From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nick Piggin Subject: Re: Btrfs for mainline Date: Mon, 5 Jan 2009 21:32:22 +1100 Message-ID: <200901052132.22620.nickpiggin@yahoo.com.au> References: <1230722935.4680.5.camel@think.oraclecorp.com> <20090103.013755.42849152.ryusuke@osrg.net> <1230925087.7538.41.camel@think.oraclecorp.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Cc: Ryusuke Konishi , akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-btrfs@vger.kernel.org To: Chris Mason Return-path: In-Reply-To: <1230925087.7538.41.camel@think.oraclecorp.com> List-ID: On Saturday 03 January 2009 06:38:07 Chris Mason wrote: > On Sat, 2009-01-03 at 01:37 +0900, Ryusuke Konishi wrote: > > Hi, > > > > On Wed, 31 Dec 2008 18:19:09 -0500, Chris Mason wrote: > > > This has only btrfs as a module and would be the fastest way to see > > > the .c files. btrfs doesn't have any changes outside of fs/Makefile > > > and fs/Kconfig > > [ ... ] > > > In addition, there seem to be well-separated reusable routines such as > > async-thread (enhanced workqueue) and extent_map. Do you intend to > > move these into lib/ or so? > > Sorry, looks like I hit send too soon that time. The async-thread code > is very self contained, and was intended for generic use. Pushing that > into lib is probably a good idea. > > The extent_map and extent_buffer code was also intended for generic use. > It needs some love and care (making it work for blocksize != pagesize) > before I'd suggest moving it out of fs/btrfs. I'm yet to be convinced it is a good idea to use extents for this. Been a long time since we visited the issue, but when you converted ext2 to use the extent mapping stuff, it actually went slower, and complexity went up a lot (IIRC possibly required allocations in the writeback path). So I think it is a fine idea to live in btrfs until it is more proven and found useful elsewhere.