Commit-ID: 602447f95461469e20c81254c1c08be23a46fe53
Gitweb: https://git.kernel.org/tip/602447f95461469e20c81254c1c08be23a46fe53
Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
AuthorDate: Wed, 27 Feb 2019 09:53:46 +0100
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Mon, 17 Jun 2019 12:43:42 +0200
x86/percpu, x86/irq: Relax {set,get}_irq_regs()
Nadav reported that since the this_cpu_*() ops got asm-volatile
constraints on, code generation suffered for do_IRQ(), but since this
is all with IRQs disabled we can use __this_cpu_*().
smp_x86_platform_ipi 234 222 -12,+0
smp_kvm_posted_intr_ipi 74 66 -8,+0
smp_kvm_posted_intr_wakeup_ipi 86 78 -8,+0
smp_apic_timer_interrupt 292 284 -8,+0
smp_kvm_posted_intr_nested_ipi 74 66 -8,+0
do_IRQ 195 187 -8,+0
Reported-by: Nadav Amit <nadav.amit@xxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/include/asm/irq_regs.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/irq_regs.h b/arch/x86/include/asm/irq_regs.h
index 8f3bee821e6c..187ce59aea28 100644
--- a/arch/x86/include/asm/irq_regs.h
+++ b/arch/x86/include/asm/irq_regs.h
@@ -16,7 +16,7 @@ DECLARE_PER_CPU(struct pt_regs *, irq_regs);
static inline struct pt_regs *get_irq_regs(void)
{
- return this_cpu_read(irq_regs);
+ return __this_cpu_read(irq_regs);
}
static inline struct pt_regs *set_irq_regs(struct pt_regs *new_regs)
@@ -24,7 +24,7 @@ static inline struct pt_regs *set_irq_regs(struct pt_regs *new_regs)
struct pt_regs *old_regs;
old_regs = get_irq_regs();
- this_cpu_write(irq_regs, new_regs);
+ __this_cpu_write(irq_regs, new_regs);
return old_regs;
}
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