From patchwork Sat Oct 28 12:58:20 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hou Tao X-Patchwork-Id: 10030989 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 7D03E6032C for ; Sat, 28 Oct 2017 12:54:20 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6F678283C5 for ; Sat, 28 Oct 2017 12:54:20 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 62BC928415; Sat, 28 Oct 2017 12:54:20 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 165092883B for ; Sat, 28 Oct 2017 12:54:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751263AbdJ1Mw3 (ORCPT ); Sat, 28 Oct 2017 08:52:29 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:9537 "EHLO szxga05-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751167AbdJ1Mw2 (ORCPT ); Sat, 28 Oct 2017 08:52:28 -0400 Received: from 172.30.72.59 (EHLO DGGEMS408-HUB.china.huawei.com) ([172.30.72.59]) by dggrg05-dlp.huawei.com (MOS 4.4.6-GA FastPath queued) with ESMTP id DKB13574; Sat, 28 Oct 2017 20:52:16 +0800 (CST) Received: from huawei.com (10.175.124.28) by DGGEMS408-HUB.china.huawei.com (10.3.19.208) with Microsoft SMTP Server id 14.3.361.1; Sat, 28 Oct 2017 20:52:12 +0800 From: Hou Tao To: CC: , , , , , Subject: [RFC][PATCH 1/8] epoll: remove epmutex from ep_free() & eventpoll_release_file() Date: Sat, 28 Oct 2017 20:58:20 +0800 Message-ID: <1509195507-29037-2-git-send-email-houtao1@huawei.com> X-Mailer: git-send-email 2.7.5 In-Reply-To: <1509195507-29037-1-git-send-email-houtao1@huawei.com> References: <1509195507-29037-1-git-send-email-houtao1@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.124.28] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A090203.59F47D80.0078, ss=1, re=0.000, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0, ip=0.0.0.0, so=2014-11-16 11:51:01, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 3f3003b794f3e39cdadc4bc7c612dbe2 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Remove the global epmutex from ep_free() and eventpoll_release_file(). In the later patches, we will add locks with a smaller granularity to serve the same purposes of epmutex. Signed-off-by: Hou Tao --- fs/eventpoll.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/fs/eventpoll.c b/fs/eventpoll.c index 2fabd19..26ab0c5 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -835,7 +835,6 @@ static void ep_free(struct eventpoll *ep) * anymore. The only hit might come from eventpoll_release_file() but * holding "epmutex" is sufficient here. */ - mutex_lock(&epmutex); /* * Walks through the whole tree by unregistering poll callbacks. @@ -863,7 +862,6 @@ static void ep_free(struct eventpoll *ep) } mutex_unlock(&ep->mtx); - mutex_unlock(&epmutex); mutex_destroy(&ep->mtx); free_uid(ep->user); wakeup_source_unregister(ep->ws); @@ -1013,14 +1011,12 @@ void eventpoll_release_file(struct file *file) * * Besides, ep_remove() acquires the lock, so we can't hold it here. */ - mutex_lock(&epmutex); list_for_each_entry_safe(epi, next, &file->f_ep_links, fllink) { ep = epi->ep; mutex_lock_nested(&ep->mtx, 0); ep_remove(ep, epi); mutex_unlock(&ep->mtx); } - mutex_unlock(&epmutex); } static int ep_alloc(struct eventpoll **pep)