From 7df1027542c9353bef4d027cb4ab8e99f69017b7 Mon Sep 17 00:00:00 2001 From: Anton Blanchard Date: Wed, 23 Nov 2011 20:07:22 +0000 Subject: powerpc/time: Optimise decrementer_check_overflow decrementer_check_overflow is called from arch_local_irq_restore so we want to make it as light weight as possible. As such, turn decrementer_check_overflow into an inline function. To avoid a circular mess of includes, separate out the two components of struct decrementer_clock and keep the struct clock_event_device part local to time.c. The fast path improves from: arch_local_irq_restore 0: mflr r0 4: std r0,16(r1) 8: stdu r1,-112(r1) c: stb r3,578(r13) 10: cmpdi cr7,r3,0 14: beq- cr7,24 <.arch_local_irq_restore+0x24> ... 24: addi r1,r1,112 28: ld r0,16(r1) 2c: mtlr r0 30: blr to: arch_local_irq_restore 0: std r30,-16(r1) 4: ld r30,0(r2) 8: stb r3,578(r13) c: cmpdi cr7,r3,0 10: beq- cr7,6c <.arch_local_irq_restore+0x6c> ... 6c: ld r30,-16(r1) 70: blr Unfortunately we still setup a local TOC (due to -mminimal-toc). Yet another sign we should be moving to -mcmodel=medium. Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/irq.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'arch/powerpc/kernel/irq.c') diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c index 745c1e7c10fd..2ff4f5e59620 100644 --- a/arch/powerpc/kernel/irq.c +++ b/arch/powerpc/kernel/irq.c @@ -115,6 +115,15 @@ static inline notrace void set_soft_enabled(unsigned long enable) : : "r" (enable), "i" (offsetof(struct paca_struct, soft_enabled))); } +static inline notrace void decrementer_check_overflow(void) +{ + u64 now = get_tb_or_rtc(); + u64 *next_tb = &__get_cpu_var(decrementers_next_tb); + + if (now >= *next_tb) + set_dec(1); +} + notrace void arch_local_irq_restore(unsigned long en) { /* -- cgit v1.2.3