Messages in this thread | | | Subject | Re: [PATCH] fs-writeback: drop wb->list_lock during blk_finish_plug() | From | Jens Axboe <> | Date | Fri, 18 Sep 2015 08:23:46 -0600 |
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On 09/18/2015 07:16 AM, Chris Mason wrote: > 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.
It makes no sense for preemption schedule to NOT unplug, the fact that it doesn't is news to me as well. It was never the intent of the unplug-on-schedule to NOT unplug for certain schedule out events, that seems like very odd behavior.
-- Jens Axboe
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