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sched: cleanup adjusting sched_class

PATCH In review Hiroshi Shimamoto 3 participants 4 messages Sep 24, 2007

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Hiroshi Shimamoto

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#0 lore raw

PATCH 1/1 sched: cleanup adjusting sched_class

Hi Ingo and Dmitry,

I made a clean-up patch about fixing invalid sched_class use.

Dmitry, could you please review and sign it?

The adjusting sched_class is a missing part of the already existing "do not leak PI boosting priority to the child" at the sched_fork(). This patch moves the adjusting sched_class from wake_up_new_task() to sched_fork().

Signed-off-by Hiroshi Shimamoto <[email protected]>

---

kernel/sched.c +2 -5
index 6107a0c..8862761 100644
@@ -1641,6 +1641,8 @@ void sched_fork(struct task_struct *p, int clone_flags)
 	 * Make sure we do not leak PI boosting priority to the child:
 	 */
 	p->prio = current->normal_prio;
+	if (!rt_prio(p->prio))
+		p->sched_class = &fair_sched_class;
 
 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
 	if (likely(sched_info_on()))

@@ -1682,11 +1684,6 @@ void fastcall wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
 
 	p->prio = effective_prio(p);
 
-	if (rt_prio(p->prio))
-		p->sched_class = &rt_sched_class;
-	else
-		p->sched_class = &fair_sched_class;
-
 	if (!p->sched_class->task_new || !sysctl_sched_child_runs_first ||
 			(clone_flags & CLONE_VM) || task_cpu(p) != this_cpu ||
 			!current->se.on_rq) {
#1 lore raw
Quoted 3 lines · Hiroshi Shimamoto

Hi Ingo and Dmitry,

I made a clean-up patch about fixing invalid sched_class use.

thanks!

Quoted 10 lines

Dmitry, could you please review and sign it?

The adjusting sched_class is a missing part of the already existing "do not leak PI boosting priority to the child" at the sched_fork(). This patch moves the adjusting sched_class from wake_up_new_task() to sched_fork().

Signed-off-by Hiroshi Shimamoto <[email protected]>
Signed-off-by Dmitry Adamushko <[email protected]>
Signature · 2 lines
Best regards,
Dmitry Adamushko
#2 lore raw
Quoted 11 lines · Dmitry Adamushko
Quoted 3 lines · Hiroshi Shimamoto

Hi Ingo and Dmitry,

I made a clean-up patch about fixing invalid sched_class use.

thanks!

Quoted 4 lines

Dmitry, could you please review and sign it?

Quoted 8 lines
Quoted 6 lines

The adjusting sched_class is a missing part of the already existing "do not leak PI boosting priority to the child" at the sched_fork(). This patch moves the adjusting sched_class from wake_up_new_task() to sched_fork().

Signed-off-by Hiroshi Shimamoto <[email protected]>
Signed-off-by Dmitry Adamushko <[email protected]>

thanks - i've picked up Hiroshi's cleanup.

Ingo

#3 lore raw
In reply to Hiroshi Shimamoto
Quoted 11 lines · Hiroshi Shimamoto

Hi Ingo and Dmitry,

I made a clean-up patch about fixing invalid sched_class use.

Dmitry, could you please review and sign it?

The adjusting sched_class is a missing part of the already existing "do not leak PI boosting priority to the child" at the sched_fork(). This patch moves the adjusting sched_class from wake_up_new_task() to sched_fork().

thanks. Note that your cleanup also shrinks the code a bit:

   text    data     bss     dec     hex filename
  40111    4018     292   44421    ad85 sched.o.before
  40102    4018     292   44412    ad7c sched.o.after

which never hurts :)

Ingo