* [PATCH] sched: deduplicate mm checks in normalize_rt_tasks() @ 2011-04-21 13:15 Hillf Danton 2011-04-21 13:29 ` Yong Zhang 0 siblings, 1 reply; 4+ messages in thread From: Hillf Danton @ 2011-04-21 13:15 UTC (permalink / raw) To: LKML; +Cc: Ingo Molnar, Peter Zijlstra When normalizing realtime tasks, only user tasks are concerned by checking their ->mm. If the task is not realtime, the -mm is checked again, thus the overwork could be removed. Signed-off-by: Hillf Danton <dhillf@gmail.com> --- --- a/kernel/sched.c 2011-03-30 03:09:48.000000000 +0800 +++ b/kernel/sched.c 2011-04-21 20:59:28.000000000 +0800 @@ -8364,7 +8364,7 @@ void normalize_rt_tasks(void) * Renice negative nice level userspace * tasks back to 0: */ - if (TASK_NICE(p) < 0 && p->mm) + if (TASK_NICE(p) < 0) set_user_nice(p, 0); continue; } ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] sched: deduplicate mm checks in normalize_rt_tasks() 2011-04-21 13:15 [PATCH] sched: deduplicate mm checks in normalize_rt_tasks() Hillf Danton @ 2011-04-21 13:29 ` Yong Zhang 2011-04-21 13:43 ` Yong Zhang 0 siblings, 1 reply; 4+ messages in thread From: Yong Zhang @ 2011-04-21 13:29 UTC (permalink / raw) To: Hillf Danton; +Cc: LKML, Ingo Molnar, Peter Zijlstra On Thu, Apr 21, 2011 at 09:15:56PM +0800, Hillf Danton wrote: > When normalizing realtime tasks, only user tasks are concerned by > checking their ->mm. > If the task is not realtime, the -mm is checked again, thus the > overwork could be removed. > > Signed-off-by: Hillf Danton <dhillf@gmail.com> > --- > > --- a/kernel/sched.c 2011-03-30 03:09:48.000000000 +0800 > +++ b/kernel/sched.c 2011-04-21 20:59:28.000000000 +0800 > @@ -8364,7 +8364,7 @@ void normalize_rt_tasks(void) > * Renice negative nice level userspace > * tasks back to 0: > */ > - if (TASK_NICE(p) < 0 && p->mm) > + if (TASK_NICE(p) < 0) This looks good. And we can also move TASK_NICE(p) < 0 to the upper if(), like: if (!rt_task(p) && TASK_NICE(p) < 0) { set_user_nice(p, 0); continue; } to reduce one level if() to make code cleaner :) Thanks, Yong > set_user_nice(p, 0); > continue; > } > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] sched: deduplicate mm checks in normalize_rt_tasks() 2011-04-21 13:29 ` Yong Zhang @ 2011-04-21 13:43 ` Yong Zhang 2011-04-21 13:50 ` Hillf Danton 0 siblings, 1 reply; 4+ messages in thread From: Yong Zhang @ 2011-04-21 13:43 UTC (permalink / raw) To: Hillf Danton; +Cc: LKML, Ingo Molnar, Peter Zijlstra On Thu, Apr 21, 2011 at 09:29:04PM +0800, Yong Zhang wrote: > On Thu, Apr 21, 2011 at 09:15:56PM +0800, Hillf Danton wrote: > > When normalizing realtime tasks, only user tasks are concerned by > > checking their ->mm. > > If the task is not realtime, the -mm is checked again, thus the > > overwork could be removed. > > > > Signed-off-by: Hillf Danton <dhillf@gmail.com> > > --- > > > > --- a/kernel/sched.c 2011-03-30 03:09:48.000000000 +0800 > > +++ b/kernel/sched.c 2011-04-21 20:59:28.000000000 +0800 > > @@ -8364,7 +8364,7 @@ void normalize_rt_tasks(void) > > * Renice negative nice level userspace > > * tasks back to 0: > > */ > > - if (TASK_NICE(p) < 0 && p->mm) > > + if (TASK_NICE(p) < 0) > > This looks good. > > And we can also move TASK_NICE(p) < 0 to the upper if(), > like: > if (!rt_task(p) && TASK_NICE(p) < 0) { > set_user_nice(p, 0); > continue; > } > > to reduce one level if() to make code cleaner :) Damm, I'm wrong here, just ignore it. Yours is good. Reviewed-by: Yong Zhang <yong.zhang0@gmail.com> > > Thanks, > Yong > > > set_user_nice(p, 0); > > continue; > > } > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > Please read the FAQ at http://www.tux.org/lkml/ ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] sched: deduplicate mm checks in normalize_rt_tasks() 2011-04-21 13:43 ` Yong Zhang @ 2011-04-21 13:50 ` Hillf Danton 0 siblings, 0 replies; 4+ messages in thread From: Hillf Danton @ 2011-04-21 13:50 UTC (permalink / raw) To: Yong Zhang; +Cc: LKML, Ingo Molnar, Peter Zijlstra On Thu, Apr 21, 2011 at 9:43 PM, Yong Zhang <yong.zhang0@gmail.com> wrote: > On Thu, Apr 21, 2011 at 09:29:04PM +0800, Yong Zhang wrote: >> On Thu, Apr 21, 2011 at 09:15:56PM +0800, Hillf Danton wrote: >> > When normalizing realtime tasks, only user tasks are concerned by >> > checking their ->mm. >> > If the task is not realtime, the -mm is checked again, thus the >> > overwork could be removed. >> > >> > Signed-off-by: Hillf Danton <dhillf@gmail.com> >> > --- >> > >> > --- a/kernel/sched.c 2011-03-30 03:09:48.000000000 +0800 >> > +++ b/kernel/sched.c 2011-04-21 20:59:28.000000000 +0800 >> > @@ -8364,7 +8364,7 @@ void normalize_rt_tasks(void) >> > * Renice negative nice level userspace >> > * tasks back to 0: >> > */ >> > - if (TASK_NICE(p) < 0 && p->mm) >> > + if (TASK_NICE(p) < 0) >> >> This looks good. >> >> And we can also move TASK_NICE(p) < 0 to the upper if(), >> like: >> if (!rt_task(p) && TASK_NICE(p) < 0) { >> set_user_nice(p, 0); >> continue; >> } >> >> to reduce one level if() to make code cleaner :) > > Damm, I'm wrong here, just ignore it. > Hi Yong We could not be fine every time, right? thanks Hillf > Yours is good. > > Reviewed-by: Yong Zhang <yong.zhang0@gmail.com> > >> >> Thanks, >> Yong >> >> > set_user_nice(p, 0); >> > continue; >> > } >> > -- >> > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in >> > the body of a message to majordomo@vger.kernel.org >> > More majordomo info at http://vger.kernel.org/majordomo-info.html >> > Please read the FAQ at http://www.tux.org/lkml/ ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2011-04-21 13:50 UTC | newest] Thread overview: 4+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2011-04-21 13:15 [PATCH] sched: deduplicate mm checks in normalize_rt_tasks() Hillf Danton 2011-04-21 13:29 ` Yong Zhang 2011-04-21 13:43 ` Yong Zhang 2011-04-21 13:50 ` Hillf Danton
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