Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2993265AbXEBOio (ORCPT ); Wed, 2 May 2007 10:38:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S2993266AbXEBOin (ORCPT ); Wed, 2 May 2007 10:38:43 -0400 Received: from mail.gmx.net ([213.165.64.20]:37356 "HELO mail.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S2993265AbXEBOin (ORCPT ); Wed, 2 May 2007 10:38:43 -0400 X-Authenticated: #5039886 X-Provags-ID: V01U2FsdGVkX1+GQRFAxP2GtcAlrUV0x3lP4/lSYKhYD3TMyjcXPD a72gnb+xU/CnXx Date: Wed, 2 May 2007 16:38:39 +0200 From: =?iso-8859-1?Q?Bj=F6rn?= Steinbrink To: Hugh Dickins Cc: Phillip Susi , Linux-kernel Subject: Re: Execute in place Message-ID: <20070502143839.GA31961@atjola.homenet> Mail-Followup-To: =?iso-8859-1?Q?Bj=F6rn?= Steinbrink , Hugh Dickins , Phillip Susi , Linux-kernel References: <4637B751.1080907@cfl.rr.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.13 (2006-08-11) X-Y-GMX-Trusted: 0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1325 Lines: 28 On 2007.05.02 15:04:44 +0100, Hugh Dickins wrote: > On Tue, 1 May 2007, Phillip Susi wrote: > > I seem to remember seeing some patches go by at some point that > > allowed one of the rom type embeded system filesystems to directly > > execute binaries out of the original rom memory rather than copying > > them to ram first, then executing from there. I was wondering if > > rootfs or tmpfs support such execute in place today, or if binaries > > executed from there have their code segments duplicated in ram? > > Only ext2 supports it today: see Documentation/filesystems/xip.txt As I understand it, xip avoids the page cache copy. But tmpfs already lives in the page cache (or swap), so avoiding that "copy" is impossible. But I always expected tmpfs to implicitly due its own kind of xip, i.e. that it doesn't have to store its stuff in the page cache twice. Are you saying that this isn't true? According to Documentation/filesystems/xip.txt the ramdisk driver does something similar, pushing the data into the page cache and discarding the original data. thanks, Bj?rn - 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/