From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>
Subject: Re: [patch 2/2] fs, proc: Introduce the /proc/<pid>/map_files/
	directory v6
Date: Wed, 7 Sep 2011 15:53:32 -0700
Message-ID: <20110907155332.beda7d3d.akpm@linux-foundation.org>
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To: Cyrill Gorcunov <gorcunov-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
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On Thu, 8 Sep 2011 02:42:34 +0400
Cyrill Gorcunov <gorcunov-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> 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).