Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750856AbVKJN1n (ORCPT ); Thu, 10 Nov 2005 08:27:43 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750863AbVKJN1n (ORCPT ); Thu, 10 Nov 2005 08:27:43 -0500 Received: from taurus.voltaire.com ([193.47.165.240]:54925 "EHLO taurus.voltaire.com") by vger.kernel.org with ESMTP id S1750861AbVKJN1l (ORCPT ); Thu, 10 Nov 2005 08:27:41 -0500 Date: Thu, 10 Nov 2005 15:26:58 +0200 From: Gleb Natapov To: Hugh Dickins Cc: "Michael S. Tsirkin" , Benjamin Herrenschmidt , Petr Vandrovec , Nick Piggin , Badari Pulavarty , Linux Kernel Mailing List Subject: Re: Nick's core remove PageReserved broke vmware... Message-ID: <20051110132658.GP8942@minantech.com> References: <20051110124949.GM8942@minantech.com> <20051110131630.GF16589@mellanox.co.il> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-OriginalArrivalTime: 10 Nov 2005 13:27:40.0181 (UTC) FILETIME=[85F30C50:01C5E5FA] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1104 Lines: 29 On Thu, Nov 10, 2005 at 01:21:25PM +0000, Hugh Dickins wrote: > On Thu, 10 Nov 2005, Michael S. Tsirkin wrote: > > Quoting Gleb Natapov : > > > On Thu, Nov 10, 2005 at 02:48:53PM +0200, Michael S. Tsirkin wrote: > > > > > Also perhapse we should skip VM_SHARED VMAs? > > > > > > > > Why? > > > > > > > They will work correctly across fork(). > > > > So why would I call madvise on such a VMA? > > To avoid the overhead of forking it e.g. if it's a large nonlinear vma, > a lot of time may be wasted on copying its ptes for fork. That's one > of the reasons I came to like your DONTCOPY. > > So, it may not be useful for your particular RDMA issue, but I see no > reason to exclude VM_SHARED vmas from the madvise, and good reason to > include them. > If the scope of DONTCOPY is more broad that just RDMA then I agree. -- Gleb. - 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/