* [PATCH v3 0/2] sched/core: Cleanup leftovers in __schedule() @ 2016-03-02 11:53 Alexander Gordeev 2016-03-02 11:53 ` [PATCH v3 1/2] sched/core: Get rid of 'cpu' argument in wq_worker_sleeping() Alexander Gordeev 2016-03-02 11:53 ` [PATCH v3 2/2] sched/core: Get rid of 'cpu' local variable in __schedule() Alexander Gordeev 0 siblings, 2 replies; 6+ messages in thread From: Alexander Gordeev @ 2016-03-02 11:53 UTC (permalink / raw) To: linux-kernel; +Cc: Alexander Gordeev, Oleg Nesterov, Peter Zijlstra Changes since v2: - rebased on top of tip/sched/core Changes since v1: - cover letter BLURB added :) - forgotten Suggested-by Oleg field added to patch 1 - raw_smp_processor_id() returned instead of mistaken smp_processor_id() - kbuild excess function parameter 'cpu' description warning fixed Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Alexander Gordeev (2): sched/core: Get rid of 'cpu' argument in wq_worker_sleeping() sched/core: Get rid of 'cpu' local variable in __schedule() kernel/sched/core.c | 6 ++---- kernel/workqueue.c | 5 ++--- kernel/workqueue_internal.h | 2 +- 3 files changed, 5 insertions(+), 8 deletions(-) -- 1.8.3.1 ^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v3 1/2] sched/core: Get rid of 'cpu' argument in wq_worker_sleeping() 2016-03-02 11:53 [PATCH v3 0/2] sched/core: Cleanup leftovers in __schedule() Alexander Gordeev @ 2016-03-02 11:53 ` Alexander Gordeev 2016-03-02 12:03 ` Peter Zijlstra 2016-03-02 11:53 ` [PATCH v3 2/2] sched/core: Get rid of 'cpu' local variable in __schedule() Alexander Gordeev 1 sibling, 1 reply; 6+ messages in thread From: Alexander Gordeev @ 2016-03-02 11:53 UTC (permalink / raw) To: linux-kernel; +Cc: Alexander Gordeev, Oleg Nesterov, Peter Zijlstra Given that wq_worker_sleeping() could only be called for a CPU it is running on, we do not need passing a CPU ID as an argument. Suggested-by: Oleg Nesterov <oleg@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> --- kernel/sched/core.c | 2 +- kernel/workqueue.c | 5 ++--- kernel/workqueue_internal.h | 2 +- 3 files changed, 4 insertions(+), 5 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 423452c..735e87c 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3183,7 +3183,7 @@ static void __sched notrace __schedule(bool preempt) if (prev->flags & PF_WQ_WORKER) { struct task_struct *to_wakeup; - to_wakeup = wq_worker_sleeping(prev, cpu); + to_wakeup = wq_worker_sleeping(prev); if (to_wakeup) try_to_wake_up_local(to_wakeup); } diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 7ff5dc7..2fa8d26 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -858,7 +858,6 @@ void wq_worker_waking_up(struct task_struct *task, int cpu) /** * wq_worker_sleeping - a worker is going to sleep * @task: task going to sleep - * @cpu: CPU in question, must be the current CPU number * * This function is called during schedule() when a busy worker is * going to sleep. Worker on the same cpu can be woken up by @@ -870,7 +869,7 @@ void wq_worker_waking_up(struct task_struct *task, int cpu) * Return: * Worker task on @cpu to wake up, %NULL if none. */ -struct task_struct *wq_worker_sleeping(struct task_struct *task, int cpu) +struct task_struct *wq_worker_sleeping(struct task_struct *task) { struct worker *worker = kthread_data(task), *to_wakeup = NULL; struct worker_pool *pool; @@ -886,7 +885,7 @@ struct task_struct *wq_worker_sleeping(struct task_struct *task, int cpu) pool = worker->pool; /* this can only happen on the local cpu */ - if (WARN_ON_ONCE(cpu != raw_smp_processor_id() || pool->cpu != cpu)) + if (WARN_ON_ONCE(pool->cpu != raw_smp_processor_id())) return NULL; /* diff --git a/kernel/workqueue_internal.h