From patchwork Wed Mar 25 06:17:08 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Weiner X-Patchwork-Id: 6088611 Return-Path: X-Original-To: patchwork-linux-fsdevel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 0B17EBF90F for ; Wed, 25 Mar 2015 06:21:05 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 2C190200E8 for ; Wed, 25 Mar 2015 06:21:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1FD402013A for ; Wed, 25 Mar 2015 06:21:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752283AbbCYGUZ (ORCPT ); Wed, 25 Mar 2015 02:20:25 -0400 Received: from gum.cmpxchg.org ([85.214.110.215]:50852 "EHLO gum.cmpxchg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752465AbbCYGRh (ORCPT ); Wed, 25 Mar 2015 02:17:37 -0400 From: Johannes Weiner To: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Linus Torvalds , Andrew Morton , Tetsuo Handa , Huang Ying , Andrea Arcangeli , Dave Chinner , Michal Hocko , Theodore Ts'o Subject: [patch 04/12] mm: oom_kill: remove unnecessary locking in exit_oom_victim() Date: Wed, 25 Mar 2015 02:17:08 -0400 Message-Id: <1427264236-17249-5-git-send-email-hannes@cmpxchg.org> X-Mailer: git-send-email 2.3.3 In-Reply-To: <1427264236-17249-1-git-send-email-hannes@cmpxchg.org> References: <1427264236-17249-1-git-send-email-hannes@cmpxchg.org> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Disabling the OOM killer needs to exclude allocators from entering, not existing victims from exiting. Right now the only waiter is suspend code, which achieves quiescence by disabling the OOM killer. But later on we want to add waits that hold the lock instead to stop new victims from showing up. Signed-off-by: Johannes Weiner Acked-by: Michal Hocko --- mm/oom_kill.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 4b9547be9170..88aa9ba40fa5 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -437,14 +437,12 @@ void exit_oom_victim(void) { clear_thread_flag(TIF_MEMDIE); - down_read(&oom_sem); /* * There is no need to signal the lasst oom_victim if there * is nobody who cares. */ if (!atomic_dec_return(&oom_victims) && oom_killer_disabled) wake_up_all(&oom_victims_wait); - up_read(&oom_sem); } /**