Messages in this thread | | | Date | Wed, 13 Aug 2014 13:50:24 -0400 | From | Rik van Riel <> | Subject | Re: [PATCH RFC] time: drop do_sys_times spinlock |
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On 08/13/2014 01:40 PM, Peter Zijlstra wrote:
> So the problem with the above is the lack of fwd progress; if > there's enough clone()/exit() happening in the thread group (and > the more CPUs the more possible), we'll keep repeating.
We can fall back to taking the lock if we circle around, or if there is a writer active when we are in seqcount_read, similar to what the semaphore (ipc/sem.c) code is doing.
read_seqbegin_or_lock would do the trick... -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/
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