From patchwork Mon Jul 24 09:43:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qi Zheng X-Patchwork-Id: 13324299 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 61F4BC001B0 for ; Mon, 24 Jul 2023 10:21:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231669AbjGXKUt (ORCPT ); Mon, 24 Jul 2023 06:20:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50090 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233310AbjGXKUD (ORCPT ); Mon, 24 Jul 2023 06:20:03 -0400 Received: from mail-oo1-xc2a.google.com (mail-oo1-xc2a.google.com [IPv6:2607:f8b0:4864:20::c2a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 22F6C59DD for ; Mon, 24 Jul 2023 03:12:11 -0700 (PDT) Received: by mail-oo1-xc2a.google.com with SMTP id 006d021491bc7-5671db01ee0so486816eaf.1 for ; Mon, 24 Jul 2023 03:12:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1690193531; x=1690798331; 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=F/oK6bm2Afi7WKsfFLPLaSlUUie3UdhMRHX1z52bb4o=; b=ILfu+KKW8Zykjt0+mIrKiJwHC0m40J46U09ywGBUnNmFMH+p6bFdoqWcf5sgoC+R11 ZDAcgKHacvOkg7DIHIT9i9MLP8683fzEbcS3LXQV34y6GlIiXKccM6JwB7mF5zLYC7Rz YRxN62HJN7MVK1BvTVTnQ7odm28ohLe0e8MTH2bdpEn1YZUV8uuLt00EXSMXZqU4Rzn6 qy+UyM0nGBLxqXkPxRr+KheXMplELyaRjuQB2F2cHuwJ1qNzvJYShHdPMLgNtfnwZiVy 003fV/wsUeuC8zdGXugjAo9uSGFyssDPN7hhkrubPzmwwuDpuv+bgEtYcT/5kQwzk433 IohA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1690193531; x=1690798331; 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=F/oK6bm2Afi7WKsfFLPLaSlUUie3UdhMRHX1z52bb4o=; b=C0XP7xtQa/awD7zRbsikDd8ZMLueHR0Ve++y2BkRtanjXL0lR3aKevmj7gZldTAG2o YSX0kMi+JDhu7IVno+NradmeYMgdqjWu/yIR8NY+nHxIK3vk1FxpL992MzYHbnPKCe3a 81OifJzzY0vZfYUGV4VCN9Ix+Zi5etTkQaognWwqn9TjDfUA9HbTZ88RpYH8nres0SC8 ACAZz+QVv84XiQLVs8xkSy0d5hVuBlVk/6FUtXEvxsXfB6bWA1tJRK0VapDd+dt2oHor dCL7vqvMan6RWLj5WOOH/pZxvsrbg5GIAhYWZJjrV1/kjwMgWD5FmXVES1q2bSLM6sKg xYEw== X-Gm-Message-State: ABy/qLbTnGlnJNRZomqzq6jLVFnC0LIksgywzL/aRsVsLAbj0ddRQkAz +DTamaEejv4WBxtsN/IG7xzF2HKCjAtymAchvhY= X-Google-Smtp-Source: APBJJlFeSJXGwKM1/4Fx4M034iEieIqp39l7VwM/I3gIgSntmWk50xYbsW/3q3bB2XT8c22SamI2Bg== X-Received: by 2002:a17:902:dad2:b0:1b8:9fc4:2733 with SMTP id q18-20020a170902dad200b001b89fc42733mr12483608plx.3.1690192468770; Mon, 24 Jul 2023 02:54:28 -0700 (PDT) Received: from C02DW0BEMD6R.bytedance.net ([203.208.167.147]) by smtp.gmail.com with ESMTPSA id d5-20020a170902c18500b001bb20380bf2sm8467233pld.13.2023.07.24.02.54.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 24 Jul 2023 02:54:28 -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, steven.price@arm.com, cel@kernel.org, senozhatsky@chromium.org, yujie.liu@intel.com, gregkh@linuxfoundation.org, muchun.song@linux.dev Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org, linux-erofs@lists.ozlabs.org, linux-f2fs-devel@lists.sourceforge.net, cluster-devel@redhat.com, linux-nfs@vger.kernel.org, linux-mtd@lists.infradead.org, rcu@vger.kernel.org, netdev@vger.kernel.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-xfs@vger.kernel.org, linux-btrfs@vger.kernel.org, Qi Zheng Subject: [PATCH v2 47/47] mm: shrinker: convert shrinker_rwsem to mutex Date: Mon, 24 Jul 2023 17:43:54 +0800 Message-Id: <20230724094354.90817-48-zhengqi.arch@bytedance.com> X-Mailer: git-send-email 2.24.3 (Apple Git-128) In-Reply-To: <20230724094354.90817-1-zhengqi.arch@bytedance.com> References: <20230724094354.90817-1-zhengqi.arch@bytedance.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Now there are no readers of shrinker_rwsem, so we can simply replace it with mutex lock. Signed-off-by: Qi Zheng --- drivers/md/dm-cache-metadata.c | 2 +- fs/super.c | 2 +- mm/shrinker.c | 16 ++++++++-------- mm/shrinker_debug.c | 14 +++++++------- 4 files changed, 17 insertions(+), 17 deletions(-) diff --git a/drivers/md/dm-cache-metadata.c b/drivers/md/dm-cache-metadata.c index acffed750e3e..9e0c69958587 100644 --- a/drivers/md/dm-cache-metadata.c +++ b/drivers/md/dm-cache-metadata.c @@ -1828,7 +1828,7 @@ int dm_cache_metadata_abort(struct dm_cache_metadata *cmd) * Replacement block manager (new_bm) is created and old_bm destroyed outside of * cmd root_lock to avoid ABBA deadlock that would result (due to life-cycle of * shrinker associated with the block manager's bufio client vs cmd root_lock). - * - must take shrinker_rwsem without holding cmd->root_lock + * - must take shrinker_mutex without holding cmd->root_lock */ new_bm = dm_block_manager_create(cmd->bdev, DM_CACHE_METADATA_BLOCK_SIZE << SECTOR_SHIFT, CACHE_MAX_CONCURRENT_LOCKS); diff --git a/fs/super.c b/fs/super.c index 04643fd80886..602cf54eb7da 100644 --- a/fs/super.c +++ b/fs/super.c @@ -54,7 +54,7 @@ static char *sb_writers_name[SB_FREEZE_LEVELS] = { * One thing we have to be careful of with a per-sb shrinker is that we don't * drop the last active reference to the superblock from within the shrinker. * If that happens we could trigger unregistering the shrinker from within the - * shrinker path and that leads to deadlock on the shrinker_rwsem. Hence we + * shrinker path and that leads to deadlock on the shrinker_mutex. Hence we * take a passive reference to the superblock to avoid this from occurring. */ static unsigned long super_cache_scan(struct shrinker *shrink, diff --git a/mm/shrinker.c b/mm/shrinker.c index 90c045620fe3..5c4546d2c234 100644 --- a/mm/shrinker.c +++ b/mm/shrinker.c @@ -7,7 +7,7 @@ #include LIST_HEAD(shrinker_list); -DECLARE_RWSEM(shrinker_rwsem); +DEFINE_MUTEX(shrinker_mutex); DEFINE_SPINLOCK(shrinker_lock); #ifdef CONFIG_MEMCG @@ -80,7 +80,7 @@ int alloc_shrinker_info(struct mem_cgroup *memcg) int nid, ret = 0; int array_size = 0; - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); array_size = shrinker_unit_size(shrinker_nr_max); for_each_node(nid) { info = kvzalloc_node(sizeof(*info) + array_size, GFP_KERNEL, nid); @@ -91,7 +91,7 @@ int alloc_shrinker_info(struct mem_cgroup *memcg) goto err; rcu_assign_pointer(memcg->nodeinfo[nid]->shrinker_info, info); } - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); return ret; @@ -104,7 +104,7 @@ static struct shrinker_info *shrinker_info_protected(struct mem_cgroup *memcg, int nid) { return rcu_dereference_protected(memcg->nodeinfo[nid]->shrinker_info, - lockdep_is_held(&shrinker_rwsem)); + lockdep_is_held(&shrinker_mutex)); } static struct shrinker_info *shrinker_info_rcu(struct mem_cgroup *memcg, @@ -158,7 +158,7 @@ static int expand_shrinker_info(int new_id) int new_size, old_size = 0; struct mem_cgroup *memcg; - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); if (!root_mem_cgroup) goto out; @@ -179,7 +179,7 @@ static int expand_shrinker_info(int new_id) if (!ret) shrinker_nr_max = new_nr_max; - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); return ret; } @@ -303,7 +303,7 @@ void reparent_shrinker_deferred(struct mem_cgroup *memcg) parent = root_mem_cgroup; /* Prevent from concurrent shrinker_info expand */ - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); for_each_node(nid) { child_info = shrinker_info_protected(memcg, nid); parent_info = shrinker_info_protected(parent, nid); @@ -316,7 +316,7 @@ void reparent_shrinker_deferred(struct mem_cgroup *memcg) } } } - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); } #else static int shrinker_memcg_alloc(struct shrinker *shrinker) diff --git a/mm/shrinker_debug.c b/mm/shrinker_debug.c index badda35464c3..44b620b1919d 100644 --- a/mm/shrinker_debug.c +++ b/mm/shrinker_debug.c @@ -8,7 +8,7 @@ #include /* defined in vmscan.c */ -extern struct rw_semaphore shrinker_rwsem; +extern struct mutex shrinker_mutex; extern struct list_head shrinker_list; static DEFINE_IDA(shrinker_debugfs_ida); @@ -168,7 +168,7 @@ int shrinker_debugfs_add(struct shrinker *shrinker) if (!shrinker_debugfs_root) return 0; - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); if (shrinker->debugfs_entry) goto fail; @@ -196,7 +196,7 @@ int shrinker_debugfs_add(struct shrinker *shrinker) &shrinker_debugfs_scan_fops); fail: - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); return ret; } @@ -215,7 +215,7 @@ int shrinker_debugfs_rename(struct shrinker *shrinker, const char *fmt, ...) if (!new) return -ENOMEM; - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); old = shrinker->name; shrinker->name = new; @@ -233,7 +233,7 @@ int shrinker_debugfs_rename(struct shrinker *shrinker, const char *fmt, ...) shrinker->debugfs_entry = entry; } - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); kfree_const(old); @@ -246,7 +246,7 @@ struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker, { struct dentry *entry = shrinker->debugfs_entry; - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); kfree_const(shrinker->name); shrinker->name = NULL; @@ -257,7 +257,7 @@ struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker, */ smp_wmb(); shrinker->debugfs_entry = NULL; - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); return entry; }