Messages in this thread | | | Date | Wed, 7 Nov 2007 13:50:57 +0100 | From | Jens Axboe <> | Subject | Re: [PATCH] cfq: fix IOPRIO_CLASS_IDLE delays |
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On Wed, Nov 07 2007, Oleg Nesterov wrote: > On 11/06, Jens Axboe wrote: > > > > On Tue, Nov 06 2007, Oleg Nesterov wrote: > > > > > > (I guess this patch is not complete, overflow is still possible) > > > > Hmm, where would it overflow? > > What if the queue was idle long enough (no !CLASS_IDLE requests) so that > jiffies wraps into the past wrt ->last_end_request? > > IOW, perhaps something like the patch below makes some sense. Of course, > this is only a theoretical problem, I'm not sure we really need a fix.
OK I see what you mean, probably pretty much a theoretical problem only. But that doesn't mean it should be fixed, I've applied your patch. It also collects the two paths enabling the idle class timer, so I consider it a cleanup as well as it improves readability.
-- Jens Axboe
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