From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta8.messagelabs.com (mail6.bemta8.messagelabs.com [216.82.243.55]) by kanga.kvack.org (Postfix) with ESMTP id C2BA16B0249 for ; Mon, 12 Sep 2011 05:56:32 -0400 (EDT) Subject: Re: [PATCH 03/10] mm: Add support for a filesystem to control swap files From: Peter Zijlstra Date: Mon, 12 Sep 2011 11:56:09 +0200 In-Reply-To: <20110912093058.GA3207@suse.de> References: <1315566054-17209-1-git-send-email-mgorman@suse.de> <1315566054-17209-4-git-send-email-mgorman@suse.de> <20110909130007.GA11810@infradead.org> <20110909131550.GV14369@suse.de> <20110909133611.GB8155@infradead.org> <1315818285.26517.18.camel@twins> <20110912093058.GA3207@suse.de> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Message-ID: <1315821369.26517.21.camel@twins> Mime-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Christoph Hellwig , Linux-MM , Linux-Netdev , Linux-NFS , LKML , Andrew Morton , David Miller , Trond Myklebust , Neil Brown On Mon, 2011-09-12 at 10:34 +0100, Mel Gorman wrote: > On Mon, Sep 12, 2011 at 11:04:45AM +0200, Peter Zijlstra wrote: > > On Fri, 2011-09-09 at 09:36 -0400, Christoph Hellwig wrote: > > > The equivalent of ->direct_IO should be used for both reads and write= s. > >=20 > > So the difference between DIO and swapIO is that swapIO needs the block > > map pinned in memory.. So at the very least you'll need those > > swap_{activate,deactivate} aops. The read/write-page thingies could > > indeed be shared with DIO. > >=20 >=20 > I'm travelling at the moment so it'll be later in the week when I investi= gate > properly but I agree swap_[de|a]ctivate are still necessary. NFS does not > need to pin a block map but it's still necessary for calling xs_set_memal= loc. Right.. but I think the hope was that we could replace the current swap bmap hackery with this and simplify the normal swap bits. But yeah, networked filesystems don't really bother with block maps on the client side ;-) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org