From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Frysinger <vapier@gentoo.org>
Subject: Re: [PATCH] glibc: Remove CPU set size checking from affinity
 functions [BZ #19143]
Date: Fri, 16 Oct 2015 23:10:03 -0400
Message-ID: <20151017031003.GE28215@vapier.lan>
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To: Florian Weimer <fweimer@redhat.com>
Cc: GNU C Library <libc-alpha@sourceware.org>, cgroups@vger.kernel.org, kosaki.motohiro@gmail.com, Linux API <linux-api@vger.kernel.org>, Li Zefan <lizefan@huawei.com>


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On 16 Oct 2015 17:06, Florian Weimer wrote:
> The current situation, briefly stated, is this: glibc tries to guess the
> kernel CPU set size and rejects attempts to specify an affinity mask
> which is larger than that, but it does not work, and glibc and the
> kernel still silently accept CPU affinity masks with invalid bits,
> without returning an error.  The glibc check does not provide any value
> to applications, it just adds pointless complexity to the library.
> Therefore, I want to remove it from glibc.

checking the validty of the cpuset mask at the time of setting attributes
seems fundamentally wrong to me.  can't the cpuset change too between the
check and the actual use ?  say you have a controller that also manages
the cpus, and it has pre-initialized the attributes, and then brings up
the cpu on demand before spawning the thread.  it wouldn't be possible to
also pre-create all the attributes.

patch makes sense to me

> +	  abort ();

why does the test call abort instead of exit ?  abort writes to stderr.
-mike

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