Messages in this thread | | | Subject | Re: [PATCH] net: sched: dev_deactivate_many(): use msleep(1) instead of yield() to wait for outstanding qdisc_run calls | From | Ben Hutchings <> | Date | Sun, 09 Mar 2014 19:09:20 +0000 |
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On Thu, 2014-03-06 at 16:06 -0500, David Miller wrote: > From: Marc Kleine-Budde <mkl@pengutronix.de> > Date: Wed, 5 Mar 2014 00:49:47 +0100 > > > @@ -839,7 +839,7 @@ void dev_deactivate_many(struct list_head *head) > > /* Wait for outstanding qdisc_run calls. */ > > list_for_each_entry(dev, head, unreg_list) > > while (some_qdisc_is_busy(dev)) > > - yield(); > > + msleep(1) > > } > > I don't understand this. > > yield() should really _mean_ yield. > > The intent of a yield() call, like this one here, is unambiguously > that the current thread cannot do anything until some other thread > gets onto the cpu and makes forward progress. > > Therefore it should allow lower priority threads to run, not just > equal or higher priority ones.
Until when?
yield() is not a sensible operation in a preemptive multitasking system, regardless of RT.
Ben.
-- Ben Hutchings I say we take off; nuke the site from orbit. It's the only way to be sure. [unhandled content-type:application/pgp-signature] | |