Date: Thu, 18 Nov 2010 08:39:04 -0500
From: Christoph Hellwig <hch@infradead.org>
To: Theodore Tso <tytso@MIT.EDU>
Cc: Nick Piggin <npiggin@kernel.dk>, Peter Zijlstra <peterz@infradead.org>,
        Michel Lespinasse <walken@google.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Hugh Dickins <hughd@google.com>, Rik van Riel <riel@redhat.com>,
        Kosaki Motohiro <kosaki.motohiro@jp.fujitsu.com>,
        Theodore Tso <tytso@google.com>, Michael Rubin <mrubin@google.com>,
        Suleiman Souhlal <suleiman@google.com>
Subject: Re: [PATCH 3/3] mlock: avoid dirtying pages and triggering writeback
Message-ID: <20101118133904.GB18834@infradead.org>
References: <1289996638-21439-1-git-send-email-walken@google.com>
 <1289996638-21439-4-git-send-email-walken@google.com>
 <20101117125756.GA5576@amd>
 <1290007734.2109.941.camel@laptop>
 <20101118054629.GA3339@amd>
 <2ADBEB7E-0EC8-4536-B556-0453A8E1D5FA@mit.edu>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <2ADBEB7E-0EC8-4536-B556-0453A8E1D5FA@mit.edu>
User-Agent: Mutt/1.5.21 (2010-09-15)
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 704
Lines: 14

On Thu, Nov 18, 2010 at 05:43:06AM -0500, Theodore Tso wrote:
> Why is it at all important that mlock() force block allocation for sparse blocks?    It's  not at all specified in the mlock() API definition that it does that.
> 
> Are there really programs that assume that mlock() == fallocate()?!?

If there are programs that do they can't predate linux 2.6.15, and only
work on btrfs/ext4/xfs/etc, but not ext2/ext3/reiserfs.  Seems rather
unlikely to me.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/