|
||||
movq PER_CPU_VAR(current_task), %r11
|
||||
testl $_TIF_WORK_SYSCALL_ENTRY|_TIF_ALLWORK_MASK, TASK_TI_flags(%r11)
|
||||
jnz entry_SYSCALL64_slow_path
|
||||
|
||||
entry_SYSCALL_64_fastpath:
|
||||
|
@ -217,7 +218,8 @@ entry_SYSCALL_64_fastpath:
|
|||
*/
|
||||
DISABLE_INTERRUPTS(CLBR_NONE)
|
||||
TRACE_IRQS_OFF
|
||||
testl $_TIF_ALLWORK_MASK, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
|
||||
movq PER_CPU_VAR(current_task), %r11
|
||||
testl $_TIF_ALLWORK_MASK, TASK_TI_flags(%r11)
|
||||
jnz 1f
|
||||
|
||||
LOCKDEP_SYS_EXIT
|
||||
|
@ -370,6 +372,7 @@ END(ptregs_\func)
|
|||
/*
|
||||
* %rdi: prev task
|
||||
* %rsi: next task
|
||||
* rsi: task we're switching to
|
||||
*/
|
||||
ENTRY(__switch_to_asm)
|
||||
/*
|
||||
|
|
|
@ -52,20 +52,6 @@ struct task_struct;
|
|||
#include <asm/cpufeature.h>
|
||||
#include <linux/atomic.h>
|
||||
|
||||
struct thread_info {
|
||||
struct task_struct *task; /* main task structure */
|
||||
__u32 flags; /* low level flags */
|
||||
__u32 cpu; /* current CPU */
|
||||
};
|
||||
|
||||
#define INIT_THREAD_INFO(tsk) \
|
||||
{ \
|
||||
.task = &tsk, \
|
||||
.flags = 0, \
|
||||
.cpu = 0, \
|
||||
}
|
||||
|
||||
#define init_thread_info (init_thread_union.thread_info)
|
||||
#define init_stack (init_thread_union.stack)
|
||||
|
||||
#else /* !__ASSEMBLY__ */
|
||||
|
@ -157,11 +143,6 @@ struct thread_info {
|
|||
*/
|
||||
#ifndef __ASSEMBLY__
|
||||
|
||||
static inline struct thread_info *current_thread_info(void)
|
||||
{
|
||||
return (struct thread_info *)(current_top_of_stack() - THREAD_SIZE);
|
||||
}
|
||||
|
||||
static inline unsigned long current_stack_pointer(void)
|
||||
{
|
||||
unsigned long sp;
|
||||
|
@ -223,33 +204,6 @@ static inline int arch_within_stack_frames(const void * const stack,
|
|||
# define cpu_current_top_of_stack (cpu_tss + TSS_sp0)
|
||||
#endif
|
||||
|
||||
/*
|
||||
* ASM operand which evaluates to a 'thread_info' address of
|
||||
* the current task, if it is known that "reg" is exactly "off"
|
||||
* bytes below the top of the stack currently.
|
||||
*
|
||||
* ( The kernel stack's size is known at build time, it is usually
|
||||
* 2 or 4 pages, and the bottom of the kernel stack contains
|
||||
* the thread_info structure. So to access the thread_info very
|
||||
* quickly from assembly code we can calculate down from the
|
||||
* top of the kernel stack to the bottom, using constant,
|
||||
* build-time calculations only. )
|
||||
*
|
||||
* For example, to fetch the current thread_info->flags value into %eax
|
||||
* on x86-64 defconfig kernels, in syscall entry code where RSP is
|
||||
* currently at exactly SIZEOF_PTREGS bytes away from the top of the
|
||||
* stack:
|
||||
*
|
||||
* mov ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS), %eax
|
||||
*
|
||||
* will translate to:
|
||||
*
|
||||
* 8b 84 24 b8 c0 ff ff mov -0x3f48(%rsp), %eax
|
||||
*
|
||||
* which is below the current RSP by almost 16K.
|
||||
*/
|
||||
#define ASM_THREAD_INFO(field, reg, off) ((field)+(off)-THREAD_SIZE)(reg)
|
||||
|
||||
#endif
|
||||
|
||||
#ifdef CONFIG_COMPAT
|
||||
|
|
|
@ -35,9 +35,7 @@ void common(void) {
|
|||
#endif
|
||||
|
||||
BLANK();
|
||||
OFFSET(TI_flags, thread_info, flags);
|
||||
|
||||
BLANK();
|
||||
OFFSET(TASK_TI_flags, task_struct, thread_info.flags);
|
||||
OFFSET(TASK_addr_limit, task_struct, thread.addr_limit);
|
||||
|
||||
BLANK();
|
||||
|
|
|
@ -40,8 +40,7 @@ static inline void stack_overflow_check(struct pt_regs *regs)
|
|||
if (user_mode(regs))
|
||||
return;
|
||||
|
||||
if (regs->sp >= curbase + sizeof(struct thread_info) +
|
||||
sizeof(struct pt_regs) + STACK_TOP_MARGIN &&
|
||||
if (regs->sp >= curbase + sizeof(struct pt_regs) + STACK_TOP_MARGIN &&
|
||||
regs->sp <= curbase + THREAD_SIZE)
|
||||
return;
|
||||
|
||||
|
|
|
@ -549,9 +549,7 @@ unsigned long get_wchan(struct task_struct *p)
|
|||
* PADDING
|
||||
* ----------- top = topmax - TOP_OF_KERNEL_STACK_PADDING
|
||||
* stack
|
||||
* ----------- bottom = start + sizeof(thread_info)
|
||||
* thread_info
|
||||
* ----------- start
|
||||
* ----------- bottom = start
|
||||
*
|
||||
* The tasks stack pointer points at the location where the
|
||||
* framepointer is stored. The data on the stack is:
|
||||
|
@ -562,7 +560,7 @@ unsigned long get_wchan(struct task_struct *p)
|
|||
*/
|
||||
top = start + THREAD_SIZE - TOP_OF_KERNEL_STACK_PADDING;
|
||||
top -= 2 * sizeof(unsigned long);
|
||||
bottom = start + sizeof(struct thread_info);
|
||||
bottom = start;
|
||||
|
||||
sp = READ_ONCE(p->thread.sp);
|
||||
if (sp < bottom || sp > top)
|
||||
|
|
Loading…
Reference in New Issue