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Date: Fri, 18 Sep 2015 09:16:15 -0400
From: Chris Mason <clm@fb.com>
To: Linus Torvalds <torvalds@linux-foundation.org>
CC: Dave Chinner <david@fromorbit.com>, Jens Axboe <axboe@fb.com>,
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Subject: Re: [PATCH] fs-writeback: drop wb->list_lock during blk_finish_plug()
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On Thu, Sep 17, 2015 at 11:04:03PM -0700, Linus Torvalds wrote:
> On Thu, Sep 17, 2015 at 10:40 PM, Dave Chinner <david@fromorbit.com> wrote:
> >
> > Ok, makes sense - the plug is not being flushed as we switch away,
> > but Chris' patch makes it do that.
> 
> Yup.

Huh, that does make much more sense, thanks Linus.  I'm wondering where
else I've assumed that cond_resched() unplugged.

> 
> And I actually think Chris' patch is better than the one I sent out
> (but maybe the scheduler people should take a look at the behavior of
> cond_resched()), I just wanted you to test that to verify the
> behavior.

Ok, I'll fix up the description and comments and send out.

-chris