inode: convert inode_sb_list_lock to per-sb
The process of reducing contention on per-superblock inode lists
starts with moving the locking to match the per-superblock inode
list. This takes the global lock out of the picture and reduces the
contention problems to within a single filesystem. This doesn't get
rid of contention as the locks still have global CPU scope, but it
does isolate operations on different superblocks form each other.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Dave Chinner <dchinner@redhat.com>
diff --git a/fs/inode.c b/fs/inode.c
index d30640f..a2de294 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -28,8 +28,8 @@
* inode->i_state, inode->i_hash, __iget()
* Inode LRU list locks protect:
* inode->i_sb->s_inode_lru, inode->i_lru
- * inode_sb_list_lock protects:
- * sb->s_inodes, inode->i_sb_list
+ * inode->i_sb->s_inode_list_lock protects:
+ * inode->i_sb->s_inodes, inode->i_sb_list
* bdi->wb.list_lock protects:
* bdi->wb.b_{dirty,io,more_io,dirty_time}, inode->i_wb_list
* inode_hash_lock protects:
@@ -37,7 +37,7 @@
*
* Lock ordering:
*
- * inode_sb_list_lock
+ * inode->i_sb->s_inode_list_lock
* inode->i_lock
* Inode LRU list locks
*
@@ -45,7 +45,7 @@
* inode->i_lock
*
* inode_hash_lock
- * inode_sb_list_lock
+ * inode->i_sb->s_inode_list_lock
* inode->i_lock
*
* iunique_lock
@@ -57,8 +57,6 @@
static struct hlist_head *inode_hashtable __read_mostly;
static __cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_hash_lock);
-__cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_sb_list_lock);
-
/*
* Empty aops. Can be used for the cases where the user does not
* define any of the address_space operations.
@@ -426,18 +424,18 @@
*/
void inode_sb_list_add(struct inode *inode)
{
- spin_lock(&inode_sb_list_lock);
+ spin_lock(&inode->i_sb->s_inode_list_lock);
list_add(&inode->i_sb_list, &inode->i_sb->s_inodes);
- spin_unlock(&inode_sb_list_lock);
+ spin_unlock(&inode->i_sb->s_inode_list_lock);
}
EXPORT_SYMBOL_GPL(inode_sb_list_add);
static inline void inode_sb_list_del(struct inode *inode)
{
if (!list_empty(&inode->i_sb_list)) {
- spin_lock(&inode_sb_list_lock);
+ spin_lock(&inode->i_sb->s_inode_list_lock);
list_del_init(&inode->i_sb_list);
- spin_unlock(&inode_sb_list_lock);
+ spin_unlock(&inode->i_sb->s_inode_list_lock);
}
}
@@ -594,7 +592,7 @@
struct inode *inode, *next;
LIST_HEAD(dispose);
- spin_lock(&inode_sb_list_lock);
+ spin_lock(&sb->s_inode_list_lock);
list_for_each_entry_safe(inode, next, &sb->s_inodes, i_sb_list) {
if (atomic_read(&inode->i_count))
continue;
@@ -610,7 +608,7 @@
spin_unlock(&inode->i_lock);
list_add(&inode->i_lru, &dispose);
}
- spin_unlock(&inode_sb_list_lock);
+ spin_unlock(&sb->s_inode_list_lock);
dispose_list(&dispose);
}
@@ -631,7 +629,7 @@
struct inode *inode, *next;
LIST_HEAD(dispose);
- spin_lock(&inode_sb_list_lock);
+ spin_lock(&sb->s_inode_list_lock);
list_for_each_entry_safe(inode, next, &sb->s_inodes, i_sb_list) {
spin_lock(&inode->i_lock);
if (inode->i_state & (I_NEW | I_FREEING | I_WILL_FREE)) {
@@ -654,7 +652,7 @@
spin_unlock(&inode->i_lock);
list_add(&inode->i_lru, &dispose);
}
- spin_unlock(&inode_sb_list_lock);
+ spin_unlock(&sb->s_inode_list_lock);
dispose_list(&dispose);
@@ -890,7 +888,7 @@
{
struct inode *inode;
- spin_lock_prefetch(&inode_sb_list_lock);
+ spin_lock_prefetch(&sb->s_inode_list_lock);
inode = new_inode_pseudo(sb);
if (inode)
