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Message-ID: <4df4ef0c0801120438n4a3c1cfpd3563531929a1a91@mail.gmail.com>
Date: Sat, 12 Jan 2008 15:38:41 +0300
From: "Anton Salikhmetov" <salikhmetov@gmail.com>
To: "Peter Zijlstra" <a.p.zijlstra@chello.nl>
Subject: Re: [PATCH 2/2][RFC][BUG] msync: updating ctime and mtime at syncing
Cc: linux-mm@kvack.org, jakob@unthought.net, linux-kernel@vger.kernel.org,
       Valdis.Kletnieks@vt.edu, riel@redhat.com, ksm@42.dk,
       staubach@redhat.com, jesper.juhl@gmail.com
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2008/1/12, Peter Zijlstra <a.p.zijlstra@chello.nl>:
>
> On Sat, 2008-01-12 at 10:36 +0100, Peter Zijlstra wrote:
> > On Fri, 2008-01-11 at 03:44 +0300, Anton Salikhmetov wrote:
> >
> > > +/*
> > > + * Update the ctime and mtime stamps after checking if they are to be updated.
> > > + */
> > > +void mapped_file_update_time(struct file *file)
> > > +{
> > > +   if (test_and_clear_bit(AS_MCTIME, &file->f_mapping->flags)) {
> > > +           get_file(file);
> > > +           file_update_time(file);
> > > +           fput(file);
> > > +   }
> > > +}
> > > +
> >
> > I don't think you need the get/put file stuff here, because
>
> BTW, the reason for me noticing this is that if it would be needed there
> is a race condition right there, who is to say that the file pointer
> you're deref'ing in your test condition isn't a dead one already.

So, in your opinion, is it at all needed here to play with the file reference
counter? May I drop the get_file() and fput() calls from the
sys_msync() function?

>
>
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