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Re: [PATCH] Add getcpu

From: Florian Weimer <fweimer at redhat dot com>
To: "H.J. Lu" <hjl dot tools at gmail dot com>
Cc: "Carlos O'Donell" <carlos at redhat dot com>, GNU C Library <libc-alpha at sourceware dot org>
Date: Wed, 05 Dec 2018 20:57:37 +0100
Subject: Re: [PATCH] Add getcpu
References: <CAMe9rOpcy16tREX8Gb0qYPXXc__Vzykj2c=M20aBOn4p0gUBGw@mail.gmail.com> <a8efebb5-fa4b-d124-a635-c91f5d05e92f@redhat.com> <CAMe9rOo8Pq24S4iGt5FEUxgwq0+ywy4dsCqdxD0tioSPGc8NJg@mail.gmail.com> <877egng68l.fsf@oldenburg2.str.redhat.com> <CAMe9rOpRm1fSa4v91C1Ec8gH4J2N48FcDP-sdfZKrEiOFkmYoA@mail.gmail.com>

* 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.

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.

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

Thanks,
Florian

Follow-Ups:
- Re: [PATCH] Add getcpu
  - From: H.J. Lu

References:
- RFC: Add getcpu wrapper
  - From: H.J. Lu
- Re: RFC: Add getcpu wrapper
  - From: Carlos O'Donell
- [PATCH] Add getcpu
  - From: H.J. Lu
- Re: [PATCH] Add getcpu
  - From: Florian Weimer
- Re: [PATCH] Add getcpu
  - From: H.J. Lu

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