Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 asm updates from Ingo Molnar:
 "The changes in this cycle were:

   - Speed up the x86 __preempt_schedule() implementation
   - Fix/improve low level asm code debug info annotations"

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Unwind-annotate thunk_32.S
  x86: Improve cmpxchg8b_emu.S
  x86: Improve cmpxchg16b_emu.S
  x86/lib/Makefile: Remove the unnecessary "+= thunk_64.o"
  x86: Speed up ___preempt_schedule*() by using THUNK helpers
This commit is contained in:
Linus Torvalds 2014-10-13 18:14:50 +02:00
commit 197fe6b0e6
7 changed files with 61 additions and 68 deletions

View file

@ -39,8 +39,6 @@ obj-y += tsc.o tsc_msr.o io_delay.o rtc.o
obj-y += pci-iommu_table.o
obj-y += resource.o
obj-$(CONFIG_PREEMPT) += preempt.o
obj-y += process.o
obj-y += i387.o xsave.o
obj-y += ptrace.o

View file

@ -1,25 +0,0 @@
#include <linux/linkage.h>
#include <asm/dwarf2.h>
#include <asm/asm.h>
#include <asm/calling.h>
ENTRY(___preempt_schedule)
CFI_STARTPROC
SAVE_ALL
call preempt_schedule
RESTORE_ALL
ret
CFI_ENDPROC
#ifdef CONFIG_CONTEXT_TRACKING
ENTRY(___preempt_schedule_context)
CFI_STARTPROC
SAVE_ALL
call preempt_schedule_context
RESTORE_ALL
ret
CFI_ENDPROC
#endif

View file

@ -38,7 +38,7 @@ endif
else
obj-y += iomap_copy_64.o
lib-y += csum-partial_64.o csum-copy_64.o csum-wrappers_64.o
lib-y += thunk_64.o clear_page_64.o copy_page_64.o
lib-y += clear_page_64.o copy_page_64.o
lib-y += memmove_64.o memset_64.o
lib-y += copy_user_64.o copy_user_nocache_64.o
lib-y += cmpxchg16b_emu.o

View file

@ -6,15 +6,8 @@
*
*/
#include <linux/linkage.h>
#include <asm/alternative-asm.h>
#include <asm/frame.h>
#include <asm/dwarf2.h>
#ifdef CONFIG_SMP
#define SEG_PREFIX %gs:
#else
#define SEG_PREFIX
#endif
#include <asm/percpu.h>
.text
@ -39,24 +32,25 @@ CFI_STARTPROC
# *atomic* on a single cpu (as provided by the this_cpu_xx class of
# macros).
#
this_cpu_cmpxchg16b_emu:
pushf
pushfq_cfi
cli
cmpq SEG_PREFIX(%rsi), %rax
jne not_same
cmpq SEG_PREFIX 8(%rsi), %rdx
jne not_same
cmpq PER_CPU_VAR((%rsi)), %rax
jne .Lnot_same
cmpq PER_CPU_VAR(8(%rsi)), %rdx
jne .Lnot_same
movq %rbx, SEG_PREFIX(%rsi)
movq %rcx, SEG_PREFIX 8(%rsi)
movq %rbx, PER_CPU_VAR((%rsi))
movq %rcx, PER_CPU_VAR(8(%rsi))
popf
CFI_REMEMBER_STATE
popfq_cfi
mov $1, %al
ret
not_same:
popf
CFI_RESTORE_STATE
.Lnot_same:
popfq_cfi
xor %al,%al
ret

View file

@ -7,11 +7,8 @@
*/
#include <linux/linkage.h>
#include <asm/alternative-asm.h>
#include <asm/frame.h>
#include <asm/dwarf2.h>
.text
/*
@ -30,27 +27,28 @@ CFI_STARTPROC
# set the whole ZF thing (caller will just compare
# eax:edx with the expected value)
#
cmpxchg8b_emu:
pushfl
pushfl_cfi
cli
cmpl (%esi), %eax
jne not_same
jne .Lnot_same
cmpl 4(%esi), %edx
jne half_same
jne .Lhalf_same
movl %ebx, (%esi)
movl %ecx, 4(%esi)
popfl
CFI_REMEMBER_STATE
popfl_cfi
ret
not_same:
CFI_RESTORE_STATE
.Lnot_same:
movl (%esi), %eax
half_same:
.Lhalf_same:
movl 4(%esi), %edx
popfl
popfl_cfi
ret
CFI_ENDPROC

View file

@ -6,25 +6,46 @@
*/
#include <linux/linkage.h>
#include <asm/asm.h>
#include <asm/dwarf2.h>
#ifdef CONFIG_TRACE_IRQFLAGS
/* put return address in eax (arg1) */
.macro thunk_ra name,func
.macro THUNK name, func, put_ret_addr_in_eax=0
.globl \name
\name:
pushl %eax
pushl %ecx
pushl %edx
CFI_STARTPROC
pushl_cfi %eax
CFI_REL_OFFSET eax, 0
pushl_cfi %ecx
CFI_REL_OFFSET ecx, 0
pushl_cfi %edx
CFI_REL_OFFSET edx, 0
.if \put_ret_addr_in_eax
/* Place EIP in the arg1 */
movl 3*4(%esp), %eax
.endif
call \func
popl %edx
popl %ecx
popl %eax
popl_cfi %edx
CFI_RESTORE edx
popl_cfi %ecx
CFI_RESTORE ecx
popl_cfi %eax
CFI_RESTORE eax
ret
CFI_ENDPROC
_ASM_NOKPROBE(\name)
.endm
thunk_ra trace_hardirqs_on_thunk,trace_hardirqs_on_caller
thunk_ra trace_hardirqs_off_thunk,trace_hardirqs_off_caller
#ifdef CONFIG_TRACE_IRQFLAGS
THUNK trace_hardirqs_on_thunk,trace_hardirqs_on_caller,1
THUNK trace_hardirqs_off_thunk,trace_hardirqs_off_caller,1
#endif
#ifdef CONFIG_PREEMPT
THUNK ___preempt_schedule, preempt_schedule
#ifdef CONFIG_CONTEXT_TRACKING
THUNK ___preempt_schedule_context, preempt_schedule_context
#endif
#endif

View file

@ -38,6 +38,13 @@
THUNK lockdep_sys_exit_thunk,lockdep_sys_exit
#endif
#ifdef CONFIG_PREEMPT
THUNK ___preempt_schedule, preempt_schedule
#ifdef CONFIG_CONTEXT_TRACKING
THUNK ___preempt_schedule_context, preempt_schedule_context
#endif
#endif
/* SAVE_ARGS below is used only for the .cfi directives it contains. */
CFI_STARTPROC
SAVE_ARGS