Now there are no readers of shrinker_rwsem, so we can simply replace it
with mutex lock.
Signed-off-by: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx>
---
drivers/md/dm-cache-metadata.c | 2 +-
fs/super.c | 2 +-
mm/shrinker.c | 16 ++++++++--------
mm/shrinker_debug.c | 14 +++++++-------
4 files changed, 17 insertions(+), 17 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 outside of
* cmd root_lock to avoid ABBA deadlock that would result (due to life-cycle 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 = dm_block_manager_create(cmd->bdev, DM_CACHE_METADATA_BLOCK_SIZE << SECTOR_SHIFT,
CACHE_MAX_CONCURRENT_LOCKS);
diff --git a/fs/super.c b/fs/super.c
index 04643fd80886..602cf54eb7da 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -54,7 +54,7 @@ static char *sb_writers_name[SB_FREEZE_LEVELS] = {
* One thing we have to be careful of with a per-sb shrinker is that we don't
* drop the last active reference to the superblock from within the shrinker.
* 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 90c045620fe3..5c4546d2c234 100644
--- a/mm/shrinker.c
+++ b/mm/shrinker.c
@@ -7,7 +7,7 @@
#include <trace/events/vmscan.h>
LIST_HEAD(shrinker_list);
-DECLARE_RWSEM(shrinker_rwsem);
+DEFINE_MUTEX(shrinker_mutex);
DEFINE_SPINLOCK(shrinker_lock);
#ifdef CONFIG_MEMCG
@@ -80,7 +80,7 @@ int alloc_shrinker_info(struct mem_cgroup *memcg)
int nid, ret = 0;
int array_size = 0;
- down_write(&shrinker_rwsem);
+ mutex_lock(&shrinker_mutex);
array_size = shrinker_unit_size(shrinker_nr_max);
for_each_node(nid) {
info = 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);
return ret;
@@ -104,7 +104,7 @@ static struct shrinker_info *shrinker_info_protected(struct mem_cgroup *memcg,
int nid)
{
return rcu_dereference_protected(memcg->nodeinfo[nid]->shrinker_info,
- lockdep_is_held(&shrinker_rwsem));
+ lockdep_is_held(&shrinker_mutex));
}
static struct shrinker_info *shrinker_info_rcu(struct mem_cgroup *memcg,
@@ -158,7 +158,7 @@ static int expand_shrinker_info(int new_id)
int new_size, old_size = 0;
struct mem_cgroup *memcg;
- down_write(&shrinker_rwsem);
+ mutex_lock(&shrinker_mutex);
if (!root_mem_cgroup)
goto out;
@@ -179,7 +179,7 @@ static int expand_shrinker_info(int new_id)
if (!ret)
shrinker_nr_max = new_nr_max;
- up_write(&shrinker_rwsem);
+ mutex_unlock(&shrinker_mutex);
return ret;
}
@@ -303,7 +303,7 @@ void reparent_shrinker_deferred(struct mem_cgroup *memcg)
parent = root_mem_cgroup;
/* Prevent from concurrent shrinker_info expand */
- down_write(&shrinker_rwsem);
+ mutex_lock(&shrinker_mutex);
for_each_node(nid) {
child_info = shrinker_info_protected(memcg, nid);
parent_info = shrinker_info_protected(parent, nid);
@@ -316,7 +316,7 @@ void reparent_shrinker_deferred(struct mem_cgroup *memcg)
}
}
}
- up_write(&shrinker_rwsem);
+ mutex_unlock(&shrinker_mutex);
}
#else
static int shrinker_memcg_alloc(struct shrinker *shrinker)
diff --git a/mm/shrinker_debug.c b/mm/shrinker_debug.c
index badda35464c3..44b620b1919d 100644
--- a/mm/shrinker_debug.c
+++ b/mm/shrinker_debug.c
@@ -8,7 +8,7 @@
#include <linux/rculist.h>
/* defined in vmscan.c */
-extern struct rw_semaphore shrinker_rwsem;
+extern struct mutex shrinker_mutex;
extern struct list_head shrinker_list;
static DEFINE_IDA(shrinker_debugfs_ida);
@@ -168,7 +168,7 @@ int shrinker_debugfs_add(struct shrinker *shrinker)
if (!shrinker_debugfs_root)
return 0;
- down_write(&shrinker_rwsem);
+ mutex_lock(&shrinker_mutex);
if (shrinker->debugfs_entry)
goto fail;
@@ -196,7 +196,7 @@ int shrinker_debugfs_add(struct shrinker *shrinker)
&shrinker_debugfs_scan_fops);
fail:
- up_write(&shrinker_rwsem);
+ mutex_unlock(&shrinker_mutex);
return ret;
}
@@ -215,7 +215,7 @@ int shrinker_debugfs_rename(struct shrinker *shrinker, const char *fmt, ...)
if (!new)
return -ENOMEM;
- down_write(&shrinker_rwsem);
+ mutex_lock(&shrinker_mutex);
old = shrinker->name;
shrinker->name = new;
@@ -233,7 +233,7 @@ int shrinker_debugfs_rename(struct shrinker *shrinker, const char *fmt, ...)
shrinker->debugfs_entry = entry;
}
- up_write(&shrinker_rwsem);
+ mutex_unlock(&shrinker_mutex);
kfree_const(old);
@@ -246,7 +246,7 @@ struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker,
{
struct dentry *entry = shrinker->debugfs_entry;
- down_write(&shrinker_rwsem);
+ mutex_lock(&shrinker_mutex);
kfree_const(shrinker->name);
shrinker->name = NULL;
@@ -257,7 +257,7 @@ struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker,
*/
smp_wmb();
shrinker->debugfs_entry = NULL;
- up_write(&shrinker_rwsem);
+ mutex_unlock(&shrinker_mutex);
return entry;
}
--
2.30.2
