The quilt patch titled Subject: fs: super: dynamically allocate the s_shrink has been removed from the -mm tree. Its filename was fs-super-dynamically-allocate-the-s_shrink.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx> Subject: fs: super: dynamically allocate the s_shrink Date: Mon, 11 Sep 2023 17:44:37 +0800 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. Link: https://lkml.kernel.org/r/20230911094444.68966-39-zhengqi.arch@xxxxxxxxxxxxx Signed-off-by: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx> Reviewed-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> Acked-by: David Sterba <dsterba@xxxxxxxx> Cc: Chris Mason <clm@xxxxxx> Cc: Josef Bacik <josef@xxxxxxxxxxxxxx> Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Christian Brauner <brauner@xxxxxxxxxx> Cc: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx> Cc: Alasdair Kergon <agk@xxxxxxxxxx> Cc: Alyssa Rosenzweig <alyssa.rosenzweig@xxxxxxxxxxxxx> Cc: Andreas Dilger <adilger.kernel@xxxxxxxxx> Cc: Andreas Gruenbacher <agruenba@xxxxxxxxxx> Cc: Anna Schumaker <anna@xxxxxxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Cc: Bob Peterson <rpeterso@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Carlos Llamas <cmllamas@xxxxxxxxxx> Cc: Chandan Babu R <chandan.babu@xxxxxxxxxx> Cc: Chao Yu <chao@xxxxxxxxxx> Cc: Christian Koenig <christian.koenig@xxxxxxx> Cc: Chuck Lever <cel@xxxxxxxxxx> Cc: Coly Li <colyli@xxxxxxx> Cc: Dai Ngo <Dai.Ngo@xxxxxxxxxx> Cc: Daniel Vetter <daniel@xxxxxxxx> Cc: Daniel Vetter <daniel.vetter@xxxxxxxx> Cc: "Darrick J. Wong" <djwong@xxxxxxxxxx> Cc: Dave Chinner <david@xxxxxxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: David Airlie <airlied@xxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> Cc: Gao Xiang <hsiangkao@xxxxxxxxxxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: Huang Rui <ray.huang@xxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> Cc: Jan Kara <jack@xxxxxxx> Cc: Jason Wang <jasowang@xxxxxxxxxx> Cc: Jeff Layton <jlayton@xxxxxxxxxx> Cc: Jeffle Xu <jefflexu@xxxxxxxxxxxxxxxxx> Cc: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx> Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx> Cc: Juergen Gross <jgross@xxxxxxxx> Cc: Kent Overstreet <kent.overstreet@xxxxxxxxx> Cc: Kirill Tkhai <tkhai@xxxxx> Cc: Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx> Cc: "Michael S. Tsirkin" <mst@xxxxxxxxxx> Cc: Mike Snitzer <snitzer@xxxxxxxxxx> Cc: Minchan Kim <minchan@xxxxxxxxxx> Cc: Muchun Song <muchun.song@xxxxxxxxx> Cc: Nadav Amit <namit@xxxxxxxxxx> Cc: Neil Brown <neilb@xxxxxxx> Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@xxxxxxxx> Cc: Olga Kornievskaia <kolga@xxxxxxxxxx> Cc: Paul E. McKenney <paulmck@xxxxxxxxxx> Cc: Richard Weinberger <richard@xxxxxx> Cc: Rob Clark <robdclark@xxxxxxxxx> Cc: Rob Herring <robh@xxxxxxxxxx> Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> Cc: Roman Gushchin <roman.gushchin@xxxxxxxxx> Cc: Sean Paul <sean@xxxxxxxxxx> Cc: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx> Cc: Song Liu <song@xxxxxxxxxx> Cc: Stefano Stabellini <sstabellini@xxxxxxxxxx> Cc: Steven Price <steven.price@xxxxxxx> Cc: "Theodore Ts'o" <tytso@xxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Tomeu Vizoso <tomeu.vizoso@xxxxxxxxxxxxx> Cc: Tom Talpey <tom@xxxxxxxxxx> Cc: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxxxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Cc: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx> Cc: