Re: [PATCH 1/2] sched: Move __task_rq_{, un}lock() to kernel/sched/sched.h

From: Peter Zijlstra
Date: Tue Feb 17 2015 - 06:26:26 EST

On Tue, Feb 17, 2015 at 12:11:16PM +0100, Peter Zijlstra wrote:
> On Tue, Feb 17, 2015 at 01:46:51PM +0300, Kirill Tkhai wrote:
> >
> > Place it in sched.h, because dl_task_timer() needs it.
> > Also remove lockdep check, which is not fit to this
> > function.
> No, that lockdep check is valid for all current sites.

Also, note that you just proved the reason we didn't have pi_lock there
wrong the other day.

As per 0f397f2c90ce ("sched/dl: Fix race in dl_task_timer()"):

"The only reason we don't strictly need ->pi_lock now is because
we're guaranteed to have p->state == TASK_RUNNING here and are
thus free of ttwu races".

And therefore we should use the full task_rq_lock() here.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at