From nobody Thu Sep 11 22:30:18 2025 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 56360CA0EC1 for ; Mon, 11 Sep 2023 21:39:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350212AbjIKVgG (ORCPT ); Mon, 11 Sep 2023 17:36:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37678 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236114AbjIKJvE (ORCPT ); Mon, 11 Sep 2023 05:51:04 -0400 Received: from mail-pg1-x535.google.com (mail-pg1-x535.google.com [IPv6:2607:f8b0:4864:20::535]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 81A8AE50 for ; Mon, 11 Sep 2023 02:50:59 -0700 (PDT) Received: by mail-pg1-x535.google.com with SMTP id 41be03b00d2f7-5657ca46a56so445424a12.0 for ; Mon, 11 Sep 2023 02:50:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1694425859; x=1695030659; darn=vger.kernel.org; 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=UwQSoSJR+jSGtu7F9A/uGElinPV2h0dmFylLKakGH3E=; b=IA+xNJX9lpoZOvs70Szvr9jKE8+886p1h7TFx5fxt4u29LBTQ2nXb0/azdBeI05PIb sFudKsQ2IOM6VFAyL/QimZeubcMBNmk8fpH6+QuM90rZ5S9eGxOQpd+tGTHGuzCt/IzP e1beu0ffbKrkWa/Gi+8tjlnezoYcQ/4l6/mCZG/Ns/zS6i2rfhuQCcqjUT2RlAErK3Ez iGLCvdipvnx4txhKvlkfLzZTp/E/12Z0HpsQzvni6UhPUHXkyyDNOuYE3sgWBwRQZnzg 8PISQ56FAZBJMqXNoaFsY+e4MndQdgLIH9b44YDrLaghg0AEvXtnj4/Cp+ou4Ly8ImCD 1TDA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1694425859; x=1695030659; 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=UwQSoSJR+jSGtu7F9A/uGElinPV2h0dmFylLKakGH3E=; b=wzVh+tcv33CfTRNcji4rvpMF/WFfDR54WaNgaocSl5TcxCkbU+a1QQC6JXEQpAYTsC iPHUjHrlpUvCF+eBh1RSPN+SO+zS0G1A0vLQM0mTftUbClijVnU695vVFGQsuGuvu0U/ OxHq6VzHbBqS8ZGmf2trBm53mi1jTaBipxf6a4Et5lvvzjZDmBBjUr+d5iyqBLC/8OBI POOTkRXxH+78w32Slzd0hDXCw29R6SHmVuemxpZ8OAL9rNIk7N/3dDFdyLiEADqyAr9U GKhdOkyIOYsVTMa1nFLealX1ZGoc8SV+ulPUt+tGTRFZkVvE4oq41sSNEWnBRyfJYBWK 8BSw== X-Gm-Message-State: AOJu0Yw0xoFK+cOHexHRzU4s37H2M0DDfDc9ejsPF/kjPClHt82CTkvt Wlt6lR88oir7b+AU7oOvI6P/rw== X-Google-Smtp-Source: AGHT+IFK0C5cGs7QePEp9uLcPywDnGod8IFfwet3Jfbl6uzPvoZmscAh5Bx6Hmh6im2BgxS0qDp7eg== X-Received: by 2002:a05:6a20:4425:b0:14d:4ab5:5e3c with SMTP id ce37-20020a056a20442500b0014d4ab55e3cmr13477043pzb.1.1694425858977; Mon, 11 Sep 2023 02:50:58 -0700 (PDT) Received: from C02DW0BEMD6R.bytedance.net ([203.208.167.146]) by smtp.gmail.com with ESMTPSA id az7-20020a170902a58700b001bdc2fdcf7esm5988188plb.129.2023.09.11.02.50.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 11 Sep 2023 02:50:58 -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, linux-fsdevel@vger.kernel.org, Qi Zheng , Muchun Song , Chris Mason , Josef Bacik , David Sterba , Alexander Viro , linux-btrfs@vger.kernel.org Subject: [PATCH v6 38/45] fs: super: dynamically allocate the s_shrink Date: Mon, 11 Sep 2023 17:44:37 +0800 Message-Id: <20230911094444.68966-39-zhengqi.arch@bytedance.com> X-Mailer: git-send-email 2.24.3 (Apple Git-128) In-Reply-To: <20230911094444.68966-1-zhengqi.arch@bytedance.com> References: <20230911094444.68966-1-zhengqi.arch@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" In preparation for implementing lockless slab shrink, use new APIs to dynamically allocate the s_shrink, so that it can be freed asynchronously via RCU. Then it doesn't need to wait for RCU read-side critical section when releasing the struct super_block. Signed-off-by: Qi Zheng Reviewed-by: Muchun Song CC: Chris Mason CC: Josef Bacik CC: David Sterba CC: Alexander Viro CC: Christian Brauner CC: linux-btrfs@vger.kernel.org --- fs/btrfs/super.c | 2 +- fs/kernfs/mount.c | 2 +- fs/proc/root.c | 2 +- fs/super.c | 33 ++++++++++++++++++--------------- include/linux/fs.h | 2 +- 5 files changed, 22 insertions(+), 19 deletions(-) diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 09bfe68d2ea3..3b165d9967bb 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1519,7 +1519,7 @@ static struct dentry *btrfs_mount_root(struct file_sy= stem_type *fs_type, error =3D -EBUSY; } else { snprintf(s->s_id, sizeof(s->s_id), "%pg", bdev); - shrinker_debugfs_rename(&s->s_shrink, "sb-%s:%s", fs_type->name, + shrinker_debugfs_rename(s->s_shrink, "sb-%s:%s", fs_type->name, s->s_id); btrfs_sb(s)->bdev_holder =3D fs_type; error =3D btrfs_fill_super(s, fs_devices, data); diff --git a/fs/kernfs/mount.c b/fs/kernfs/mount.c index c4bf26142eec..79b96e74a8a0 100644 --- a/fs/kernfs/mount.c +++ b/fs/kernfs/mount.c @@ -265,7 +265,7 @@ static int kernfs_fill_super(struct super_block *sb, st= ruct kernfs_fs_context *k sb->s_time_gran =3D 1; =20 /* sysfs dentries and inodes don't require IO to create */ - sb->s_shrink.seeks =3D 0; + sb->s_shrink->seeks =3D 0; =20 /* get root inode, initialize and unlock it */ down_read(&kf_root->kernfs_rwsem); diff --git a/fs/proc/root.c b/fs/proc/root.c index 9191248f2dac..b55dbc70287b 100644 --- a/fs/proc/root.c +++ b/fs/proc/root.c @@ -188,7 +188,7 @@ static int proc_fill_super(struct super_block *s, struc= t fs_context *fc) s->s_stack_depth =3D FILESYSTEM_MAX_STACK_DEPTH; =20 /* procfs dentries and inodes don't require IO to create */ - s->s_shrink.seeks =3D 0; + s->s_shrink->seeks =3D 0; =20 pde_get(&proc_root); root_inode =3D proc_get_inode(s, &proc_root); diff --git a/fs/super.c b/fs/super.c index 2d762ce67f6e..adadf6689611 100644 --- a/fs/super.c +++ b/fs/super.c @@ -191,7 +191,7 @@ static unsigned long super_cache_scan(struct shrinker *= shrink, long dentries; long inodes; =20 - sb =3D container_of(shrink, struct super_block, s_shrink); + sb =3D shrink->private_data; =20 /* * Deadlock avoidance. We may hold various FS locks, and we don't want @@ -244,7 +244,7 @@ static unsigned long super_cache_count(struct shrinker = *shrink, struct super_block *sb; long total_objects =3D 0; =20 - sb =3D container_of(shrink, struct super_block, s_shrink); + sb =3D shrink->private_data; =20 /* * We don't call super_trylock_shared() here as it is a scalability @@ -306,7 +306,7 @@ static void destroy_unused_super(struct super_block *s) security_sb_free(s); put_user_ns(s->s_user_ns); kfree(s->s_subtype); - free_prealloced_shrinker(&s->s_shrink); + shrinker_free(s->s_shrink); /* no delays needed */ destroy_super_work(&s->destroy_work); } @@ -383,16 +383,19 @@ static struct super_block *alloc_super(struct file_sy= stem_type *type, int flags, s->s_time_min =3D TIME64_MIN; s->s_time_max =3D TIME64_MAX; =20 - s->s_shrink.seeks =3D DEFAULT_SEEKS; - s->s_shrink.scan_objects =3D super_cache_scan; - s->s_shrink.count_objects =3D super_cache_count; - s->s_shrink.batch =3D 1024; - s->s_shrink.flags =3D SHRINKER_NUMA_AWARE | SHRINKER_MEMCG_AWARE; - if (prealloc_shrinker(&s->s_shrink, "sb-%s", type->name)) + s->s_shrink =3D shrinker_alloc(SHRINKER_NUMA_AWARE | SHRINKER_MEMCG_AWARE, + "sb-%s", type->name); + if (!s->s_shrink) goto fail; - if (list_lru_init_memcg(&s->s_dentry_lru, &s->s_shrink)) + + s->s_shrink->scan_objects =3D super_cache_scan; + s->s_shrink->count_objects =3D super_cache_count; + s->s_shrink->batch =3D 1024; + s->s_shrink->private_data =3D s; + + if (list_lru_init_memcg(&s->s_dentry_lru, s->s_shrink)) goto fail; - if (list_lru_init_memcg(&s->s_inode_lru, &s->s_shrink)) + if (list_lru_init_memcg(&s->s_inode_lru, s->s_shrink)) goto fail; return s; =20 @@ -477,7 +480,7 @@ void deactivate_locked_super(struct super_block *s) { struct file_system_type *fs =3D s->s_type; if (atomic_dec_and_test(&s->s_active)) { - unregister_shrinker(&s->s_shrink); + shrinker_free(s->s_shrink); fs->kill_sb(s); =20 kill_super_notify(s); @@ -818,7 +821,7 @@ struct super_block *sget_fc(struct fs_context *fc, hlist_add_head(&s->s_instances, &s->s_type->fs_supers); spin_unlock(&sb_lock); get_filesystem(s->s_type); - register_shrinker_prepared(&s->s_shrink); + shrinker_register(s->s_shrink); return s; =20 share_extant_sb: @@ -901,7 +904,7 @@ struct super_block *sget(struct file_system_type *type, hlist_add_head(&s->s_instances, &type->fs_supers); spin_unlock(&sb_lock); get_filesystem(type); - register_shrinker_prepared(&s->s_shrink); + shrinker_register(s->s_shrink); return s; } EXPORT_SYMBOL(sget); @@ -1522,7 +1525,7 @@ int setup_bdev_super(struct super_block *sb, int sb_f= lags, mutex_unlock(&bdev->bd_fsfreeze_mutex); =20 snprintf(sb->s_id, sizeof(sb->s_id), "%pg", bdev); - shrinker_debugfs_rename(&sb->s_shrink, "sb-%s:%s", sb->s_type->name, + shrinker_debugfs_rename(sb->s_shrink, "sb-%s:%s", sb->s_type->name, sb->s_id); sb_set_blocksize(sb, block_size(bdev)); return 0; diff --git a/include/linux/fs.h b/include/linux/fs.h index 4aeb3fa11927..801ff3d66caa 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1265,7 +1265,7 @@ struct super_block { =20 const struct dentry_operations *s_d_op; /* default d_op for dentries */ =20 - struct shrinker s_shrink; /* per-sb shrinker handle */ + struct shrinker *s_shrink; /* per-sb shrinker handle */ =20 /* Number of inodes with nlink =3D=3D 0 but still referenced */ atomic_long_t s_remove_count; --=20 2.30.2