Yue Hu <huyue2@xxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- 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(-) --- a/fs/btrfs/super.c~fs-super-dynamically-allocate-the-s_shrink +++ a/fs/btrfs/super.c @@ -1519,7 +1519,7 @@ static struct dentry *btrfs_mount_root(s error = -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 = fs_type; error = btrfs_fill_super(s, fs_devices, data); --- a/fs/kernfs/mount.c~fs-super-dynamically-allocate-the-s_shrink +++ a/fs/kernfs/mount.c @@ -265,7 +265,7 @@ static int kernfs_fill_super(struct supe sb->s_time_gran = 1; /* sysfs dentries and inodes don't require IO to create */ - sb->s_shrink.seeks = 0; + sb->s_shrink->seeks = 0; /* get root inode, initialize and unlock it */ down_read(&kf_root->kernfs_rwsem); --- a/fs/proc/root.c~fs-super-dynamically-allocate-the-s_shrink +++ a/fs/proc/root.c @@ -188,7 +188,7 @@ static int proc_fill_super(struct super_ s->s_stack_depth = FILESYSTEM_MAX_STACK_DEPTH; /* procfs dentries and inodes don't require IO to create */ - s->s_shrink.seeks = 0; + s->s_shrink->seeks = 0; pde_get(&proc_root); root_inode = proc_get_inode(s, &proc_root); --- a/fs/super.c~fs-super-dynamically-allocate-the-s_shrink +++ a/fs/super.c @@ -191,7 +191,7 @@ static unsigned long super_cache_scan(st long dentries; long inodes; - sb = container_of(shrink, struct super_block, s_shrink); + sb = shrink->private_data; /* * Deadlock avoidance. We may hold various FS locks, and we don't want @@ -244,7 +244,7 @@ static unsigned long super_cache_count(s struct super_block *sb; long total_objects = 0; - sb = container_of(shrink, struct super_block, s_shrink); + sb = shrink->private_data; /* * We don't call super_trylock_shared() here as it is a scalability @@ -306,7 +306,7 @@ static void destroy_unused_super(struct 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(s s->s_time_min = TIME64_MIN; s->s_time_max = TIME64_MAX; - s->s_shrink.seeks = DEFAULT_SEEKS; - s->s_shrink.scan_objects = super_cache_scan; - s->s_shrink.count_objects = super_cache_count; - s->s_shrink.batch = 1024; - s->s_shrink.flags = SHRINKER_NUMA_AWARE | SHRINKER_MEMCG_AWARE; - if (prealloc_shrinker(&s->s_shrink, "sb-%s", type->name)) + s->s_shrink = 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 = super_cache_scan; + s->s_shrink->count_objects = super_cache_count; + s->s_shrink->batch = 1024; + s->s_shrink->private_data = 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; @@ -477,7 +480,7 @@ void deactivate_locked_super(struct supe { struct file_system_type *fs = 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); kill_super_notify(s); @@ -818,7 +821,7 @@ retry: 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; share_extant_sb: @@ -901,7 +904,7 @@ retry: 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 mutex_unlock(&bdev->bd_fsfreeze_mutex); 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; --- a/include/linux/fs.h~fs-super-dynamically-allocate-the-s_shrink +++ a/include/linux/fs.h @@ -1265,7 +1265,7 @@ struct super_block { const struct dentry_operations *s_d_op; /* default d_op for dentries */ - struct shrinker s_shrink; /* per-sb shrinker handle */ + struct shrinker *s_shrink; /* per-sb shrinker handle */ /* Number of inodes with nlink == 0 but still referenced */ atomic_long_t s_remove_count; _ Patches currently in -mm which might be from zhengqi.arch@xxxxxxxxxxxxx are