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From: "H.J. Lu" <hjl.tools@gmail.com>
To: Florian Weimer <fweimer@redhat.com>
Cc: "Carlos O'Donell" <carlos@redhat.com>,
	GNU C Library <libc-alpha@sourceware.org>
Subject: Re: [PATCH] Add getcpu
Date: Wed, 5 Dec 2018 12:07:05 -0800	[thread overview]
Message-ID: <CAMe9rOo7i_-keOooa0D+P_wzatVCdKkTRiFiJ-cxpnvi+eApuQ@mail.gmail.com> (raw)
In-Reply-To: <87va47eoge.fsf@oldenburg2.str.redhat.com>

On Wed, Dec 5, 2018 at 11:57 AM Florian Weimer <fweimer@redhat.com> wrote:
>
> * H. J. Lu:
>
> > I updated the patch with a very simple test.
>
> The simple test has a race condition unfortunately.
>
> I think we could fold the test into the existing affinity tests.

Sure, I will do that.

> The main question is whether getcpu is fast enough.  It does not perform
> a system call, but in my tests a while back, it was still rather slow.

It is fast enough for NUMA spinlock.

> The new rseq-based getcpu does not support NUMA nodes, it seems.  Maybe
> it's still possible to fix that.

That will be great.  We can take advantage it when it is available.

-- 
H.J.

  reply	other threads:[~2018-12-05 20:07 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-12-05 14:29 RFC: Add getcpu wrapper H.J. Lu
2018-12-05 15:35 ` Florian Weimer
2018-12-05 15:40   ` H.J. Lu
2018-12-05 15:48     ` Florian Weimer
2018-12-05 16:00       ` Zack Weinberg
2018-12-05 16:04         ` H.J. Lu
2018-12-05 17:33 ` Carlos O'Donell
2018-12-05 17:41   ` [PATCH] Add getcpu H.J. Lu
2018-12-05 18:13     ` H.J. Lu
2018-12-05 18:48     ` Florian Weimer
2018-12-05 19:50       ` H.J. Lu
2018-12-05 19:57         ` Florian Weimer
2018-12-05 20:07           ` H.J. Lu [this message]
2018-12-05 20:14             ` H.J. Lu
2018-12-07 12:50               ` Tulio Magno Quites Machado Filho
2018-12-07 14:49                 ` H.J. Lu
2018-12-05 20:43       ` Joseph Myers
2018-12-05 20:56         ` The future of the manual (was Re: [PATCH] Add getcpu) Zack Weinberg
2018-12-05 21:28           ` Joseph Myers
2018-12-07 13:11           ` Florian Weimer
2018-12-05 21:39         ` [PATCH] Add getcpu H.J. Lu
2018-12-05 21:45           ` Joseph Myers
2018-12-05 21:55           ` Florian Weimer
2018-12-06 20:26             ` H.J. Lu
2018-12-07 16:51               ` Florian Weimer
2018-12-07 17:01                 ` H.J. Lu
2018-12-07 17:15                   ` Florian Weimer
2018-12-07 20:29                     ` [PATCH] Don't use __typeof__ (getcpu) H.J. Lu
2018-12-07 20:38                       ` Samuel Thibault
2018-12-07 20:49                         ` H.J. Lu
2018-12-10 12:20     ` [PATCH] Add getcpu Szabolcs Nagy
2018-12-10 12:22       ` Florian Weimer

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