From 55fa6091d83160ca772fc37cebae45d42695a708 Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Tue, 22 Mar 2011 22:23:40 +1100 Subject: fs: move i_sb_list out from under inode_lock Protect the per-sb inode list with a new global lock inode_sb_list_lock and use it to protect the list manipulations and traversals. This lock replaces the inode_lock as the inodes on the list can be validity checked while holding the inode->i_lock and hence the inode_lock is no longer needed to protect the list. Signed-off-by: Dave Chinner Signed-off-by: Al Viro --- fs/inode.c | 43 +++++++++++++++++++++++-------------------- 1 file changed, 23 insertions(+), 20 deletions(-) (limited to 'fs/inode.c') diff --git a/fs/inode.c b/fs/inode.c index 389f5a247599..785b1ab23ff0 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -34,10 +34,15 @@ * inode->i_state, inode->i_hash, __iget() * inode_lru_lock protects: * inode_lru, inode->i_lru + * inode_sb_list_lock protects: + * sb->s_inodes, inode->i_sb_list * * Lock ordering: * inode_lock * inode->i_lock + * + * inode_sb_list_lock + * inode->i_lock * inode_lru_lock */ @@ -99,6 +104,8 @@ static struct hlist_head *inode_hashtable __read_mostly; */ DEFINE_SPINLOCK(inode_lock); +__cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_sb_list_lock); + /* * iprune_sem provides exclusion between the icache shrinking and the * umount path. @@ -378,26 +385,23 @@ static void inode_lru_list_del(struct inode *inode) spin_unlock(&inode_lru_lock); } -static inline void __inode_sb_list_add(struct inode *inode) -{ - list_add(&inode->i_sb_list, &inode->i_sb->s_inodes); -} - /** * inode_sb_list_add - add inode to the superblock list of inodes * @inode: inode to add */ void inode_sb_list_add(struct inode *inode) { - spin_lock(&inode_lock); - __inode_sb_list_add(inode); - spin_unlock(&inode_lock); + spin_lock(&inode_sb_list_lock); + list_add(&inode->i_sb_list, &inode->i_sb->s_inodes); + spin_unlock(&inode_sb_list_lock); } EXPORT_SYMBOL_GPL(inode_sb_list_add); -static inline void __inode_sb_list_del(struct inode *inode) +static inline void inode_sb_list_del(struct inode *inode) { + spin_lock(&inode_sb_list_lock); list_del_init(&inode->i_sb_list); + spin_unlock(&inode_sb_list_lock); } static unsigned long hash(struct super_block *sb, unsigned long hashval) @@ -481,9 +485,10 @@ static void evict(struct inode *inode) spin_lock(&inode_lock); list_del_init(&inode->i_wb_list); - __inode_sb_list_del(inode); spin_unlock(&inode_lock); + inode_sb_list_del(inode); + if (op->evict_inode) { op->evict_inode(inode); } else { @@ -539,7 +544,7 @@ void evict_inodes(struct super_block *sb) struct inode *inode, *next; LIST_HEAD(dispose); - spin_lock(&inode_lock); + spin_lock(&inode_sb_list_lock); list_for_each_entry_safe(inode, next, &sb->s_inodes, i_sb_list) { if (atomic_read(&inode->i_count)) continue; @@ -555,7 +560,7 @@ void evict_inodes(struct super_block *sb) spin_unlock(&inode->i_lock); list_add(&inode->i_lru, &dispose); } - spin_unlock(&inode_lock); + spin_unlock(&inode_sb_list_lock); dispose_list(&dispose); @@ -584,7 +589,7 @@ int invalidate_inodes(struct super_block *sb, bool kill_dirty) struct inode *inode, *next; LIST_HEAD(dispose); - spin_lock(&inode_lock); + spin_lock(&inode_sb_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)) { @@ -607,7 +612,7 @@ int invalidate_inodes(struct super_block *sb, bool kill_dirty) spin_unlock(&inode->i_lock); list_add(&inode->i_lru, &dispose); } - spin_unlock(&inode_lock); + spin_unlock(&inode_sb_list_lock); dispose_list(&dispose); @@ -867,16 +872,14 @@ struct inode *new_inode(struct super_block *sb) { struct inode *inode; - spin_lock_prefetch(&inode_lock); + spin_lock_prefetch(&inode_sb_list_lock); inode = alloc_inode(sb); if (inode) { - spin_lock(&inode_lock); spin_lock(&inode->i_lock); inode->i_state = 0; spin_unlock(&inode->i_lock); - __inode_sb_list_add(inode); - spin_unlock(&inode_lock); + inode_sb_list_add(inode); } return inode; } @@ -945,7 +948,7 @@ static struct inode *get_new_inode(struct super_block *sb, inode->i_state = I_NEW; hlist_add_head(&inode->i_hash, head); spin_unlock(&inode->i_lock); - __inode_sb_list_add(inode); + inode_sb_list_add(inode); spin_unlock(&inode_lock); /* Return the locked inode with I_NEW set, the @@ -994,7 +997,7 @@ static struct inode *get_new_inode_fast(struct super_block *sb, inode->i_state = I_NEW; hlist_add_head(&inode->i_hash, head); spin_unlock(&inode->i_lock); - __inode_sb_list_add(inode); + inode_sb_list_add(inode); spin_unlock(&inode_lock); /* Return the locked inode with I_NEW set, the -- cgit v1.2.3-55-g7522