The patch titled Subject: md/raid5: dynamically allocate the md-raid5 shrinker has been added to the -mm mm-unstable branch. Its filename is md-raid5-dynamically-allocate-the-md-raid5-shrinker.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/md-raid5-dynamically-allocate-the-md-raid5-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: md/raid5: dynamically allocate the md-raid5 shrinker Date: Mon, 11 Sep 2023 17:44:24 +0800 In preparation for implementing lockless slab shrink, use new APIs to dynamically allocate the md-raid5 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 r5conf. Link: https://lkml.kernel.org/r/20230911094444.68966-26-zhengqi.arch@xxxxxxxxxxxxx Signed-off-by: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx> Reviewed-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> Reviewed-by: Song Liu <song@xxxxxxxxxx> 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: 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: 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: 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: 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/raid5.c | 26 +++++++++++++++----------- drivers/md/raid5.h | 2 +- 2 files changed, 16 insertions(+), 12 deletions(-) --- a/drivers/md/raid5.c~md-raid5-dynamically-allocate-the-md-raid5-shrinker +++ a/drivers/md/raid5.c @@ -7401,7 +7401,7 @@ static void free_conf(struct r5conf *con log_exit(conf); - unregister_shrinker(&conf->shrinker); + shrinker_free(conf->shrinker); free_thread_groups(conf); shrink_stripes(conf); raid5_free_percpu(conf); @@ -7449,7 +7449,7 @@ static int raid5_alloc_percpu(struct r5c static unsigned long raid5_cache_scan(struct shrinker *shrink, struct shrink_control *sc) { - struct r5conf *conf = container_of(shrink, struct r5conf, shrinker); + struct r5conf *conf = shrink->private_data; unsigned long ret = SHRINK_STOP; if (mutex_trylock(&conf->cache_size_mutex)) { @@ -7470,7 +7470,7 @@ static unsigned long raid5_cache_scan(st static unsigned long raid5_cache_count(struct shrinker *shrink, struct shrink_control *sc) { - struct r5conf *conf = container_of(shrink, struct r5conf, shrinker); + struct r5conf *conf = shrink->private_data; if (conf->max_nr_stripes < conf->min_nr_stripes) /* unlikely, but not impossible */ @@ -7705,18 +7705,22 @@ static struct r5conf *setup_conf(struct * it reduces the queue depth and so can hurt throughput. * So set it rather large, scaled by number of devices. */ - conf->shrinker.seeks = DEFAULT_SEEKS * conf->raid_disks * 4; - conf->shrinker.scan_objects = raid5_cache_scan; - conf->shrinker.count_objects = raid5_cache_count; - conf->shrinker.batch = 128; - conf->shrinker.flags = 0; - ret = register_shrinker(&conf->shrinker, "md-raid5:%s", mdname(mddev)); - if (ret) { - pr_warn("md/raid:%s: couldn't register shrinker.\n", + conf->shrinker = shrinker_alloc(0, "md-raid5:%s", mdname(mddev)); + if (!conf->shrinker) { + ret = -ENOMEM; + pr_warn("md/raid:%s: couldn't allocate shrinker.\n", mdname(mddev)); goto abort; } + conf->shrinker->seeks = DEFAULT_SEEKS * conf->raid_disks * 4; + conf->shrinker->scan_objects = raid5_cache_scan; + conf->shrinker->count_objects = raid5_cache_count; + conf->shrinker->batch = 128; + conf->shrinker->private_data = conf; + + shrinker_register(conf->shrinker); + sprintf(pers_name, "raid%d", mddev->new_level); rcu_assign_pointer(conf->thread, md_register_thread(raid5d, mddev, pers_name)); --- a/drivers/md/raid5.h~md-raid5-dynamically-allocate-the-md-raid5-shrinker +++ a/drivers/md/raid5.h @@ -670,7 +670,7 @@ struct r5conf { wait_queue_head_t wait_for_stripe; wait_queue_head_t wait_for_overlap; unsigned long cache_state; - struct shrinker shrinker; + struct shrinker *shrinker; int pool_size; /* number of disks in stripeheads in pool */ spinlock_t device_lock; struct disk_info *disks; _ 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