From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DEA17C04AB4 for ; Thu, 16 May 2019 08:59:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A8A202087E for ; Thu, 16 May 2019 08:59:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727168AbfEPI7I (ORCPT ); Thu, 16 May 2019 04:59:08 -0400 Received: from mx2.suse.de ([195.135.220.15]:34984 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726899AbfEPI62 (ORCPT ); Thu, 16 May 2019 04:58:28 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id D9795AF7F; Thu, 16 May 2019 08:58:26 +0000 (UTC) From: Roman Penyaev Cc: Azat Khuzhin , Roman Penyaev , Andrew Morton , Al Viro , Linus Torvalds , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 09/13] epoll: support polling from userspace for ep_remove() Date: Thu, 16 May 2019 10:58:06 +0200 Message-Id: <20190516085810.31077-10-rpenyaev@suse.de> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190516085810.31077-1-rpenyaev@suse.de> References: <20190516085810.31077-1-rpenyaev@suse.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit To: unlisted-recipients:; (no To-header on input) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On ep_remove() simply mark a user item with EPOLLREMOVE if the item was ready (i.e. has some bits set). That will prevent further user index entry creation on item ->bit reuse. Signed-off-by: Roman Penyaev Cc: Andrew Morton Cc: Al Viro Cc: Linus Torvalds Cc: linux-fsdevel@vger.kernel.org Cc: linux-kernel@vger.kernel.org diff --git a/fs/eventpoll.c b/fs/eventpoll.c index f1ffccfcca67..630f473973da 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -1025,10 +1025,14 @@ static int ep_remove(struct eventpoll *ep, struct epitem *epi) rb_erase_cached(&epi->rbn, &ep->rbr); - write_lock_irq(&ep->lock); - if (ep_is_linked(epi)) - list_del_init(&epi->rdllink); - write_unlock_irq(&ep->lock); + if (ep_polled_by_user(ep)) { + ep_remove_user_item(epi); + } else { + write_lock_irq(&ep->lock); + if (ep_is_linked(epi)) + list_del_init(&epi->rdllink); + write_unlock_irq(&ep->lock); + } wakeup_source_unregister(ep_wakeup_source(epi)); /* -- 2.21.0