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Subject: Re: [RFC patch 0/5] futex: Allow lockless empty check of hashbucket
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From: Darren Hart <dvhart@linux.intel.com>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>, Ingo Molnar <mingo@kernel.org>,
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Date: Tue, 03 Dec 2013 09:59:24 -0800
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On Sun, 2013-12-01 at 13:46 -0800, Linus Torvalds wrote:
> On Sun, Dec 1, 2013 at 12:39 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> >
> > Last time I checked, private futexes were used when appropriate.
> >
> > "strace -e futex" mainly show _PRIVATE uses.
> 
> Yeah, pthread mutexes seem to do it.

Yes, the default was changed to _PRIVATE for pthreads in glibc several
years back (2007 iirc). The performance benefits were significant.

-- 
Darren Hart
Intel Open Source Technology Center
Yocto Project - Linux Kernel