The patch titled Subject: bcache: dynamically allocate the md-bcache shrinker has been added to the -mm mm-unstable branch. Its filename is bcache-dynamically-allocate-the-md-bcache-shrinker.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/bcache-dynamically-allocate-the-md-bcache-shrinker.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx> Subject: bcache: dynamically allocate the md-bcache shrinker Date: Mon, 11 Sep 2023 17:44:25 +0800 In preparation for implementing lockless slab shrink, use new APIs to dynamically allocate the md-bcache shrinker, 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 cache_set. Link: https://lkml.kernel.org/r/20230911094444.68966-27-zhengqi.arch@xxxxxxxxxxxxx Signed-off-by: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx> Cc: Coly Li <colyli@xxxxxxx> Cc: Kent Overstreet <kent.overstreet@xxxxxxxxx> Cc: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx> Cc: Alasdair Kergon <agk@xxxxxxxxxx> Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx> 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: Chris Mason <clm@xxxxxx> Cc: Christian Brauner <brauner@xxxxxxxxxx> Cc: Christian Koenig <christian.koenig@xxxxxxx> Cc: Chuck Lever <cel@xxxxxxxxxx> 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: David Sterba <dsterba@xxxxxxxx> 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: Josef Bacik <josef@xxxxxxxxxxxxxx> Cc: Juergen Gross <jgross@xxxxxxxx> 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: Muchun Song <songmuchun@xxxxxxxxxxxxx> 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> --- drivers/md/bcache/bcache.h | 2 +- drivers/md/bcache/btree.c | 29 +++++++++++++++++------------ drivers/md/bcache/sysfs.c | 3 ++- 3 files changed, 20 insertions(+), 14 deletions(-) --- a/drivers/md/bcache/bcache.h~bcache-dynamically-allocate-the-md-bcache-shrinker +++ a/drivers/md/bcache/bcache.h @@ -541,7 +541,7 @@ struct cache_set { struct bio_set bio_split; /* For the btree cache */ - struct shrinker shrink; + struct shrinker *shrink; /* For the btree cache and anything allocation related */ struct mutex bucket_lock; --- a/drivers/md/bcache/btree.c~bcache-dynamically-allocate-the-md-bcache-shrinker +++ a/drivers/md/bcache/btree.c @@ -667,7 +667,7 @@ out_unlock: static unsigned long bch_mca_scan(struct shrinker *shrink, struct shrink_control *sc) { - struct cache_set *c = container_of(shrink, struct cache_set, shrink); + struct cache_set *c = shrink->private_data; struct btree *b, *t; unsigned long i, nr = sc->nr_to_scan; unsigned long freed = 0; @@ -734,7 +734,7 @@ out: static unsigned long bch_mca_count(struct shrinker *shrink, struct shrink_control *sc) { - struct cache_set *c = container_of(shrink, struct cache_set, shrink); + struct cache_set *c = shrink->private_data; if (c->shrinker_disabled) return 0; @@ -752,8 +752,8 @@ void bch_btree_cache_free(struct cache_s closure_init_stack(&cl); - if (c->shrink.list.next) - unregister_shrinker(&c->shrink); + if (c->shrink) + shrinker_free(c->shrink); mutex_lock(&c->bucket_lock); @@ -828,14 +828,19 @@ int bch_btree_cache_alloc(struct cache_s c->verify_data = NULL; #endif - c->shrink.count_objects = bch_mca_count; - c->shrink.scan_objects = bch_mca_scan; - c->shrink.seeks = 4; - c->shrink.batch = c->btree_pages * 2; - - if (register_shrinker(&c->shrink, "md-bcache:%pU", c->set_uuid)) - pr_warn("bcache: %s: could not register shrinker\n", - __func__); + c->shrink = shrinker_alloc(0, "md-bcache:%pU", c->set_uuid); + if (!c->shrink) { + pr_warn("bcache: %s: could not allocate shrinker\n", __func__); + return 0; + } + + c->shrink->count_objects = bch_mca_count; + c->shrink->scan_objects = bch_mca_scan; + c->shrink->seeks = 4; + c->shrink->batch = c->btree_pages * 2; + c->shrink->private_data = c; + + shrinker_register(c->shrink); return 0; } --- a/drivers/md/bcache/sysfs.c~bcache-dynamically-allocate-the-md-bcache-shrinker +++ a/drivers/md/bcache/sysfs.c @@ -866,7 +866,8 @@ STORE(__bch_cache_set) sc.gfp_mask = GFP_KERNEL; sc.nr_to_scan = strtoul_or_return(buf); - c->shrink.scan_objects(&c->shrink, &sc); + if (c->shrink) + c->shrink->scan_objects(c->shrink, &sc); } sysfs_strtoul_clamp(congested_read_threshold_us, _ 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