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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 1B2DFC43381 for ; Wed, 13 Mar 2019 19:27:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DFAD621019 for ; Wed, 13 Mar 2019 19:27:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552505252; bh=Tc3kDq2lAPDXt+ynXqMQPMgjQUWNiuK48hTE3Gn3ubs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=zqMuz8iOZSDPDEDY3/3qCoI4W7+LboGV23Qu/C6GUIBpohQN7Zv4h0kyJQVZtQAnN B78zSzyRlhMrD+eX711CAkDCktL0hMwVCSaTvCQjhG+Hd5gLUkT8gOe/FXBO3jW5Ck 0g7GsJ5FBx+/uw76zo6nXS8HcS9NWu/DSsBtb5Yc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727889AbfCMT1a (ORCPT ); Wed, 13 Mar 2019 15:27:30 -0400 Received: from mail.kernel.org ([198.145.29.99]:44492 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727572AbfCMTOG (ORCPT ); Wed, 13 Mar 2019 15:14:06 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7CA752075C; Wed, 13 Mar 2019 19:14:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552504445; bh=Tc3kDq2lAPDXt+ynXqMQPMgjQUWNiuK48hTE3Gn3ubs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UstsVZM3seDfvlM07SuJ+0FHRP2KJWBfTaUcLxYqmpdZadueZDF22n+87wXEMLz2L 9ozR6B71Hu1Z7Bpm3oVO/eFPRuBSBDdQ9YkepfWanhIDVo7FLOC/z/Wam0Zu4t/8O8 GdaVjLxJMBE38kYsvv0X3/WzFhswrUYIsv4LrY4c= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Michal Hocko , Tejun Heo , Andrew Morton , Linus Torvalds , Sasha Levin , linux-mm@kvack.org Subject: [PATCH AUTOSEL 4.19 28/48] mm: handle lru_add_drain_all for UP properly Date: Wed, 13 Mar 2019 15:12:30 -0400 Message-Id: <20190313191250.158955-28-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190313191250.158955-1-sashal@kernel.org> References: <20190313191250.158955-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Michal Hocko [ Upstream commit 6ea183d60c469560e7b08a83c9804299e84ec9eb ] Since for_each_cpu(cpu, mask) added by commit 2d3854a37e8b767a ("cpumask: introduce new API, without changing anything") did not evaluate the mask argument if NR_CPUS == 1 due to CONFIG_SMP=n, lru_add_drain_all() is hitting WARN_ON() at __flush_work() added by commit 4d43d395fed12463 ("workqueue: Try to catch flush_work() without INIT_WORK().") by unconditionally calling flush_work() [1]. Workaround this issue by using CONFIG_SMP=n specific lru_add_drain_all implementation. There is no real need to defer the implementation to the workqueue as the draining is going to happen on the local cpu. So alias lru_add_drain_all to lru_add_drain which does all the necessary work. [akpm@linux-foundation.org: fix various build warnings] [1] https://lkml.kernel.org/r/18a30387-6aa5-6123-e67c-57579ecc3f38@roeck-us.net Link: http://lkml.kernel.org/r/20190213124334.GH4525@dhcp22.suse.cz Signed-off-by: Michal Hocko Reported-by: Guenter Roeck Debugged-by: Tetsuo Handa Cc: Tejun Heo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- mm/swap.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/mm/swap.c b/mm/swap.c index 26fc9b5f1b6c..a3fc028e338e 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -321,11 +321,6 @@ static inline void activate_page_drain(int cpu) { } -static bool need_activate_page_drain(int cpu) -{ - return false; -} - void activate_page(struct page *page) { struct zone *zone = page_zone(page); @@ -654,13 +649,15 @@ void lru_add_drain(void) put_cpu(); } +#ifdef CONFIG_SMP + +static DEFINE_PER_CPU(struct work_struct, lru_add_drain_work); + static void lru_add_drain_per_cpu(struct work_struct *dummy) { lru_add_drain(); } -static DEFINE_PER_CPU(struct work_struct, lru_add_drain_work); - /* * Doesn't need any cpu hotplug locking because we do rely on per-cpu * kworkers being shut down before our page_alloc_cpu_dead callback is @@ -703,6 +700,12 @@ void lru_add_drain_all(void) mutex_unlock(&lock); } +#else +void lru_add_drain_all(void) +{ + lru_add_drain(); +} +#endif /** * release_pages - batched put_page() -- 2.19.1