Re: [PATCH v4] sched: fix incorrect wait time and wait count statistics

2015-11-09 Thread Peter Zijlstra
On Fri, Nov 06, 2015 at 06:41:43PM -0800, Joonwoo Park wrote: > On Fri, Nov 06, 2015 at 02:57:49PM +0100, Peter Zijlstra wrote: > > On Tue, Oct 27, 2015 at 09:46:53PM -0700, Joonwoo Park wrote: > > > @@ -1272,6 +1272,15 @@ void set_task_cpu(struct task_struct *p, unsigned > > > int new_cpu) > > >

Re: [PATCH v4] sched: fix incorrect wait time and wait count statistics

2015-11-06 Thread Joonwoo Park
On Fri, Nov 06, 2015 at 02:57:49PM +0100, Peter Zijlstra wrote: > On Tue, Oct 27, 2015 at 09:46:53PM -0700, Joonwoo Park wrote: > > @@ -1272,6 +1272,15 @@ void set_task_cpu(struct task_struct *p, unsigned > > int new_cpu) > > WARN_ON_ONCE(p->state != TASK_RUNNING && p->state != TASK_WAKING &&

Re: [PATCH v4] sched: fix incorrect wait time and wait count statistics

2015-11-06 Thread Peter Zijlstra
On Tue, Oct 27, 2015 at 09:46:53PM -0700, Joonwoo Park wrote: > @@ -1272,6 +1272,15 @@ void set_task_cpu(struct task_struct *p, unsigned int > new_cpu) > WARN_ON_ONCE(p->state != TASK_RUNNING && p->state != TASK_WAKING && > !p->on_rq); > > + /* > + * Migratin

[PATCH v4] sched: fix incorrect wait time and wait count statistics

2015-10-27 Thread Joonwoo Park
At present scheduler resets task's wait start timestamp when the task migrates to another rq. This misleads scheduler itself into reporting less wait time than actual by omitting time spent for waiting prior to migration and also more wait count than actual by counting migration as wait end event