From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <sourceware-bugzilla@sourceware.org>
Received: by sourceware.org (Postfix, from userid 48)
 id E8B1F3858C27; Tue,  8 Feb 2022 22:24:49 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org E8B1F3858C27
From: "cvs-commit at gcc dot gnu.org" <sourceware-bugzilla@sourceware.org>
To: glibc-bugs@sourceware.org
Subject: [Bug libc/28865] linux: _SC_NPROCESSORS_CONF and
 _SC_NPROCESSORS_ONLN are inaccurate without /sys and /proc
Date: Tue, 08 Feb 2022 22:24:49 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: glibc
X-Bugzilla-Component: libc
X-Bugzilla-Version: 2.35
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: cvs-commit at gcc dot gnu.org
X-Bugzilla-Status: NEW
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P2
X-Bugzilla-Assigned-To: unassigned at sourceware dot org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags: security-
X-Bugzilla-Changed-Fields: 
Message-ID: <bug-28865-131-R27Qm2k7aV@http.sourceware.org/bugzilla/>
In-Reply-To: <bug-28865-131@http.sourceware.org/bugzilla/>
References: <bug-28865-131@http.sourceware.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://sourceware.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-BeenThere: glibc-bugs@sourceware.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Glibc-bugs mailing list <glibc-bugs.sourceware.org>
List-Unsubscribe: <https://sourceware.org/mailman/options/glibc-bugs>,
 <mailto:glibc-bugs-request@sourceware.org?subject=unsubscribe>
List-Archive: <https://sourceware.org/pipermail/glibc-bugs/>
List-Help: <mailto:glibc-bugs-request@sourceware.org?subject=help>
List-Subscribe: <https://sourceware.org/mailman/listinfo/glibc-bugs>,
 <mailto:glibc-bugs-request@sourceware.org?subject=subscribe>
X-List-Received-Date: Tue, 08 Feb 2022 22:24:50 -0000

https://sourceware.org/bugzilla/show_bug.cgi?id=3D28865

--- Comment #1 from cvs-commit at gcc dot gnu.org <cvs-commit at gcc dot gn=
u.org> ---
The master branch has been updated by Dmitry Levin <ldv@sourceware.org>:

https://sourceware.org/git/gitweb.cgi?p=3Dglibc.git;h=3De1d32b836410767270a=
3adf1f82b1a47e6e4cd51

commit e1d32b836410767270a3adf1f82b1a47e6e4cd51
Author: Dmitry V. Levin <ldv@altlinux.org>
Date:   Sat Feb 5 08:00:00 2022 +0000

    linux: fix accuracy of get_nprocs and get_nprocs_conf [BZ #28865]

    get_nprocs() and get_nprocs_conf() use various methods to obtain an
    accurate number of processors.  Re-introduce __get_nprocs_sched() as
    a source of information, and fix the order in which these methods are
    used to return the most accurate information.  The primary source of
    information used in both functions remains unchanged.

    This also changes __get_nprocs_sched() error return value from 2 to 0,
    but all its users are already prepared to handle that.

    Old fallback order:
      get_nprocs:
        /sys/devices/system/cpu/online -> /proc/stat -> 2
      get_nprocs_conf:
        /sys/devices/system/cpu/ -> /proc/stat -> 2

    New fallback order:
      get_nprocs:
        /sys/devices/system/cpu/online -> /proc/stat -> sched_getaffinity -=
> 2
      get_nprocs_conf:
        /sys/devices/system/cpu/ -> /proc/stat -> sched_getaffinity -> 2

    Fixes: 342298278e ("linux: Revert the use of sched_getaffinity on
get_nproc")
    Closes: BZ #28865
    Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

--=20
You are receiving this mail because:
You are on the CC list for the bug.=