From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 4 Apr 2007 10:03:54 +1000 From: David Chinner Subject: Re: [xfs-masters] Re: [PATCH] Cleanup and kernelify shrinker registration (rc5-mm2) Message-ID: <20070404000354.GA32597093@melbourne.sgi.com> References: <1175571885.12230.473.camel@localhost.localdomain> <20070402205825.12190e52.akpm@linux-foundation.org> <1175575503.12230.484.camel@localhost.localdomain> <20070402215702.6e3782a9.akpm@linux-foundation.org> <1175579225.12230.504.camel@localhost.localdomain> <20070402230954.27840721.akpm@linux-foundation.org> <1175584705.12230.513.camel@localhost.localdomain> <20070403123706.GX32597093@melbourne.sgi.com> <20070403103627.de831e3e.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070403103627.de831e3e.akpm@linux-foundation.org> Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: David Chinner , xfs-masters@oss.sgi.com, lkml - Kernel Mailing List , linux-mm@kvack.org, reiserfs-dev@namesys.com List-ID: On Tue, Apr 03, 2007 at 10:36:27AM -0700, Andrew Morton wrote: > On Tue, 3 Apr 2007 22:37:06 +1000 David Chinner wrote: > > > On Tue, Apr 03, 2007 at 05:18:25PM +1000, Rusty Russell wrote: > > > On Mon, 2007-04-02 at 23:09 -0700, Andrew Morton wrote: > > > This is not about efficiency. When have I *ever* posted optimization > > > patches? > > > > > > This is about clarity. We have a standard convention for > > > register/unregister. And they can't fail. Either of these would be > > > sufficient to justify a change. > > > > > > Too many people doing cool new things in the kernel, not enough > > > polishing of the crap that's already there 8( > > > > > > > But I think we need to weed that crappiness out of XFS first. > > > > Can anyone else see the contradiction in these statements? > > > > XFS's "crappiness" is a register/unregister interface. The only > > reason it's being removed is because it's getting replaced with a > > nearly identical register/unregister interface. > > Nope. XFS is introducing two new typedefs, one of which is identical to > one which we already have and it has wrapper functions which do little more > than add new names for existing stuff. And the problem with that is? You haven't noticed this in the five years it's been there providing XFS with a consistent shrinker interface..... FWIW, digging back into history, Rusty's first patch basically brings use back to the same interface we had in 2.4. Here's the 2.4 version of that function: kmem_shaker_t kmem_shake_register(kmem_shake_func_t sfunc) { kmem_shaker_t shaker = kmalloc(sizeof(*shaker), GFP_KERNEL); if (!shaker) return NULL; memset(shaker, 0, sizeof(*shaker)); shaker->shrink = sfunc; register_cache(shaker); return shaker; } Cheers, Dave. -- Dave Chinner Principal Engineer SGI Australian Software Group -- 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/ . Don't email: email@kvack.org