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Date: Fri, 18 Sep 2015 18:02:21 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jens Axboe <axboe@fb.com>, Ingo Molnar <mingo@kernel.org>,
        Frederic Weisbecker <fweisbec@gmail.com>, Chris Mason <clm@fb.com>,
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        Neil Brown <neilb@suse.de>, Christoph Hellwig <hch@lst.de>,
        Tejun Heo <tj@kernel.org>
Subject: Re: [PATCH] fs-writeback: drop wb->list_lock during blk_finish_plug()
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On Fri, Sep 18, 2015 at 05:59:56PM +0200, Peter Zijlstra wrote:
> >  - if it's not an actual PREEMPT_ACTIVE (ie in a random place)
> 
> PREEMPT_ACTIVE is actually a recursion flag, 'random place' does not
> factor into it. That is, most 'random places' will not have
> PREEMPT_ACTIVE set.

Ah, _not_ PREEMPT_ACTIVE, its late and I can't read no moar.