Re: [PATCH 1/2] sched/rt: Remove a redundant condition from task_woken_rt()

Re: [PATCH 1/2] sched/rt: Remove a redundant condition from task_woken_rt()

[Steven Rostedt]

On Sat,  4 Jul 2015 15:39:22 +0800
Xunlei Pang <xlpang@126.com> wrote:

> From: Xunlei Pang <pang.xunlei@linaro.org>
> 
> p has been already queued at this point, so "!task_running(rq, p)"
> and "p->nr_cpus_allowed > 1" imply that "has_pushable_tasks(rq)" is
> true, so it can be removed.
> 

Acked-by: Steven Rostedt <rostedt@goodmis.org>

-- Steve

> Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
> ---
>  kernel/sched/rt.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
> index 0d193a24..00816ee 100644
> --- a/kernel/sched/rt.c
> +++ b/kernel/sched/rt.c
> @@ -2069,7 +2069,6 @@ static void task_woken_rt(struct rq *rq, struct task_struct *p)
>  {
>  	if (!task_running(rq, p) &&
>  	    !test_tsk_need_resched(rq->curr) &&
> -	    has_pushable_tasks(rq) &&
>  	    p->nr_cpus_allowed > 1 &&
>  	    (dl_task(rq->curr) || rt_task(rq->curr)) &&
>  	    (rq->curr->nr_cpus_allowed < 2 ||

[tip:sched/core] sched/rt: Remove a redundant condition from task_woken_rt()

[tip-bot for Xunlei Pang]

Commit-ID:  8fd373548eed815858d7b5534971bdc64b4d8d2c
Gitweb:     http://git.kernel.org/tip/8fd373548eed815858d7b5534971bdc64b4d8d2c
Author:     Xunlei Pang <pang.xunlei@linaro.org>
AuthorDate: Sat, 4 Jul 2015 15:39:22 +0800
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Mon, 3 Aug 2015 12:21:19 +0200

sched/rt: Remove a redundant condition from task_woken_rt()

'p' has been already queued at this point, so "!task_running(rq, p)"
and "p->nr_cpus_allowed > 1" imply that "has_pushable_tasks(rq)" is
true, so it can be removed.

Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Juri Lelli <juri.lelli@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1435995563-3723-1-git-send-email-xlpang@126.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 kernel/sched/rt.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 0d193a24..00816ee 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -2069,7 +2069,6 @@ static void task_woken_rt(struct rq *rq, struct task_struct *p)
 {
 	if (!task_running(rq, p) &&
 	    !test_tsk_need_resched(rq->curr) &&
-	    has_pushable_tasks(rq) &&
 	    p->nr_cpus_allowed > 1 &&
 	    (dl_task(rq->curr) || rt_task(rq->curr)) &&
 	    (rq->curr->nr_cpus_allowed < 2 ||

Re: [PATCH 2/2] sched/deadline: Remove a redundant condition from task_woken_dl()

[Steven Rostedt]

On Sat,  4 Jul 2015 15:39:23 +0800
Xunlei Pang <xlpang@126.com> wrote:

> From: Xunlei Pang <pang.xunlei@linaro.org>
> 
> p has been already queued at this point, so "!task_running(rq, p)"
> and "p->nr_cpus_allowed > 1" imply that "has_pushable_dl_tasks(rq)"
> is true, so it can be removed.

Acked-by: Steven Rostedt <rostedt@goodmis.org>

-- Steve

> 
> Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
> ---
>  kernel/sched/deadline.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
> index 0a17af35..20772ee 100644
> --- a/kernel/sched/deadline.c
> +++ b/kernel/sched/deadline.c
> @@ -1657,7 +1657,6 @@ static void task_woken_dl(struct rq *rq, struct task_struct *p)
>  {
>  	if (!task_running(rq, p) &&
>  	    !test_tsk_need_resched(rq->curr) &&
> -	    has_pushable_dl_tasks(rq) &&
>  	    p->nr_cpus_allowed > 1 &&
>  	    dl_task(rq->curr) &&
>  	    (rq->curr->nr_cpus_allowed < 2 ||

[tip:sched/core] sched/deadline: Remove a redundant condition from task_woken_dl()

[tip-bot for Xunlei Pang]

Commit-ID:  3fe33bcdd358dd8c641cf4d92c9d2d9972ca94dd
Gitweb:     http://git.kernel.org/tip/3fe33bcdd358dd8c641cf4d92c9d2d9972ca94dd
Author:     Xunlei Pang <pang.xunlei@linaro.org>
AuthorDate: Sat, 4 Jul 2015 15:39:23 +0800
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Mon, 3 Aug 2015 12:21:20 +0200

sched/deadline: Remove a redundant condition from task_woken_dl()

'p' has been already queued at this point, so "!task_running(rq, p)"
and "p->nr_cpus_allowed > 1" imply that "has_pushable_dl_tasks(rq)"
is true, so it can be removed.

Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Juri Lelli <juri.lelli@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1435995563-3723-2-git-send-email-xlpang@126.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 kernel/sched/deadline.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 0a17af35..20772ee 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -1657,7 +1657,6 @@ static void task_woken_dl(struct rq *rq, struct task_struct *p)
 {
 	if (!task_running(rq, p) &&
 	    !test_tsk_need_resched(rq->curr) &&
-	    has_pushable_dl_tasks(rq) &&
 	    p->nr_cpus_allowed > 1 &&
 	    dl_task(rq->curr) &&
 	    (rq->curr->nr_cpus_allowed < 2 ||