+ nfsd-dynamically-allocate-the-nfsd-reply-shrinker.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: nfsd: dynamically allocate the nfsd-reply shrinker
has been added to the -mm mm-unstable branch.  Its filename is
     nfsd-dynamically-allocate-the-nfsd-reply-shrinker.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/nfsd-dynamically-allocate-the-nfsd-reply-shrinker.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@bytedance.com>
Subject: nfsd: dynamically allocate the nfsd-reply shrinker
Date: Mon, 11 Sep 2023 17:44:32 +0800

In preparation for implementing lockless slab shrink, use new APIs to
dynamically allocate the nfsd-reply 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 nfsd_net.

Link: https://lkml.kernel.org/r/20230911094444.68966-34-zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Olga Kornievskaia <kolga@netapp.com>
Cc: Dai Ngo <Dai.Ngo@oracle.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Abhinav Kumar <quic_abhinavk@quicinc.com>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bob Peterson <rpeterso@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Carlos Llamas <cmllamas@google.com>
Cc: Chandan Babu R <chandan.babu@oracle.com>
Cc: Chao Yu <chao@kernel.org>
Cc: Chris Mason <clm@fb.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Christian Koenig <christian.koenig@amd.com>
Cc: Chuck Lever <cel@kernel.org>
Cc: Coly Li <colyli@suse.de>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Airlie <airlied@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Cc: Gao Xiang <hsiangkao@linux.alibaba.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Jeffle Xu <jefflexu@linux.alibaba.com>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Kirill Tkhai <tkhai@ya.ru>
Cc: Marijn Suijten <marijn.suijten@somainline.org>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Sean Paul <sean@poorly.run>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Song Liu <song@kernel.org>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Steven Price <steven.price@arm.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Cc: Yue Hu <huyue2@coolpad.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/nfsd/netns.h    |    2 +-
 fs/nfsd/nfscache.c |   31 ++++++++++++++++---------------
 2 files changed, 17 insertions(+), 16 deletions(-)

--- a/fs/nfsd/netns.h~nfsd-dynamically-allocate-the-nfsd-reply-shrinker
+++ a/fs/nfsd/netns.h
@@ -177,7 +177,7 @@ struct nfsd_net {
 	/* size of cache when we saw the longest hash chain */
 	unsigned int             longest_chain_cachesize;
 
-	struct shrinker		nfsd_reply_cache_shrinker;
+	struct shrinker		*nfsd_reply_cache_shrinker;
 
 	/* tracking server-to-server copy mounts */
 	spinlock_t              nfsd_ssc_lock;
--- a/fs/nfsd/nfscache.c~nfsd-dynamically-allocate-the-nfsd-reply-shrinker
+++ a/fs/nfsd/nfscache.c
@@ -201,26 +201,29 @@ int nfsd_reply_cache_init(struct nfsd_ne
 {
 	unsigned int hashsize;
 	unsigned int i;
-	int status = 0;
 
 	nn->max_drc_entries = nfsd_cache_size_limit();
 	atomic_set(&nn->num_drc_entries, 0);
 	hashsize = nfsd_hashsize(nn->max_drc_entries);
 	nn->maskbits = ilog2(hashsize);
 
-	nn->nfsd_reply_cache_shrinker.scan_objects = nfsd_reply_cache_scan;
-	nn->nfsd_reply_cache_shrinker.count_objects = nfsd_reply_cache_count;
-	nn->nfsd_reply_cache_shrinker.seeks = 1;
-	status = register_shrinker(&nn->nfsd_reply_cache_shrinker,
-				   "nfsd-reply:%s", nn->nfsd_name);
-	if (status)
-		return status;
-
 	nn->drc_hashtbl = kvzalloc(array_size(hashsize,
 				sizeof(*nn->drc_hashtbl)), GFP_KERNEL);
 	if (!nn->drc_hashtbl)
+		return -ENOMEM;
+
+	nn->nfsd_reply_cache_shrinker = shrinker_alloc(0, "nfsd-reply:%s",
+						       nn->nfsd_name);
+	if (!nn->nfsd_reply_cache_shrinker)
 		goto out_shrinker;
 
+	nn->nfsd_reply_cache_shrinker->scan_objects = nfsd_reply_cache_scan;
+	nn->nfsd_reply_cache_shrinker->count_objects = nfsd_reply_cache_count;
+	nn->nfsd_reply_cache_shrinker->seeks = 1;
+	nn->nfsd_reply_cache_shrinker->private_data = nn;
+
+	shrinker_register(nn->nfsd_reply_cache_shrinker);
+
 	for (i = 0; i < hashsize; i++) {
 		INIT_LIST_HEAD(&nn->drc_hashtbl[i].lru_head);
 		spin_lock_init(&nn->drc_hashtbl[i].cache_lock);
@@ -229,7 +232,7 @@ int nfsd_reply_cache_init(struct nfsd_ne
 
 	return 0;
 out_shrinker:
-	unregister_shrinker(&nn->nfsd_reply_cache_shrinker);
+	kvfree(nn->drc_hashtbl);
 	printk(KERN_ERR "nfsd: failed to allocate reply cache\n");
 	return -ENOMEM;
 }
@@ -239,7 +242,7 @@ void nfsd_reply_cache_shutdown(struct nf
 	struct nfsd_cacherep *rp;
 	unsigned int i;
 
-	unregister_shrinker(&nn->nfsd_reply_cache_shrinker);
+	shrinker_free(nn->nfsd_reply_cache_shrinker);
 
 	for (i = 0; i < nn->drc_hashsize; i++) {
 		struct list_head *head = &nn->drc_hashtbl[i].lru_head;
@@ -323,8 +326,7 @@ nfsd_prune_bucket_locked(struct nfsd_net
 static unsigned long
 nfsd_reply_cache_count(struct shrinker *shrink, struct shrink_control *sc)
 {
-	struct nfsd_net *nn = container_of(shrink,
-				struct nfsd_net, nfsd_reply_cache_shrinker);
+	struct nfsd_net *nn = shrink->private_data;
 
 	return atomic_read(&nn->num_drc_entries);
 }
@@ -343,8 +345,7 @@ nfsd_reply_cache_count(struct shrinker *
 static unsigned long
 nfsd_reply_cache_scan(struct shrinker *shrink, struct shrink_control *sc)
 {
-	struct nfsd_net *nn = container_of(shrink,
-				struct nfsd_net, nfsd_reply_cache_shrinker);
+	struct nfsd_net *nn = shrink->private_data;
 	unsigned long freed = 0;
 	LIST_HEAD(dispose);
 	unsigned int i;
_

Patches currently in -mm which might be from zhengqi.arch@bytedance.com 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