From 0cb91a2293648507886563ccb91979cfc94d6a4b Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 26 Sep 2006 10:52:28 +0200 Subject: [PATCH] i386: Account spinlocks to the caller during profiling for !FP kernels This ports the algorithm from x86-64 (with improvements) to i386. Previously this only worked for frame pointer enabled kernels. But spinlocks have a very simple stack frame that can be manually analyzed. Do this. Signed-off-by: Andi Kleen --- arch/i386/kernel/time.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) (limited to 'arch/i386/kernel/time.c') diff --git a/arch/i386/kernel/time.c b/arch/i386/kernel/time.c index edd00f6cee3..5af802ef00b 100644 --- a/arch/i386/kernel/time.c +++ b/arch/i386/kernel/time.c @@ -130,18 +130,33 @@ static int set_rtc_mmss(unsigned long nowtime) int timer_ack; -#if defined(CONFIG_SMP) && defined(CONFIG_FRAME_POINTER) unsigned long profile_pc(struct pt_regs *regs) { unsigned long pc = instruction_pointer(regs); - if (!user_mode_vm(regs) && in_lock_functions(pc)) +#ifdef CONFIG_SMP + if (!user_mode_vm(regs) && in_lock_functions(pc)) { +#ifdef CONFIG_FRAME_POINTER return *(unsigned long *)(regs->ebp + 4); - +#else + unsigned long *sp; + if ((regs->xcs & 3) == 0) + sp = (unsigned long *)®s->esp; + else + sp = (unsigned long *)regs->esp; + /* Return address is either directly at stack pointer + or above a saved eflags. Eflags has bits 22-31 zero, + kernel addresses don't. */ + if (sp[0] >> 22) + return sp[0]; + if (sp[1] >> 22) + return sp[1]; +#endif + } +#endif return pc; } EXPORT_SYMBOL(profile_pc); -#endif /* * This is the same as the above, except we _also_ save the current -- cgit v1.2.3