From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753025AbcIQTki (ORCPT ); Sat, 17 Sep 2016 15:40:38 -0400 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:34493 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751027AbcIQTk2 (ORCPT ); Sat, 17 Sep 2016 15:40:28 -0400 Subject: Re: [PATCH] sbitmap: don't update the allocation hint on clear after resize To: Omar Sandoval , References: <54286aca-7ce6-5138-9189-83a2dff444b1@fb.com> <29fb3ca2c78084b3548fd87c0c9a946e2b68bffc.1474139647.git.osandov@fb.com> CC: , , Alexei Starovoitov From: Jens Axboe Message-ID: <227b6d24-8500-4ec9-5999-fd83f7221b8a@fb.com> Date: Sat, 17 Sep 2016 13:39:59 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: <29fb3ca2c78084b3548fd87c0c9a946e2b68bffc.1474139647.git.osandov@fb.com> Content-Type: text/plain; charset="windows-1252"; 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Avoid that by checking > that the cleared bit is still a valid hint. No measurable performance > difference in the common case. > > Signed-off-by: Omar Sandoval > --- > Jens, > > Small tweak to patch 6 that occurred to me after I sent the series out. > Feel free to fold it in to patch 6 or apply it separately as you see > fit. No worries. I can't fold since the series was already applied, so I just added the extra patch. -- Jens Axboe