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Message-ID: <6599ad830710061411l3fb9368al319a80469d54946e@mail.gmail.com>
Date: Sat, 6 Oct 2007 14:11:43 -0700
From: "Paul Menage" <menage@google.com>
To: "David Rientjes" <rientjes@google.com>
Subject: Re: [PATCH] task containersv11 add tasks file interface fix for cpusets
Cc: "Paul Jackson" <pj@sgi.com>, "Andrew Morton" <akpm@linux-foundation.org>,
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On 10/6/07, David Rientjes <rientjes@google.com> wrote:
> The getting and putting of the tasks will prevent them from exiting or
> being deallocated prematurely.  But this is also a critical section that
> will need to be protected by some mutex so it doesn't race with other
> set_cpus_allowed().

Is that necessary? If some other process calls set_cpus_allowed()
concurrently with a cpuset cpus update, it's not clear that there's
any defined serialization semantics that have to be achieved, as long
as the end result is that the task's cpus_allowed are within the
cpuset's cpus_allowed.

Paul