proposed smp_rendezvous change
Andriy Gapon
avg at FreeBSD.org
Fri May 13 19:05:38 UTC 2011
on 13/05/2011 20:13 Max Laier said the following:
> Disregard this ... I misread the diff. You are indeed using [2] correctly as
> the "all-clear" semaphore. I still believe, that it is safer/cleaner to do
> this spin before releasing the lock instead (see my patch).
Maybe. I consider my approach a minor optimization - that is, I think that
normally smp_rendezvous calls would be sparse enough to never require that
synchronization (as proved by the past experience). So synchroning/delaying the
master CPU at the end of smp_rendezvous would slightly hurt performance. Having
the check at the start should trigger the synchronization only when it is really
required.
--
Andriy Gapon
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