b/kernel/workqueue_internal.h index 4521587..8635417 100644 --- a/kernel/workqueue_internal.h +++ b/kernel/workqueue_internal.h @@ -69,6 +69,6 @@ static inline struct worker *current_wq_worker(void) * sched/core.c and workqueue.c. */ void wq_worker_waking_up(struct task_struct *task, int cpu); -struct task_struct *wq_worker_sleeping(struct task_struct *task, int cpu); +struct task_struct *wq_worker_sleeping(struct task_struct *task); #endif /* _KERNEL_WORKQUEUE_INTERNAL_H */ -- 1.8.3.1 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v3 1/2] sched/core: Get rid of 'cpu' argument in wq_worker_sleeping() 2016-03-02 11:53 ` [PATCH v3 1/2] sched/core: Get rid of 'cpu' argument in wq_worker_sleeping() Alexander Gordeev @ 2016-03-02 12:03 ` Peter Zijlstra 2016-03-02 15:28 ` Tejun Heo 0 siblings, 1 reply; 6+ messages in thread From: Peter Zijlstra @ 2016-03-02 12:03 UTC (permalink / raw) To: Alexander Gordeev; +Cc: linux-kernel, Oleg Nesterov, Tejun Heo This really should also have been Cc'ed to TJ, doing so now. On Wed, Mar 02, 2016 at 12:53:31PM +0100, Alexander Gordeev wrote: > Given that wq_worker_sleeping() could only be called for a > CPU it is running on, we do not need passing a CPU ID as an > argument. > > Suggested-by: Oleg Nesterov <oleg@redhat.com> > Cc: Oleg Nesterov <oleg@redhat.com> > Cc: Peter Zijlstra <peterz@infradead.org> > Signed-off-by: Alexander Gordeev <agordeev@redhat.com> > --- > kernel/sched/core.c | 2 +- > kernel/workqueue.c | 5 ++--- > kernel/workqueue_internal.h | 2 +- > 3 files changed, 4 insertions(+), 5 deletions(-) > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index 423452c..735e87c 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -3183,7 +3183,7 @@ static void __sched notrace __schedule(bool preempt) > if (prev->flags & PF_WQ_WORKER) { > struct task_struct *to_wakeup; > > - to_wakeup = wq_worker_sleeping(prev, cpu); > + to_wakeup = wq_worker_sleeping(prev); > if (to_wakeup) > try_to_wake_up_local(to_wakeup); > } > diff --git a/kernel/workqueue.c b/kernel/workqueue.c > index 7ff5dc7..2fa8d26 100644 > --- a/kernel/workqueue.c > +++ b/kernel/workqueue.c > @@ -858,7 +858,6 @@ void wq_worker_waking_up(struct task_struct *task, int cpu) > /** > * wq_worker_sleeping - a worker is going to sleep > * @task: task going to sleep > - * @cpu: CPU in question, must be the current CPU number > * > * This function is called during schedule() when a busy worker is > * going to sleep. Worker on the same cpu can be woken up by > @@ -870,7 +869,7 @@ void wq_worker_waking_up(struct task_struct *task, int cpu) > * Return: > * Worker task on @cpu to wake up, %NULL if none. > */ > -struct task_struct *wq_worker_sleeping(struct task_struct *task, int cpu) > +struct task_struct *wq_worker_sleeping(struct task_struct *task) > { > struct worker *worker = kthread_data(task), *to_wakeup = NULL; > struct worker_pool *pool; > @@ -886,7 +885,7 @@ struct task_struct *wq_worker_sleeping(struct task_struct *task, int cpu) > pool = worker->pool; > > /* this can only happen on the local cpu */ > - if (WARN_ON_ONCE(cpu != raw_smp_processor_id() || pool->cpu != cpu)) > + if (WARN_ON_ONCE(pool->cpu != raw_smp_processor_id())) > return NULL; > > /* > diff --git a/kernel/workqueue_internal.h b/kernel/workqueue_internal.h > index 4521587..8635417 100644 > --- a/kernel/workqueue_internal.h > +++ b/kernel/workqueue_internal.h > @@ -69,6 +69,6 @@ static inline struct worker *current_wq_worker(void) > * sched/core.c and workqueue.c. > */ > void wq_worker_waking_up(struct task_struct *task, int cpu); > -struct task_struct *wq_worker_sleeping(struct task_struct *task, int cpu); > +struct task_struct *wq_worker_sleeping(struct