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Date: Mon, 25 Nov 2013 10:53:23 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: NeilBrown <neilb@suse.de>
Cc: fengguang.wu@intel.com, "Li, Shaohua" <shaohua.li@intel.com>,
        LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@kernel.org>
Subject: Re: kernel BUG at drivers/md/raid5.c:693!
Message-ID: <20131125095323.GW10022@twins.programming.kicks-ass.net>
References: <20131123032205.GB20794@localhost>
 <20131125103522.6a1c1b36@notabene.brown>
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On Mon, Nov 25, 2013 at 10:35:22AM +1100, NeilBrown wrote:
> Ingo/Peter: is it considered OK to call wake_up while holding a spinlock?

Yes, very much so. Doing a wakeup isn't _that_ expensive.

> Could "sleeping spinlocks" affect this at all? (some sample stack traces are
> below).

Not entirely sure, are you referencing to -rt where me make spinlock_t
pi-mutexes?