Messages in this thread | | | Date | Fri, 01 Nov 2013 10:49:06 -0400 | From | Prarit Bhargava <> | Subject | Re: [PATCH -v2 -tip] fix race between stop_two_cpus and stop_cpus |
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On 11/01/2013 10:47 AM, Mel Gorman wrote: > On Fri, Nov 01, 2013 at 10:41:46AM -0400, Rik van Riel wrote: >> Subject: fix race between stop_two_cpus and stop_cpus >> >> There is a race between stop_two_cpus, and the global stop_cpus. >> >> It is possible for two CPUs to get their stopper functions queued >> "backwards" from one another, resulting in the stopper threads >> getting stuck, and the system hanging. This can happen because >> queuing up stoppers is not synchronized. >> >> This patch adds synchronization between stop_cpus (a rare operation), >> and stop_two_cpus. >> >> Signed-off-by: Rik van Riel <riel@redhat.com> >> --- >> v2: use lglock, as suggested by Peter & Mel, thanks to both of you >> for insisting on nicer code :) >> > > This is a tad more comprehensible :). Thanks! > > Acked-by: Mel Gorman <mgorman@suse.de>
I'll test for a few hours and get back to everyone by the end of the day.
P.
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