From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [patch 1/2] fs: mnt_want_write speedup
Date: Thu, 2 Apr 2009 16:31:53 -0400
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Cc: Nick Piggin <npiggin@suse.de>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
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	Andrew Morton <akpm@linux-foundation.org>
To: Dave Hansen <dave@linux.vnet.ibm.com>
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On Thu, Apr 02, 2009 at 11:37:20AM -0700, Dave Hansen wrote:
> > > Page faults themselves?  Which path was that from?
> > 
> > Yes. file_update_time.
> 
> We should be able to use your mnt_clone_write() optimization separate
> from the mnt_want_write() speedup here, right?  

Does file_update_time even need a separate mnt_want_write?  It should
always be after a mnt_want_write which we need for the actual data
write.