From: Allison Henderson Subject: Re: [PATCH 1/1] ext4: Remove empty index blocks when punching holes Date: Tue, 06 Mar 2012 11:42:21 -0700 Message-ID: <4F565A8D.90009@linux.vnet.ibm.com> References: <1330501048-14109-1-git-send-email-achender@linux.vnet.ibm.com> <4F4DDE8D.6020203@linux.vnet.ibm.com> <20120305235430.GA12796@thunk.org> <20120306164412.GD32282@thunk.org> <4F565962.1020604@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit To: "Ted Ts'o" , Lukas Czerner , Ext4 Developers List Return-path: Received: from e9.ny.us.ibm.com ([32.97.182.139]:44267 "EHLO e9.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757774Ab2CFSmo (ORCPT ); Tue, 6 Mar 2012 13:42:44 -0500 Received: from /spool/local by e9.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 6 Mar 2012 13:42:43 -0500 Received: from d01relay03.pok.ibm.com (d01relay03.pok.ibm.com [9.56.227.235]) by d01dlp02.pok.ibm.com (Postfix) with ESMTP id 301C76E8058 for ; Tue, 6 Mar 2012 13:42:28 -0500 (EST) Received: from d01av04.pok.ibm.com (d01av04.pok.ibm.com [9.56.224.64]) by d01relay03.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q26IgSpa306194 for ; Tue, 6 Mar 2012 13:42:28 -0500 Received: from d01av04.pok.ibm.com (loopback [127.0.0.1]) by d01av04.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q26IgRLH003028 for ; Tue, 6 Mar 2012 13:42:27 -0500 In-Reply-To: <4F565962.1020604@linux.vnet.ibm.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On 03/06/2012 11:37 AM, Allison Henderson wrote: > On 03/06/2012 09:44 AM, Ted Ts'o wrote: >> On Tue, Mar 06, 2012 at 08:11:37AM +0100, Lukas Czerner wrote: >>> >>> you're right my patches solves this problem (as I wrote in the commit >>> description) just because we now use a different code paths, which do >>> not have this problem. >> >> Ok, thanks. I'll look at them before the end of this week. >> >> Just to be clear, have the problematic code paths been removed in your >> patches, or are they not just being used in the problem scenario? >> Basically, is there any other time where we might need the additional >> logic which Allison added? >> >> - Ted >> > > Hi Ted, > > I think we will be ok with out this patch if we pick up Lukas's patches. > Since the new implementation is seated inside ext4_ext_remove_space, > Lukas can take advantage of the existing code there. > > In the current solution, we are seated inside map blocks, and then call > ext4_ext_rm_leaf from there. The bug in the current solution was that we > needed to free index blocks in the path to the extent we just removed, > but ext4_ext_remove_space will do this as it walks over the tree. > > There are some things in the new implementation that Lukas and I are > looking at, but once we get it straightened out, I think it will be ok > to let this patch go. Thx! > > Allison Henderson > forgot to reply to all. Resending to keep everyone posted :)