From mboxrd@z Thu Jan 1 00:00:00 1970 From: Theodore Ts'o Subject: Re: [PATCH 2/2] ext4: Wait for existing dio workers in ext4_alloc_file_blocks() Date: Mon, 15 Jun 2015 00:25:54 -0400 Message-ID: <20150615042554.GH15793@thunk.org> References: <1433833126-28575-1-git-send-email-lczerner@redhat.com> <1433833126-28575-2-git-send-email-lczerner@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-ext4@vger.kernel.org To: Lukas Czerner Return-path: Received: from imap.thunk.org ([74.207.234.97]:35210 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751525AbbFOEZy (ORCPT ); Mon, 15 Jun 2015 00:25:54 -0400 Content-Disposition: inline In-Reply-To: <1433833126-28575-2-git-send-email-lczerner@redhat.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Tue, Jun 09, 2015 at 08:58:46AM +0200, Lukas Czerner wrote: > Currently existing dio workers can jump in and potentially increase > extent tree depth while we're allocating blocks in > ext4_alloc_file_blocks(). This may cause us to underestimate the number > of credits needed for the transaction because the extent tree depth can > change after our estimation. > > Fix this by waiting for all the existing dio workers in the same way as > we do it in ext4_punch_hole. We've seen errors caused by this in xfstest > generic/299, however it's really hard to reproduce. > > Signed-off-by: Lukas Czerner Thanks, applied. - Ted