Date: Sun, 5 Oct 2014 15:21:19 -0400
From: Tejun Heo <tj@kernel.org>
To: Joe Lawrence <joe.lawrence@stratus.com>
Cc: linux-kernel@vger.kernel.org, paulmck@linux.vnet.ibm.com, jiri@resnulli.us,
        stable@vger.kernel.org
Subject: Re: [PATCH v2 1/2] workqueue: add quiescent state between work items
Message-ID: <20141005192119.GE8549@htj.dyndns.org>
References: <1412529862-17954-1-git-send-email-joe.lawrence@stratus.com>
 <1412529862-17954-2-git-send-email-joe.lawrence@stratus.com>
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On Sun, Oct 05, 2014 at 01:24:21PM -0400, Joe Lawrence wrote:
> Similar to the stop_machine deadlock scenario on !PREEMPT kernels
> addressed in b22ce2785d97 "workqueue: cond_resched() after processing
> each work item", kworker threads requeueing back-to-back with zero jiffy
> delay can stall RCU. The cond_resched call introduced in that fix will
> yield only iff there are other higher priority tasks to run, so force a
> quiescent RCU state between work items.
> 
> Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com>
> Link: https://lkml.kernel.org/r/20140926105227.01325697@jlaw-desktop.mno.stratus.com
> Link: https://lkml.kernel.org/r/20140929115445.40221d8e@jlaw-desktop.mno.stratus.com
> Fixes: b22ce2785d97 ("workqueue: cond_resched() after processing each work item")
> Cc: <stable@vger.kernel.org>

Applied to wq/for-3.17-fixes.  If 3.17 comes out before this gets
merged, I'll send it as for-3.18.

Thanks.

-- 
tejun
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