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x86/entry: Remove unneeded need_resched() loop

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Since the enabling and disabling of IRQs within preempt_schedule_irq() is
contained in a need_resched() loop, there is no need for the outer
architecture specific loop.

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lkml.kernel.org/r/20190311224752.8337-14-valentin.schneider@arm.com
This commit is contained in:
Valentin Schneider 2019-03-11 22:47:51 +00:00 committed by Thomas Gleixner
parent 79a3aaa7b8
commit b5b447b6b4
2 changed files with 2 additions and 4 deletions
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3
arch/x86/entry/entry_32.S
View File

@ -766,13 +766,12 @@ END(ret_from_exception)
#ifdef CONFIG_PREEMPT #ifdef CONFIG_PREEMPT
ENTRY(resume_kernel) ENTRY(resume_kernel)
DISABLE_INTERRUPTS(CLBR_ANY) DISABLE_INTERRUPTS(CLBR_ANY)
.Lneed_resched:
cmpl $0, PER_CPU_VAR(__preempt_count) cmpl $0, PER_CPU_VAR(__preempt_count)
jnz restore_all_kernel jnz restore_all_kernel
testl $X86_EFLAGS_IF, PT_EFLAGS(%esp) # interrupts off (exception path) ? testl $X86_EFLAGS_IF, PT_EFLAGS(%esp) # interrupts off (exception path) ?
jz restore_all_kernel jz restore_all_kernel
call preempt_schedule_irq call preempt_schedule_irq
jmp .Lneed_resched jmp restore_all_kernel
END(resume_kernel) END(resume_kernel)
#endif #endif

3
arch/x86/entry/entry_64.S
View File

@ -645,10 +645,9 @@ retint_kernel:
/* Check if we need preemption */ /* Check if we need preemption */
btl $9, EFLAGS(%rsp) /* were interrupts off? */ btl $9, EFLAGS(%rsp) /* were interrupts off? */
jnc 1f jnc 1f
0: cmpl $0, PER_CPU_VAR(__preempt_count) cmpl $0, PER_CPU_VAR(__preempt_count)
jnz 1f jnz 1f
call preempt_schedule_irq call preempt_schedule_irq
jmp 0b
1: 1:
#endif #endif
/* /*