The patch titled
Subject: fs: super: dynamically allocate the s_shrink
has been added to the -mm mm-unstable branch. Its filename is
fs-super-dynamically-allocate-the-s_shrink.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/fs-super-dynamically-allocate-the-s_shrink.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
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>
Cc: Chris Mason <clm@xxxxxx>
Cc: Josef Bacik <josef@xxxxxxxxxxxxxx>
Cc: David Sterba <dsterba@xxxxxxxx>
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
mm-move-some-shrinker-related-function-declarations-to-mm-internalh.patch
mm-vmscan-move-shrinker-related-code-into-a-separate-file.patch
mm-shrinker-remove-redundant-shrinker_rwsem-in-debugfs-operations.patch
drm-ttm-introduce-pool_shrink_rwsem.patch
mm-shrinker-add-infrastructure-for-dynamically-allocating-shrinker.patch
kvm-mmu-dynamically-allocate-the-x86-mmu-shrinker.patch
binder-dynamically-allocate-the-android-binder-shrinker.patch
drm-ttm-dynamically-allocate-the-drm-ttm_pool-shrinker.patch
xenbus-backend-dynamically-allocate-the-xen-backend-shrinker.patch
erofs-dynamically-allocate-the-erofs-shrinker.patch
f2fs-dynamically-allocate-the-f2fs-shrinker.patch
gfs2-dynamically-allocate-the-gfs2-glock-shrinker.patch
gfs2-dynamically-allocate-the-gfs2-qd-shrinker.patch
nfsv42-dynamically-allocate-the-nfs-xattr-shrinkers.patch
nfs-dynamically-allocate-the-nfs-acl-shrinker.patch
nfsd-dynamically-allocate-the-nfsd-filecache-shrinker.patch
quota-dynamically-allocate-the-dquota-cache-shrinker.patch
ubifs-dynamically-allocate-the-ubifs-slab-shrinker.patch
rcu-dynamically-allocate-the-rcu-lazy-shrinker.patch
rcu-dynamically-allocate-the-rcu-kfree-shrinker.patch
mm-thp-dynamically-allocate-the-thp-related-shrinkers.patch
sunrpc-dynamically-allocate-the-sunrpc_cred-shrinker.patch
mm-workingset-dynamically-allocate-the-mm-shadow-shrinker.patch
drm-i915-dynamically-allocate-the-i915_gem_mm-shrinker.patch
drm-msm-dynamically-allocate-the-drm-msm_gem-shrinker.patch
drm-panfrost-dynamically-allocate-the-drm-panfrost-shrinker.patch
dm-dynamically-allocate-the-dm-bufio-shrinker.patch
dm-zoned-dynamically-allocate-the-dm-zoned-meta-shrinker.patch
md-raid5-dynamically-allocate-the-md-raid5-shrinker.patch
bcache-dynamically-allocate-the-md-bcache-shrinker.patch
vmw_balloon-dynamically-allocate-the-vmw-balloon-shrinker.patch
virtio_balloon-dynamically-allocate-the-virtio-balloon-shrinker.patch
mbcache-dynamically-allocate-the-mbcache-shrinker.patch
ext4-dynamically-allocate-the-ext4-es-shrinker.patch
jbd2ext4-dynamically-allocate-the-jbd2-journal-shrinker.patch
nfsd-dynamically-allocate-the-nfsd-client-shrinker.patch
nfsd-dynamically-allocate-the-nfsd-reply-shrinker.patch
xfs-dynamically-allocate-the-xfs-buf-shrinker.patch
xfs-dynamically-allocate-the-xfs-inodegc-shrinker.patch
xfs-dynamically-allocate-the-xfs-qm-shrinker.patch
zsmalloc-dynamically-allocate-the-mm-zspool-shrinker.patch
fs-super-dynamically-allocate-the-s_shrink.patch
mm-shrinker-remove-old-apis.patch
mm-shrinker-add-a-secondary-array-for-shrinker_info-map-nr_deferred.patch
mm-shrinker-rename-preallocunregister_memcg_shrinker-to-shrinker_memcg_allocremove.patch
mm-shrinker-make-global-slab-shrink-lockless.patch
mm-shrinker-make-memcg-slab-shrink-lockless.patch
mm-shrinker-hold-write-lock-to-reparent-shrinker-nr_deferred.patch
mm-shrinker-convert-shrinker_rwsem-to-mutex.patch
