Messages in this thread | | | Date | Mon, 23 Mar 2009 17:13:58 +0100 | From | Ingo Molnar <> | Subject | Re: [patch] fix ptrace slowness |
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* Oleg Nesterov <oleg@redhat.com> wrote:
> On 03/23, Ingo Molnar wrote: > > > > There's an alternative patch > > below. Would you mind to give it a test? Chances are that it will > > make UML even faster than your fix. > > > > Ingo > > > > diff --git a/kernel/sched.c b/kernel/sched.c > > index 3e827b8..2d60f23 100644 > > --- a/kernel/sched.c > > +++ b/kernel/sched.c > > @@ -2119,7 +2119,8 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state) > > * yield - it could be a while. > > */ > > if (unlikely(on_rq)) { > > - schedule_timeout_uninterruptible(1); > > + cpu_relax(); > > + cond_resched(); > > What if the caller is a realtime task? We can spin "forever", no?
hm, yes. I sure should have noticed _that_ ;-)
Ingo
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