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Date: Wed, 7 Sep 2011 15:53:32 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Vasiliy Kulikov <segoon@openwall.com>, Tejun Heo <tj@kernel.org>,
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        Alexey Dobriyan <adobriyan@gmail.com>,
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        Pavel Emelyanov <xemul@parallels.com>
Subject: Re: [patch 2/2] fs, proc: Introduce the /proc/<pid>/map_files/
 directory v6
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On Thu, 8 Sep 2011 02:42:34 +0400
Cyrill Gorcunov <gorcunov@gmail.com> wrote:

> > > +err:
> > > +		up_read(&mm->mmap_sem);
> > > +
> > > +		for (i = 0; i < used && !ret; i++) {
> > 
> > The "&& !ret" is unneeded?
> 
> No, it's needed, since it makes sure that if "impossible"
> scenario happens and flex-arrays fails with preallocated
> data so we will reach this point with used > 0 and ret = -ENOMEM
> and thus will not call for proc_map_files_instantiate as needed.

Well, it doesn't need to be tested on each pass around the loop - that's
misleading and inefficient (unless the compiler is being particularly clever).