Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751573AbWCQWVm (ORCPT ); Fri, 17 Mar 2006 17:21:42 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932210AbWCQWVm (ORCPT ); Fri, 17 Mar 2006 17:21:42 -0500 Received: from smtp105.mail.mud.yahoo.com ([209.191.85.215]:43344 "HELO smtp105.mail.mud.yahoo.com") by vger.kernel.org with SMTP id S1751570AbWCQWVl (ORCPT ); Fri, 17 Mar 2006 17:21:41 -0500 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:Message-ID:Date:From:User-Agent:X-Accept-Language:MIME-Version:To:CC:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=l6wsVdIkomJ+yRbMs0xc7/bNQhjNimy3co3iEgPpCI29F975hMSpTz7RYDpLw9gSFwnCcyV/nmlouA4NisjP0CIfTuwuv4jfCbNvu+19Kv5EsrYUDS9a+HVo8s2EXJ1LMaWjF7NjZLo0S7tfrOa7T/yFc9L2rny6syKDpd0QsP8= ; Message-ID: <441B3670.5010502@yahoo.com.au> Date: Sat, 18 Mar 2006 09:21:36 +1100 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.12) Gecko/20051007 Debian/1.7.12-1 X-Accept-Language: en MIME-Version: 1.0 To: Hugh Dickins CC: Roland Dreier , Andrew Morton , "Bryan O'Sullivan" , torvalds@osdl.org, hch@infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 10 of 20] ipath - support for userspace apps using core driver References: <71644dd19420ddb07a75.1141922823@localhost.localdomain> <1141948516.10693.55.camel@serpentine.pathscale.com> <1141949262.10693.69.camel@serpentine.pathscale.com> <20060309163740.0b589ea4.akpm@osdl.org> <1142470579.6994.78.camel@localhost.localdomain> <1142475069.6994.114.camel@localhost.localdomain> <1142477579.6994.124.camel@localhost.localdomain> <20060315192813.71a5d31a.akpm@osdl.org> <1142485103.25297.13.camel@camp4.serpentine.com> <20060315213813.747b5967.akpm@osdl.org> <4419062C.6000803@yahoo.com.au> <441A04D0.3060201@yahoo.com.au> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1227 Lines: 28 [I'm not a driver or pci/dma person either, so I can't usefully answer most of your questions, I'm afraid] Hugh Dickins wrote: > Is there any chance that your split_page() work in -mm, actually addresses > precisely those places that were screwed up by universal compound pages? > So that with your split_page(), we could go back to every >0-order page > being PageCompound, without any need for __GFP_COMP. > I think it should catch most of the places [I'm sure I've missed some :(] that split up higher-order pages (which doesn't work on compound pages, I guess this was the problem). It makes like difficult for some future patch of mine if the refcounting mechanism is changed while the page is allocated (eg. like PageReserved used to do), however I think it wouldn't be too hard to instead invert the meaning of the flag and just use it in those few places that care? -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com - 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/