From patchwork Thu Jun 22 08:53:32 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qi Zheng X-Patchwork-Id: 111549 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:994d:0:b0:3d9:f83d:47d9 with SMTP id k13csp4937115vqr; Thu, 22 Jun 2023 02:32:38 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ6XamKj6VK/DhzoTPAy4PlRMkFcWlQaA8K0uaF/8WRu+Gyp9P7rYmJ1lybiT1oA72F5/cHD X-Received: by 2002:a05:6a20:3c89:b0:125:5d8e:aff9 with SMTP id b9-20020a056a203c8900b001255d8eaff9mr150955pzj.26.1687426358295; Thu, 22 Jun 2023 02:32:38 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1687426358; cv=none; d=google.com; s=arc-20160816; b=w8WHaxWuCQ4z+YNz7R5ftQwOTia0/xb8gB0ufr+MkAnGNLT2BKyhn8ncTkgLtiN5qE WELQLLECY2o+4DVdCZkOuNo/7ARyQOv3bK2QJnd1i7nr6fTpJMogvnC94Tgf6HH9gTCk kejYS/fVlkdYxJRKhDIPUfaG4SlZXONjwLcKRekiwGCKVVG/U2N6w+YqGOjodZwAS2dR ohSZ5rAc/qGst4rICCcRwfwwXI1rrOAlMWreW1PVRdThdWKtGJ+LuhCoZFkidGf/VioP AMNy+0oraV3suM04sXxtoqEn/ubJc4Pjyxhm0akOa4rM7onXJfOaQ66zYbLOC4PRSf4N z21w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=YpqAnPCFjvBxCUJyQNRij7IdVYJH6Jib7EICYqtSs4Q=; b=i+Tfa+7Xxlp3QFdSAtPab2NRuUqQph2Kq8S6v5Jh12NJTXNkUsZEDxoHL0Ve7UlfSV OD2PJZ7dS3fl4uGn7w+b5B9nNMyw+Ck0slshQtxrN2z/D6M1rpwg8i4oOHySa4uxV1js XEfWmQN4/a6arragBEXEo6oRA+j8Upva7+mx5i9eeCQYf4eR1VzirE6BHbx25I0lVmyF pCo6hV8iT/dLaaORDepCY/auMQ4tA7iBh0wCDIDr+eJdrSXRRaOaCIwvVwpr4Ngravt6 jZVBvp/h7O8XpJ3atwx8LWZgLNQHFIuhZP1mgmcH5cM3iMyqql67V2u+VbI0K9Gr+6ar oD2A== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@bytedance.com header.s=google header.b=I9WP6mv1; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=bytedance.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id l8-20020a170903244800b001ae3cb42bfdsi531809pls.634.2023.06.22.02.32.24; Thu, 22 Jun 2023 02:32:38 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@bytedance.com header.s=google header.b=I9WP6mv1; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=bytedance.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231465AbjFVJG3 (ORCPT + 99 others); Thu, 22 Jun 2023 05:06:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49532 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232071AbjFVJEt (ORCPT ); Thu, 22 Jun 2023 05:04:49 -0400 Received: from mail-pl1-x62e.google.com (mail-pl1-x62e.google.com [IPv6:2607:f8b0:4864:20::62e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F245749EC for ; Thu, 22 Jun 2023 01:58:11 -0700 (PDT) Received: by mail-pl1-x62e.google.com with SMTP id d9443c01a7336-1b5585e84b4so6829435ad.0 for ; Thu, 22 Jun 2023 01:58:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1687424252; x=1690016252; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=YpqAnPCFjvBxCUJyQNRij7IdVYJH6Jib7EICYqtSs4Q=; b=I9WP6mv1rDRCGtgaLzA9lhBXeFPAHaj8y0iyY2DOjVEWCsT2F7nfNJVwyIikm+kMao zO6QJGdxbeP+Xd2yLUuD3B5OfZQRm3B4q5mm2BLvCFNnuFgYbDreBXTpY911jw5PjLjw 5qBcX7//daeu9fw2bM5v9uWJQ3Yj963JAAdMROcF9Ug6KJW+BwPKjtr4qnEx+svXyNj4 WQtBJXjBe1rX51UFB2Mb+BbnprNNOvKWLYHk9IXF69UQEETABYtrhl0ZHyku4x/+376s ovmIBUSgYXrVJUG8L2WcJE6QBBiCJCq44tzgQbbUxJYU3EpXiLR3t2TzR3wvfdUTA7wG r7SA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1687424252; x=1690016252; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=YpqAnPCFjvBxCUJyQNRij7IdVYJH6Jib7EICYqtSs4Q=; b=T6OgOlW+FionBagX012s83edhHtAQYMvrFg+HRHXgtTNaHUITpxpTzroXVpBjP0xBK