From patchwork Thu Jun 22 08:53:34 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qi Zheng X-Patchwork-Id: 13288757 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 E4E8EC001DD for ; Thu, 22 Jun 2023 09:06:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232068AbjFVJGZ (ORCPT ); Thu, 22 Jun 2023 05:06:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48892 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232324AbjFVJF2 (ORCPT ); Thu, 22 Jun 2023 05:05:28 -0400 Received: from mail-pg1-x52c.google.com (mail-pg1-x52c.google.com [IPv6:2607:f8b0:4864:20::52c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0BD074C0C for ; Thu, 22 Jun 2023 01:58:26 -0700 (PDT) Received: by mail-pg1-x52c.google.com with SMTP id 41be03b00d2f7-51f64817809so680244a12.1 for ; Thu, 22 Jun 2023 01:58:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1687424268; x=1690016268; 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=+P5gj8bno5Yz104PoCsSeC7OSXGzrjC+L9aN78tCOOI=; b=jvhIGmYE039/syWqcfLyIdo6t9Qplyt6OsSxUBVvxtsPAkw48Ft91VW4Wz2O26wmhx R0vxBU2Gya4gcRkfUKW9xk7qtBQ/FB/itjiP7zdM6kYiVPyrZbA9p3LfIx3f71WW1xO7 LLQ+0DljNwUv19wViW0KnJsUJ8+fuKrQN9IBdM3/tIdgoFSPmAiPoFKu75bet98dvkR/ 1RKnODQtDxONo/sndY6eLEsUvIJFr3WP9l67MNEVgdfQojcwBUWJp7hhTFie6SRhHC3h g1EMHwWUjxMnky7BCMGJqXeVS7+DBkpxiGCDfvbg7pDqaD88DLgjwvpVG1NnvXM5z1NX rt6Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1687424268; x=1690016268; 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=+P5gj8bno5Yz104PoCsSeC7OSXGzrjC+L9aN78tCOOI=; b=fOgTd1QPxZxZ9B5AmqWpC/btCc3euIH7VebdC+M93Mn9+uYI7C9QKhNfomVDZxLMfw o1dUnBt+LiarCPxVz8hZVBa+sffwmsCJADq1bwW0dsj1lFyuGFkESmPZA/RtF9pMNqth vzgb8KupjDoirFDZVBepZ976AuOsDltegvHZI7FPufv5Xu5cJwWr8ATf8V1RYLFOeVZV liDEGAtIk/21lh5elzWjG94h31S01lMz7irXu6g18Hm1g4TVyBEdYSsMGvDroUav4iZM iH6x5mgQnqnGrfwTzwPF2NOuM5WMK5voqfeH6A9+O8WwLmpNjxxdTx1vZ5KioayX11vj 5vnA== X-Gm-Message-State: AC+VfDyU0FwtKNA8VCVbk2UCaQi7EWoHTDlWeTFZKy3j58G2MFD1iWB1 uiX2bbf05ZDDFjEkKH5dNiTkGA== X-Google-Smtp-Source: ACHHUZ57rUw3vY36SztXPXN7lhzSsB9eXMClAkEXukaFLir2ldlvIHkHUZcbPwVIoKn5tOhLnnwBWg== X-Received: by 2002:a17:902:ecc6:b0:1ae:1364:6086 with SMTP id a6-20020a170902ecc600b001ae13646086mr21606033plh.2.1687424268179; Thu, 22 Jun 2023 01:57:48 -0700 (PDT) Received: from C02DW0BEMD6R.bytedance.net ([139.177.225.254]) by smtp.gmail.com with ESMTPSA id h2-20020a170902f7c200b001b549fce345sm4806971plw.230.2023.06.22.01.57.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 22 Jun 2023 01:57:47 -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 28/29] mm: shrinkers: convert shrinker_rwsem to mutex Date: Thu, 22 Jun 2023 16:53:34 +0800 Message-Id: <20230622085335.77010-29-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 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@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 +- drivers/md/dm-thin-metadata.c | 2 +- fs/super.c | 2 +- mm/shrinker_debug.c | 14 +++++++------- mm/vmscan.c | 34 +++++++++++++++++----------------- 5 files changed, 27 insertions(+), 27 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/drivers/md/dm-thin-metadata.c b/drivers/md/dm-thin-metadata.c index fd464fb024c3..9f5cb52c5763 100644 --- a/drivers/md/dm-thin-metadata.c +++ b/drivers/md/dm-thin-metadata.c @@ -1887,7 +1887,7 @@ int dm_pool_abort_metadata(struct dm_pool_metadata *pmd) * Replacement block manager (new_bm) is created and old_bm destroyed outside of * pmd root_lock to avoid ABBA deadlock that would result (due to life-cycle of * shrinker associated with the block manager's bufio client vs pmd root_lock). - * - must take shrinker_rwsem without holding pmd->root_lock + * - must take shrinker_mutex without holding pmd->root_lock */ new_bm = dm_block_manager_create(pmd->bdev, THIN_METADATA_BLOCK_SIZE << SECTOR_SHIFT, THIN_MAX_CONCURRENT_LOCKS); diff --git a/fs/super.c b/fs/super.c index 791342bb8ac9..471800ff793a 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_debug.c b/mm/shrinker_debug.c index c18fa9b6b7f0..7ad903f84463 100644 --- a/mm/shrinker_debug.c +++ b/mm/shrinker_debug.c @@ -7,7 +7,7 @@ #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); @@ -177,7 +177,7 @@ int shrinker_debugfs_add(struct shrinker *shrinker) char buf[128]; int id; - lockdep_assert_held(&shrinker_rwsem); + lockdep_assert_held(&shrinker_mutex); /* debugfs isn't initialized yet, add debugfs entries later. */ if (!shrinker_debugfs_root) @@ -220,7 +220,7 @@ 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; @@ -238,7 +238,7 @@ 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); @@ -251,7 +251,7 @@ struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker, { struct dentry *entry = shrinker->debugfs_entry; - lockdep_assert_held(&shrinker_rwsem); + lockdep_assert_held(&shrinker_mutex); kfree_const(shrinker->name); shrinker->name = NULL; @@ -280,14 +280,14 @@ static int __init shrinker_debugfs_init(void) shrinker_debugfs_root = dentry; /* Create debugfs entries for shrinkers registered at boot */ - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); list_for_each_entry(shrinker, &shrinker_list, list) if (!shrinker->debugfs_entry) { ret = shrinker_debugfs_add(shrinker); if (ret) break; } - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); return ret; } diff --git a/mm/vmscan.c b/mm/vmscan.c index 0711b63e68d9..bcdd97caa403 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -35,7 +35,7 @@ #include #include #include -#include +#include #include #include #include @@ -190,7 +190,7 @@ struct scan_control { int vm_swappiness = 60; LIST_HEAD(shrinker_list); -DECLARE_RWSEM(shrinker_rwsem); +DEFINE_MUTEX(shrinker_mutex); #ifdef CONFIG_MEMCG static int shrinker_nr_max; @@ -210,7 +210,7 @@ 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, @@ -283,7 +283,7 @@ int alloc_shrinker_info(struct mem_cgroup *memcg) int nid, size, ret = 0; int map_size, defer_size = 0; - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); map_size = shrinker_map_size(shrinker_nr_max); defer_size = shrinker_defer_size(shrinker_nr_max); size = map_size + defer_size; @@ -299,7 +299,7 @@ int alloc_shrinker_info(struct mem_cgroup *memcg) info->map_nr_max = shrinker_nr_max; rcu_assign_pointer(memcg->nodeinfo[nid]->shrinker_info, info); } - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); return ret; } @@ -315,7 +315,7 @@ static int expand_shrinker_info(int new_id) if (!root_mem_cgroup) goto out; - lockdep_assert_held(&shrinker_rwsem); + lockdep_assert_held(&shrinker_mutex); map_size = shrinker_map_size(new_nr_max); defer_size = shrinker_defer_size(new_nr_max); @@ -364,7 +364,7 @@ static int prealloc_memcg_shrinker(struct shrinker *shrinker) if (mem_cgroup_disabled()) return -ENOSYS; - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); id = idr_alloc(&shrinker_idr, shrinker, 0, 0, GFP_KERNEL); if (id < 0) goto unlock; @@ -378,7 +378,7 @@ static int prealloc_memcg_shrinker(struct shrinker *shrinker) shrinker->id = id; ret = 0; unlock: - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); return ret; } @@ -388,7 +388,7 @@ static void unregister_memcg_shrinker(struct shrinker *shrinker) BUG_ON(id < 0); - lockdep_assert_held(&shrinker_rwsem); + lockdep_assert_held(&shrinker_mutex); idr_remove(&shrinker_idr, id); } @@ -433,7 +433,7 @@ 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); @@ -442,7 +442,7 @@ void reparent_shrinker_deferred(struct mem_cgroup *memcg) atomic_long_add(nr, &parent_info->nr_deferred[i]); } } - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); } static bool cgroup_reclaim(struct scan_control *sc) @@ -743,9 +743,9 @@ void free_prealloced_shrinker(struct shrinker *shrinker) shrinker->name = NULL; #endif if (shrinker->flags & SHRINKER_MEMCG_AWARE) { - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); unregister_memcg_shrinker(shrinker); - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); return; } @@ -755,13 +755,13 @@ void free_prealloced_shrinker(struct shrinker *shrinker) void register_shrinker_prepared(struct shrinker *shrinker) { - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); refcount_set(&shrinker->refcount, 1); init_completion(&shrinker->completion_wait); list_add_tail_rcu(&shrinker->list, &shrinker_list); shrinker->flags |= SHRINKER_REGISTERED; shrinker_debugfs_add(shrinker); - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); } static int __register_shrinker(struct shrinker *shrinker) @@ -815,13 +815,13 @@ void unregister_shrinker(struct shrinker *shrinker) shrinker_put(shrinker); wait_for_completion(&shrinker->completion_wait); - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); list_del_rcu(&shrinker->list); shrinker->flags &= ~SHRINKER_REGISTERED; if (shrinker->flags & SHRINKER_MEMCG_AWARE) unregister_memcg_shrinker(shrinker); debugfs_entry = shrinker_debugfs_detach(shrinker, &debugfs_id); - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); shrinker_debugfs_remove(debugfs_entry, debugfs_id);