task_struct *task); > > #endif /* _KERNEL_WORKQUEUE_INTERNAL_H */ > -- > 1.8.3.1 > ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v3 1/2] sched/core: Get rid of 'cpu' argument in wq_worker_sleeping() 2016-03-02 12:03 ` Peter Zijlstra @ 2016-03-02 15:28 ` Tejun Heo 0 siblings, 0 replies; 6+ messages in thread From: Tejun Heo @ 2016-03-02 15:28 UTC (permalink / raw) To: Peter Zijlstra; +Cc: Alexander Gordeev, linux-kernel, Oleg Nesterov On Wed, Mar 02, 2016 at 01:03:16PM +0100, Peter Zijlstra wrote: > > This really should also have been Cc'ed to TJ, doing so now. > > On Wed, Mar 02, 2016 at 12:53:31PM +0100, Alexander Gordeev wrote: > > Given that wq_worker_sleeping() could only be called for a > > CPU it is running on, we do not need passing a CPU ID as an > > argument. > > > > Suggested-by: Oleg Nesterov <oleg@redhat.com> > > Cc: Oleg Nesterov <oleg@redhat.com> > > Cc: Peter Zijlstra <peterz@infradead.org> > > Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> I'll route this through wq/for-4.6. Thanks. -- tejun ^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v3 2/2] sched/core: Get rid of 'cpu' local variable in __schedule() 2016-03-02 11:53 [PATCH v3 0/2] sched/core: Cleanup leftovers in __schedule() Alexander Gordeev 2016-03-02 11:53 ` [PATCH v3 1/2] sched/core: Get rid of 'cpu' argument in wq_worker_sleeping() Alexander Gordeev @ 2016-03-02 11:53 ` Alexander Gordeev 2016-03-02 12:05 ` Peter Zijlstra 1 sibling, 1 reply; 6+ messages in thread From: Alexander Gordeev @ 2016-03-02 11:53 UTC (permalink / raw) To: linux-kernel; +Cc: Alexander Gordeev, Oleg Nesterov, Peter Zijlstra This update is a continuation of commit 3223d05 ("sched/core: Remove dead statement in __schedule()") and completes the removal of a dead code with a removal of an unnecessary 'cpu' local variable - as it is only used to acquire the current runqueue. Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> --- kernel/sched/core.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 735e87c..75e62ef 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3131,10 +3131,8 @@ static void __sched notrace __schedule(bool preempt) struct task_struct *prev, *next; unsigned long *switch_count; struct rq *rq; - int cpu; - cpu = smp_processor_id(); - rq = cpu_rq(cpu); + rq = this_rq(); prev = rq->curr; /* -- 1.8.3.1 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v3 2/2] sched/core: Get rid of 'cpu' local variable in __schedule() 2016-03-02 11:53 ` [PATCH v3 2/2] sched/core: Get rid of 'cpu' local variable in __schedule() Alexander Gordeev @ 2016-03-02 12:05 ` Peter Zijlstra 0 siblings, 0 replies; 6+ messages in thread From: Peter Zijlstra @ 2016-03-02 12:05 UTC (permalink / raw) To: Alexander Gordeev; +Cc: linux-kernel, Oleg Nesterov On Wed, Mar 02, 2016 at 12:53:32PM +0100, Alexander Gordeev wrote: > This update is a continuation of commit 3223d05 ("sched/core: Please put [core] abbrev = 12 Into your .gitconfig, 7 char SHA1s are no good. If TJ acks the first, I can fix up this time, so no need to repost just yet. ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2016-03-02 15:28 UTC | newest] Thread overview: 6+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2016-03-02 11:53 [PATCH v3 0/2] sched/core: Cleanup leftovers in __schedule() Alexander Gordeev 2016-03-02 11:53 ` [PATCH v3 1/2] sched/core: Get rid of 'cpu' argument in wq_worker_sleeping() Alexander Gordeev 2016-03-02 12:03 ` Peter Zijlstra 2016-03-02 15:28 ` Tejun Heo 2016-03-02 11:53 ` [PATCH v3 2/2] sched/core: Get rid of 'cpu' local variable in __schedule() Alexander Gordeev 2016-03-02 12:05 ` Peter Zijlstra
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