HqvZlcLmCflhxD5hzmveHDqTWEkzzs6XZtLpiUddHqW3+n26SJMdsDRFyL+G6KKoFz3/ j1gQfLtlj1bolmTGRaTcK/ZqOV1JfwGs5qqtx3qh14h1qm4TCbm1l0yw3F4YCYdv8vig YYobRIMTBxXmkOthLSCtlTRPKSckUC1k5T3SSFsbTxiDXyWK4SBXU0a3Aa9zJLJzkVQE 8Eczj9/GQukaill2yv4OrcPuqPFYOihYfjMIxi78v5lXgPEP5rekbU97BiYIdBzhapzv tXAw== X-Gm-Message-State: AC+VfDxOY8rvBwVwXtc74GP9rQ9KdExb+tujQyyfzjaMenYKiy7DPzOM u47LlO3JkKew+VW5CQGBJYC5kw== X-Received: by 2002:a17:903:32c4:b0:1b3:e352:6d88 with SMTP id i4-20020a17090332c400b001b3e3526d88mr21673124plr.6.1687424251794; Thu, 22 Jun 2023 01:57:31 -0700 (PDT) Received: from C02DW0BEMD6R.bytedance.net ([139.177.225.254]) by smtp.gmail.com with ESMTPSA id h2-20020a170902f7c200b001b549fce345sm4806971plw.230.2023.06.22.01.57.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 22 Jun 2023 01:57:31 -0700 (PDT) From: Qi Zheng To: akpm@linux-foundation.org, david@fromorbit.com, tkhai@ya.ru, vbabka@suse.cz, roman.gushchin@linux.dev, djwong@kernel.org, brauner@kernel.org, paulmck@kernel.org, tytso@mit.edu Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, dm-devel@redhat.com, linux-raid@vger.kernel.org, linux-bcache@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-nfs@vger.kernel.org, linux-xfs@vger.kernel.org, linux-btrfs@vger.kernel.org, Qi Zheng Subject: [PATCH 26/29] mm: shrinker: make count and scan in shrinker debugfs lockless Date: Thu, 22 Jun 2023 16:53:32 +0800 Message-Id: <20230622085335.77010-27-zhengqi.arch@bytedance.com> X-Mailer: git-send-email 2.24.3 (Apple Git-128) In-Reply-To: <20230622085335.77010-1-zhengqi.arch@bytedance.com> References: <20230622085335.77010-1-zhengqi.arch@bytedance.com> MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1769394781449515432?= X-GMAIL-MSGID: =?utf-8?q?1769394781449515432?= Like global and memcg slab shrink, also make count and scan operations in memory shrinker debugfs lockless. The debugfs_remove_recursive() will wait for debugfs_file_put() to return, so there is no need to call rcu_read_lock() before calling shrinker_try_get(). Signed-off-by: Qi Zheng --- mm/shrinker_debug.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/mm/shrinker_debug.c b/mm/shrinker_debug.c index 3ab53fad8876..c18fa9b6b7f0 100644 --- a/mm/shrinker_debug.c +++ b/mm/shrinker_debug.c @@ -55,8 +55,8 @@ static int shrinker_debugfs_count_show(struct seq_file *m, void *v) if (!count_per_node) return -ENOMEM; - ret = down_read_killable(&shrinker_rwsem); - if (ret) { + ret = shrinker_try_get(shrinker); + if (!ret) { kfree(count_per_node); return ret; } @@ -92,7 +92,7 @@ static int shrinker_debugfs_count_show(struct seq_file *m, void *v) } while ((memcg = mem_cgroup_iter(NULL, memcg, NULL)) != NULL); rcu_read_unlock(); - up_read(&shrinker_rwsem); + shrinker_put(shrinker); kfree(count_per_node); return ret; @@ -146,8 +146,8 @@ static ssize_t shrinker_debugfs_scan_write(struct file *file, return -EINVAL; } - ret = down_read_killable(&shrinker_rwsem); - if (ret) { + ret = shrinker_try_get(shrinker); + if (!ret) { mem_cgroup_put(memcg); return ret; } @@ -159,7 +159,7 @@ static ssize_t shrinker_debugfs_scan_write(struct file *file, shrinker->scan_objects(shrinker, &sc); - up_read(&shrinker_rwsem); + shrinker_put(shrinker); mem_cgroup_put(memcg); return size;