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Signed-off-by: Qi Zheng --- drivers/md/dm-cache-metadata.c | 2 +- fs/super.c | 2 +- mm/shrinker.c | 28 ++++++++++++++-------------- mm/shrinker_debug.c | 14 +++++++------- 4 files changed, 23 insertions(+), 23 deletions(-) diff --git a/drivers/md/dm-cache-metadata.c b/drivers/md/dm-cache-metadata.c index acffed750e3e..9e0c69958587 100644 --- a/drivers/md/dm-cache-metadata.c +++ b/drivers/md/dm-cache-metadata.c @@ -1828,7 +1828,7 @@ int dm_cache_metadata_abort(struct dm_cache_metadata = *cmd) * Replacement block manager (new_bm) is created and old_bm destroyed out= side of * cmd root_lock to avoid ABBA deadlock that would result (due to life-cy= cle of * shrinker associated with the block manager's bufio client vs cmd root_= lock). - * - must take shrinker_rwsem without holding cmd->root_lock + * - must take shrinker_mutex without holding cmd->root_lock */ new_bm =3D dm_block_manager_create(cmd->bdev, DM_CACHE_METADATA_BLOCK_SIZ= E << SECTOR_SHIFT, CACHE_MAX_CONCURRENT_LOCKS); diff --git a/fs/super.c b/fs/super.c index adadf6689611..816a22a5cad1 100644 --- a/fs/super.c +++ b/fs/super.c @@ -178,7 +178,7 @@ static void super_wake(struct super_block *sb, unsigned= int flag) * One thing we have to be careful of with a per-sb shrinker is that we do= n't * drop the last active reference to the superblock from within the shrink= er. * If that happens we could trigger unregistering the shrinker from within= the - * shrinker path and that leads to deadlock on the shrinker_rwsem. Hence we + * shrinker path and that leads to deadlock on the shrinker_mutex. Hence we * take a passive reference to the superblock to avoid this from occurring. */ static unsigned long super_cache_scan(struct shrinker *shrink, diff --git a/mm/shrinker.c b/mm/shrinker.c index 471c07d75c4a..2c44c3d7afe9 100644 --- a/mm/shrinker.c +++ b/mm/shrinker.c @@ -8,7 +8,7 @@ #include "internal.h" =20 LIST_HEAD(shrinker_list); -DECLARE_RWSEM(shrinker_rwsem); +DEFINE_MUTEX(shrinker_mutex); =20 #ifdef CONFIG_MEMCG static int shrinker_nr_max; @@ -80,7 +80,7 @@ int alloc_shrinker_info(struct mem_cgroup *memcg) int nid, ret =3D 0; int array_size =3D 0; =20 - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); array_size =3D shrinker_unit_size(shrinker_nr_max); for_each_node(nid) { info =3D kvzalloc_node(sizeof(*info) + array_size, GFP_KERNEL, nid); @@ -91,7 +91,7 @@ int alloc_shrinker_info(struct mem_cgroup *memcg) goto err; rcu_assign_pointer(memcg->nodeinfo[nid]->shrinker_info, info); } - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); =20 return ret; =20 @@ -104,7 +104,7 @@ static struct shrinker_info *shrinker_info_protected(st= ruct mem_cgroup *memcg, int nid) { return rcu_dereference_protected(memcg->nodeinfo[nid]->shrinker_info, - lockdep_is_held(&shrinker_rwsem)); + lockdep_is_held(&shrinker_mutex)); } =20 static int expand_one_shrinker_info(struct mem_cgroup *memcg, int new_size, @@ -154,7 +154,7 @@ static int expand_shrinker_info(int new_id) if (!root_mem_cgroup) goto out; =20 - lockdep_assert_held(&shrinker_rwsem); + lockdep_assert_held(&shrinker_mutex); =20 new_size =3D shrinker_unit_size(new_nr_max); old_size =3D shrinker_unit_size(shrinker_nr_max); @@ -217,7 +217,7 @@ static int shrinker_memcg_alloc(struct shrinker *shrink= er) if (mem_cgroup_disabled()) return -ENOSYS; =20 - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); id =3D idr_alloc(&shrinker_idr, shrinker, 0, 0, GFP_KERNEL); if (id < 0) goto unlock; @@ -231,7 +231,7 @@ static int shrinker_memcg_alloc(struct shrinker *shrink= er) shrinker->id =3D id; ret =3D 0; unlock: - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); return ret; } =20 @@ -241,7 +241,7 @@ static void shrinker_memcg_remove(struct shrinker *shri= nker) =20 BUG_ON(id < 0); =20 - lockdep_assert_held(&shrinker_rwsem); + lockdep_assert_held(&shrinker_mutex); =20 idr_remove(&shrinker_idr, id); } @@ -292,7 +292,7 @@ void reparent_shrinker_deferred(struct mem_cgroup *memc= g) parent =3D root_mem_cgroup; =20 /* Prevent from concurrent shrinker_info expand */ - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); for_each_node(nid) { child_info =3D shrinker_info_protected(memcg, nid); parent_info =3D shrinker_info_protected(parent, nid); @@ -305,7 +305,7 @@ void reparent_shrinker_deferred(struct mem_cgroup *memc= g) } } } - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); } #else static int shrinker_memcg_alloc(struct shrinker *shrinker) @@ -735,11 +735,11 @@ void shrinker_register(struct shrinker *shrinker) return; } =20 - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); list_add_tail_rcu(&shrinker->list, &shrinker_list); shrinker->flags |=3D SHRINKER_REGISTERED; shrinker_debugfs_add(shrinker); - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); =20 init_completion(&shrinker->done); /* @@ -779,7 +779,7 @@ void shrinker_free(struct shrinker *shrinker) wait_for_completion(&shrinker->done); } =20 - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); if (shrinker->flags & SHRINKER_REGISTERED) { /* * Now we can safely remove it from the shrinker_list and then @@ -794,7 +794,7 @@ void shrinker_free(struct shrinker *shrinker) =20 if (shrinker->flags & SHRINKER_MEMCG_AWARE) shrinker_memcg_remove(shrinker); - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); =20 if (debugfs_entry) shrinker_debugfs_remove(debugfs_entry, debugfs_id); diff --git a/mm/shrinker_debug.c b/mm/shrinker_debug.c index 38452f539f40..c80fd124f605 100644 --- a/mm/shrinker_debug.c +++ b/mm/shrinker_debug.c @@ -9,7 +9,7 @@ #include "internal.h" =20 /* defined in vmscan.c */ -extern struct rw_semaphore shrinker_rwsem; +extern struct mutex shrinker_mutex; extern struct list_head shrinker_list; =20 static DEFINE_IDA(shrinker_debugfs_ida); @@ -165,7 +165,7 @@ int shrinker_debugfs_add(struct shrinker *shrinker) char buf[128]; int id; =20 - lockdep_assert_held(&shrinker_rwsem); + lockdep_assert_held(&shrinker_mutex); =20 /* debugfs isn't initialized yet, add debugfs entries later. */ if (!shrinker_debugfs_root) @@ -222,7 +222,7 @@ int shrinker_debugfs_rename(struct shrinker *shrinker, = const char *fmt, ...) if (!new) return -ENOMEM; =20 - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); =20 old =3D shrinker->name; shrinker->name =3D new; @@ -240,7 +240,7 @@ int shrinker_debugfs_rename(struct shrinker *shrinker, = const char *fmt, ...) shrinker->debugfs_entry =3D entry; } =20 - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); =20 kfree_const(old); =20 @@ -253,7 +253,7 @@ struct dentry *shrinker_debugfs_detach(struct shrinker = *shrinker, { struct dentry *entry =3D shrinker->debugfs_entry; =20 - lockdep_assert_held(&shrinker_rwsem); + lockdep_assert_held(&shrinker_mutex); =20 shrinker_debugfs_name_free(shrinker); =20 @@ -281,14 +281,14 @@ static int __init shrinker_debugfs_init(void) shrinker_debugfs_root =3D dentry; =20 /* Create debugfs entries for shrinkers registered at boot */ - down_write(&shrinker_rwsem); + mutex_lock(&shrinker_mutex); list_for_each_entry(shrinker, &shrinker_list, list) if (!shrinker->debugfs_entry) { ret =3D shrinker_debugfs_add(shrinker); if (ret) break; } - up_write(&shrinker_rwsem); + mutex_unlock(&shrinker_mutex); =20 return ret; } --=20 2.30.2