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From: Hillf Danton <dhillf@gmail.com>
To: Yong Zhang <yong.zhang0@gmail.com>
Cc: LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
	Peter Zijlstra <peterz@infradead.org>,
	Mike Galbraith <efault@gmx.de>
Subject: Re: [PATCH] sched: fix priority leakage in pick_next_highest_task_rt()
Date: Tue, 17 May 2011 22:53:22 +0800	[thread overview]
Message-ID: <BANLkTimgmam0_yg+5a58T3R_NYM6RQLakQ@mail.gmail.com> (raw)
In-Reply-To: <BANLkTim=di8pbt1CzHjHYSC0SbtgJzbmkw@mail.gmail.com>

On Tue, May 17, 2011 at 10:28 AM, Yong Zhang <yong.zhang0@gmail.com> wrote:
> On Mon, May 16, 2011 at 8:55 PM, Hillf Danton <dhillf@gmail.com> wrote:
>> When picking the second highest RT task for a given runqueue, if no
>> task found after scanning the queue of priority == idx, the next idx
>> should also be checked even in case that next is already existing, or
>> the window of priority leakage could be opened.
>
> I don't see what kind of problem you patch will fix.
> And mind explaining how priority leakage could happen?
>
Hi Yong

If no task is found after scanning the list at array->queue + idx,
what should we operate on next?
And why is the list scanned?

thanks
           Hillf

  reply	other threads:[~2011-05-17 14:53 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-05-16 12:55 [PATCH] sched: fix priority leakage in pick_next_highest_task_rt() Hillf Danton
2011-05-17  2:28 ` Yong Zhang
2011-05-17 14:53   ` Hillf Danton [this message]
2011-05-18  1:14     ` Steven Rostedt
2011-05-18  2:17       ` Yong Zhang
2011-05-18  2:07     ` Yong Zhang

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