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Date: Tue, 18 Sep 2012 19:36:05 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Roland McGrath <roland@hack.frob.com>
Cc: Denys Vlasenko <vda.linux@googlemail.com>, linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Amerigo Wang <amwang@redhat.com>,
        "Jonathan M. Foote" <jmfoote@cert.org>,
        Pedro Alves <palves@redhat.com>
Subject: Re: [PATCH -mm v2] coredump: extend core dump note section to
	contain file names of mapped files
Message-ID: <20120918173605.GA27653@redhat.com>
References: <1347980129-1510-1-git-send-email-vda.linux@googlemail.com> <20120918165819.583252C0A4@topped-with-meat.com> <20120918172720.GA26606@redhat.com>
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On 09/18, Oleg Nesterov wrote:
>
> On 09/18, Roland McGrath wrote:
> >
> > It's doubtful that rolling your own single loop actually performs better
> > than just calling strlen and memcpy.

Ah, I misread your message, sorry...

> This is needed to advance 'name' if d_path() fails with !ENAMETOOLONG.
> Probably needs a comment.
>
> Or perhaps 'filename = ""' case can handle this case itself. In this
> case we do not even need strlen(), remaining = name - filename.

Yes, but you strlen + memcpy as you suggested will work too.

Oleg.