From 2aa44d0567ed21b47b87d68819415d48194cb923 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Thu, 23 Aug 2007 15:18:02 +0200 Subject: sched: sched_clock_idle_[sleep|wakeup]_event() construct a more or less wall-clock time out of sched_clock(), by using ACPI-idle's existing knowledge about how much time we spent idling. This allows the rq clock to work around TSC-stops-in-C2, TSC-gets-corrupted-in-C3 type of problems. ( Besides the scheduler's statistics this also benefits blktrace and printk-timestamps as well. ) Furthermore, the precise before-C2/C3-sleep and after-C2/C3-wakeup callbacks allow the scheduler to get out the most of the period where the CPU has a reliable TSC. This results in slightly more precise task statistics. the ACPI bits were acked by Len. Signed-off-by: Ingo Molnar Acked-by: Len Brown --- include/linux/sched.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index 682ef87da6e..1845b2e99a8 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1388,7 +1388,8 @@ extern void sched_exec(void); #define sched_exec() {} #endif -extern void sched_clock_unstable_event(void); +extern void sched_clock_idle_sleep_event(void); +extern void sched_clock_idle_wakeup_event(u64 delta_ns); #ifdef CONFIG_HOTPLUG_CPU extern void idle_task_exit(void); -- cgit v1.2.3