Messages in this thread | | | Date | Wed, 15 Feb 2012 20:22:21 +0000 | From | Matthew Garrett <> | Subject | Re: [PATCH] hrtimers: Special-case zero length sleeps |
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On Wed, Feb 15, 2012 at 09:14:30PM +0100, Thomas Gleixner wrote:
> Just for the extended fun of it: The pre hrtimer implementation in > Linux put the task on sleep as well up to the next jiffies boundary, > so anything which used sleep(0) on a pre hrtimer kernel was going to > sleep. That's also the case today when high resolution timers are > disabled (compile or runtime). > > So anything which relies on sleep(0) as a fast scheduling point is and > has been broken forever.
Excellent. So the real question is what /should/ sleep(0) do - nothing, schedule or sleep for an arbitrary period of time that could be years?
-- Matthew Garrett | mjg59@srcf.ucam.org
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