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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 99568C11F64 for ; Tue, 29 Jun 2021 02:38:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8152B61D04 for ; Tue, 29 Jun 2021 02:38:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231700AbhF2Ckd (ORCPT ); Mon, 28 Jun 2021 22:40:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:32996 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231348AbhF2Ckd (ORCPT ); Mon, 28 Jun 2021 22:40:33 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 800F761D06; Tue, 29 Jun 2021 02:38:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1624934286; bh=Hjr1fy7uYmD/F4jSMu35M3IOYZgcksEmBOjvnncbor4=; h=Date:From:To:Subject:In-Reply-To:From; b=C5POhnZ3yvJ8nfXExRzoCH6DJhoUFfkSLheTeHApcJpREL/4Tt8MS8isWtXIh5Jjv xR2aoRasXZQ0CJKcg/nBMZcTmw8KmC8/4rBnx+kRNX7fIOO4EVsWetKVMNHkQf3GXI hMzMnIZcqM3c/g32mOfV8ffmOAId5V2vOGF5N7pU= Date: Mon, 28 Jun 2021 19:38:06 -0700 From: Andrew Morton To: akpm@linux-foundation.org, duanxiongchun@bytedance.com, guro@fb.com, hannes@cmpxchg.org, linux-mm@kvack.org, mhocko@suse.com, mm-commits@vger.kernel.org, shakeelb@google.com, songmuchun@bytedance.com, torvalds@linux-foundation.org, vdavydov.dev@gmail.com Subject: [patch 091/192] mm: memcontrol: move obj_cgroup_uncharge_pages() out of css_set_lock Message-ID: <20210629023806.5Qh-u5G5E%akpm@linux-foundation.org> In-Reply-To: <20210628193256.008961950a714730751c1423@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Muchun Song Subject: mm: memcontrol: move obj_cgroup_uncharge_pages() out of css_set_lock The css_set_lock is used to guard the list of inherited objcgs. So there is no need to uncharge kernel memory under css_set_lock. Just move it out of the lock. Link: https://lkml.kernel.org/r/20210417043538.9793-8-songmuchun@bytedance.com Signed-off-by: Muchun Song Reviewed-by: Shakeel Butt Acked-by: Roman Gushchin Acked-by: Johannes Weiner Cc: Michal Hocko Cc: Vladimir Davydov Cc: Xiongchun Duan Signed-off-by: Andrew Morton --- mm/memcontrol.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/mm/memcontrol.c~mm-memcontrol-move-obj_cgroup_uncharge_pages-out-of-css_set_lock +++ a/mm/memcontrol.c @@ -289,9 +289,10 @@ static void obj_cgroup_release(struct pe WARN_ON_ONCE(nr_bytes & (PAGE_SIZE - 1)); nr_pages = nr_bytes >> PAGE_SHIFT; - spin_lock_irqsave(&css_set_lock, flags); if (nr_pages) obj_cgroup_uncharge_pages(objcg, nr_pages); + + spin_lock_irqsave(&css_set_lock, flags); list_del(&objcg->list); spin_unlock_irqrestore(&css_set_lock, flags); _