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Date: Tue, 17 Apr 2012 08:23:50 -0700
From: Tejun Heo <tj@kernel.org>
To: Alexander Nikiforov <a.nikiforov@samsung.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>, Hugh Dickins <hughd@google.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
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Subject: Re: [RFD] Merge task counter into memcg
Message-ID: <20120417152350.GC32402@google.com>
References: <20120411185715.GA4317@somewhere.redhat.com>
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 <20120417010902.GA14646@somewhere.redhat.com>
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Hello,

On Tue, Apr 17, 2012 at 10:45:05AM +0400, Alexander Nikiforov wrote:
> between them. Now we have only 1 way to get notification about tasks
> file - inotify(), but this approach works only if you work from
> userspace with file (e.g. create struct file, for example with echo
> $$ /sys/abc/tasks), but when something happens from kernel side
> (do_fork()/do_exit) we cannot get any event about group of the
> process (we can scan tasks file and count number of PID, or work
> with
> waitpid(), but IMHO this is ugly solutions)

Wouldn't simply generating FS_MODIFY event on the tasks file do the
trick?

Thanks.

-- 
tejun