From 8cbd9cc6254065c97c4bac42daa55ba1abe73a8e Mon Sep 17 00:00:00 2001 From: David Sharp Date: Tue, 13 Nov 2012 12:18:21 -0800 Subject: tracing,x86: Add a TSC trace_clock In order to promote interoperability between userspace tracers and ftrace, add a trace_clock that reports raw TSC values which will then be recorded in the ring buffer. Userspace tracers that also record TSCs are then on exactly the same time base as the kernel and events can be unambiguously interlaced. Tested: Enabled a tracepoint and the "tsc" trace_clock and saw very large timestamp values. v2: Move arch-specific bits out of generic code. v3: Rename "x86-tsc", cleanups v7: Generic arch bits in Kbuild. Google-Bug-Id: 6980623 Link: http://lkml.kernel.org/r/1352837903-32191-1-git-send-email-dhsharp@google.com Acked-by: Ingo Molnar Cc: Masami Hiramatsu Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Signed-off-by: David Sharp Signed-off-by: Steven Rostedt --- arch/powerpc/include/asm/Kbuild | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/powerpc/include/asm') diff --git a/arch/powerpc/include/asm/Kbuild b/arch/powerpc/include/asm/Kbuild index a4fe15e33c6..2d62b484b3f 100644 --- a/arch/powerpc/include/asm/Kbuild +++ b/arch/powerpc/include/asm/Kbuild @@ -2,3 +2,4 @@ generic-y += clkdev.h generic-y += rwsem.h +generic-y += trace_clock.h -- cgit v1.2.3-70-g09d2 From e3942ba04052364d3c6454103362cafd87456010 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Wed, 14 Nov 2012 00:24:25 +0100 Subject: vtime: Consolidate a bit the ctx switch code On ia64 and powerpc, vtime context switch only consists in flushing system and user pending time, plus a few arch housekeeping. Consolidate that into a generic implementation. s390 is a special case because pending user and system time accounting there is hard to dissociate. So it's keeping its own implementation. Signed-off-by: Frederic Weisbecker Reviewed-by: Steven Rostedt Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Steven Rostedt Cc: Paul Gortmaker Cc: Tony Luck Cc: Fenghua Yu Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Martin Schwidefsky Cc: Heiko Carstens --- arch/ia64/include/asm/cputime.h | 2 ++ arch/ia64/kernel/time.c | 9 +-------- arch/powerpc/include/asm/cputime.h | 2 ++ arch/powerpc/kernel/time.c | 6 ------ arch/s390/include/asm/cputime.h | 1 + kernel/sched/cputime.c | 13 +++++++++++++ 6 files changed, 19 insertions(+), 14 deletions(-) (limited to 'arch/powerpc/include/asm') diff --git a/arch/ia64/include/asm/cputime.h b/arch/ia64/include/asm/cputime.h index 3deac956d32..7fcf7f08ab0 100644 --- a/arch/ia64/include/asm/cputime.h +++ b/arch/ia64/include/asm/cputime.h @@ -103,5 +103,7 @@ static inline void cputime_to_timeval(const cputime_t ct, struct timeval *val) #define cputime64_to_clock_t(__ct) \ cputime_to_clock_t((__force cputime_t)__ct) +extern void arch_vtime_task_switch(struct task_struct *tsk); + #endif /* CONFIG_VIRT_CPU_ACCOUNTING */ #endif /* __IA64_CPUTIME_H */ diff --git a/arch/ia64/kernel/time.c b/arch/ia64/kernel/time.c index 834c78bd3b5..c9a7d2ebe08 100644 --- a/arch/ia64/kernel/time.c +++ b/arch/ia64/kernel/time.c @@ -100,18 +100,11 @@ void vtime_account_user(struct task_struct *tsk) * accumulated times to the current process, and to prepare accounting on * the next process. */ -void vtime_task_switch(struct task_struct *prev) +void arch_vtime_task_switch(struct task_struct *prev) { struct thread_info *pi = task_thread_info(prev); struct thread_info *ni = task_thread_info(current); - if (idle_task(smp_processor_id()) != prev) - vtime_account_system(prev); - else - vtime_account_idle(prev); - - vtime_account_user(prev); - pi->ac_stamp = ni->ac_stamp; ni->ac_stime = ni->ac_utime = 0; } diff --git a/arch/powerpc/include/asm/cputime.h b/arch/powerpc/include/asm/cputime.h index 487d46ff68a..483733bd06d 100644 --- a/arch/powerpc/include/asm/cputime.h +++ b/arch/powerpc/include/asm/cputime.h @@ -228,6 +228,8 @@ static inline cputime_t clock_t_to_cputime(const unsigned long clk) #define cputime64_to_clock_t(ct) cputime_to_clock_t((cputime_t)(ct)) +static inline void arch_vtime_task_switch(struct task_struct *tsk) { } + #endif /* __KERNEL__ */ #endif /* CONFIG_VIRT_CPU_ACCOUNTING */ #endif /* __POWERPC_CPUTIME_H */ diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index a667aaf8584..3486cfad4a6 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -375,12 +375,6 @@ void vtime_account_user(struct task_struct *tsk) account_user_time(tsk, utime, utimescaled); } -void vtime_task_switch(struct task_struct *prev) -{ - vtime_account(prev); - vtime_account_user(prev); -} - #else /* ! CONFIG_VIRT_CPU_ACCOUNTING */ #define calc_cputime_factors() #endif diff --git a/arch/s390/include/asm/cputime.h b/arch/s390/include/asm/cputime.h index 023d5ae2448..d2ff41370c0 100644 --- a/arch/s390/include/asm/cputime.h +++ b/arch/s390/include/asm/cputime.h @@ -14,6 +14,7 @@ #define __ARCH_HAS_VTIME_ACCOUNT +#define __ARCH_HAS_VTIME_TASK_SWITCH /* We want to use full resolution of the CPU timer: 2**-12 micro-seconds. */ diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c index c0aa1ba752e..2e8d34aac97 100644 --- a/kernel/sched/cputime.c +++ b/kernel/sched/cputime.c @@ -443,6 +443,19 @@ void vtime_account_system_irqsafe(struct task_struct *tsk) } EXPORT_SYMBOL_GPL(vtime_account_system_irqsafe); +#ifndef __ARCH_HAS_VTIME_TASK_SWITCH +void vtime_task_switch(struct task_struct *prev) +{ + if (is_idle_task(prev)) + vtime_account_idle(prev); + else + vtime_account_system(prev); + + vtime_account_user(prev); + arch_vtime_task_switch(prev); +} +#endif + /* * Archs that account the whole time spent in the idle task * (outside irq) as idle time can rely on this and just implement -- cgit v1.2.3-70-g09d2