From: Andrew Vagin Date: Thu, 12 Jul 2012 10:14:29 +0000 (+0400) Subject: sched: Deliver sched_switch events to the current task X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=895dd92c032e1604aa0d7afaef7716e058343b67;p=GitHub%2FLineageOS%2Fandroid_kernel_samsung_universal7580.git sched: Deliver sched_switch events to the current task Otherwise they can't be filtered for a defined task: perf record -e sched:sched_switch ./foo This command doesn't report any events without this patch. I think it isn't a security concern if someone knows who will be executed next - this can already be observed by polling /proc state. By default perf is disabled for non-root users in any case. I need these events for profiling sleep times. sched_switch is used for getting callchains and sched_stat_* is used for getting time periods. These events are combined in user space, then it can be analyzed by perf tools. Signed-off-by: Andrew Vagin Signed-off-by: Peter Zijlstra Cc: Steven Rostedt Cc: Arun Sharma Link: http://lkml.kernel.org/r/1342088069-1005148-1-git-send-email-avagin@openvz.org Signed-off-by: Ingo Molnar --- diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 468bdd44c1b..ad732b56ba7 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1910,12 +1910,12 @@ static inline void prepare_task_switch(struct rq *rq, struct task_struct *prev, struct task_struct *next) { + trace_sched_switch(prev, next); sched_info_switch(prev, next); perf_event_task_sched_out(prev, next); fire_sched_out_preempt_notifiers(prev, next); prepare_lock_switch(rq, next); prepare_arch_switch(next); - trace_sched_switch(prev, next); } /**