Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759691AbZKKXiM (ORCPT ); Wed, 11 Nov 2009 18:38:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759676AbZKKXiK (ORCPT ); Wed, 11 Nov 2009 18:38:10 -0500 Received: from mga02.intel.com ([134.134.136.20]:28189 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759667AbZKKXiI (ORCPT ); Wed, 11 Nov 2009 18:38:08 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.44,726,1249282800"; d="scan'208";a="466508518" Message-ID: <4AFB4AC7.1090405@intel.com> Date: Wed, 11 Nov 2009 15:37:43 -0800 From: "Kok, Auke" User-Agent: Thunderbird 2.0.0.17 (X11/20081103) MIME-Version: 1.0 To: "Frank Ch. Eigler" CC: Arjan van de Ven , Jeff Garzik , "Wu, Fengguang" , "linux-kernel@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" , Christoph Hellwig , Al Viro , "mingo@elte.hu" , Frederic Weisbecker Subject: Re: [PATCH] vfs: Add a trace point in the mark_inode_dirty function References: <20091025225342.007138f5@infradead.org> <20091111020108.GA11423@localhost> <20091110223456.01ef355f@infradead.org> <4AFA6AEF.5060306@garzik.org> <20091111081905.270a4e55@infradead.org> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1081 Lines: 25 Frank Ch. Eigler wrote: > Arjan van de Ven writes: > >> [...] ok let me rephrase that. What would a user DO with this inode >> number information, given that the filename is already passed on; >> what additional useful, not-infinitely-hard-to-get piece of >> information [...] > > Perhaps "infinitely hard" is the wrong criterion, but passing inode > numbers lets a tracepoint client track changes to the same file, even > though the file may be renamed/unlinked over time. If you already know what the file object is, sure. We're interested in the case where we have no clue what the file object actually is to begin with. Having a trace with a random inode number pop up and then disappear into thin air won't help much at all, especially if we can't map it back to something "real" on disk. in time. Auke -- 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/