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Message-ID: <1420856033.28767.1.camel@stgolabs.net>
Subject: Re: Preemptionirqsoff latency issue
From: Davidlohr Bueso <dave@stgolabs.net>
To: Vaibhav Shinde <v.bhav.shinde@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>, linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>, tj@kernel.org,
        Steven Rostedt <rostedt@goodmis.org>
Date: Fri, 09 Jan 2015 18:13:53 -0800
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On Fri, 2015-01-09 at 20:19 +0530, Vaibhav Shinde wrote:
> My app runs on cpu0, while other cpus looks idle; as per my
> understanding from your comment owner of the mutex is on the cpu other
> than cpu0, and which is causing wait spin on cpu0.

The thing is, cpu0 is rescheduling too often, so you're falling out of
the spinning step.

Thanks,
Davidlohr