From: Dave Chinner Date: Wed, 4 Mar 2015 17:37:22 +0000 (-0500) Subject: inode: convert inode_sb_list_lock to per-sb X-Git-Tag: firefly_0821_release~176^2~1129^2~4^2~3 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=74278da9f70d84d715601fe794567a6d2bfdf078;p=firefly-linux-kernel-4.4.55.git 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 Signed-off-by: Josef Bacik Reviewed-by: Jan Kara Reviewed-by: Christoph Hellwig Tested-by: Dave Chinner --- diff --git a/fs/block_dev.c b/fs/block_dev.c index 198243717da5..33b813e04f79 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -1769,7 +1769,7 @@ void iterate_bdevs(void (*func)(struct block_device *, void *), void *arg) { struct inode *inode, *old_inode = NULL; - spin_lock(&inode_sb_list_lock); + spin_lock(&blockdev_superblock->s_inode_list_lock); list_for_each_entry(inode, &blockdev_superblock->s_inodes, i_sb_list) { struct address_space *mapping = inode->i_mapping; @@ -1781,13 +1781,13 @@ void iterate_bdevs(void (*func)(struct block_device *, void *), void *arg) } __iget(inode); spin_unlock(&inode->i_lock); - spin_unlock(&inode_sb_list_lock); + spin_unlock(&blockdev_superblock->s_inode_list_lock); /* * We hold a reference to 'inode' so it couldn't have been * removed from s_inodes list while we dropped the - * inode_sb_list_lock. We cannot iput the inode now as we can + * s_inode_list_lock We cannot iput the inode now as we can * be holding the last reference and we cannot iput it under - * inode_sb_list_lock. So we keep the reference and iput it + * s_inode_list_lock. So we keep the reference and iput it * later. */ iput(old_inode); @@ -1795,8 +1795,8 @@ void iterate_bdevs(void (*func)(struct block_device *, void *), void *arg) func(I_BDEV(inode), arg); - spin_lock(&inode_sb_list_lock); + spin_lock(&blockdev_superblock->s_inode_list_lock); } - spin_unlock(&inode_sb_list_lock); + spin_unlock(&blockdev_superblock->s_inode_list_lock); iput(old_inode); } diff --git a/fs/drop_caches.c b/fs/drop_caches.c index 5718cb9f7273..d72d52b90433 100644 --- a/fs/drop_caches.c +++ b/fs/drop_caches.c @@ -17,7 +17,7 @@ static void drop_pagecache_sb(struct super_block *sb, void *unused) { struct inode *inode, *toput_inode = NULL; - spin_lock(&inode_sb_list_lock); + spin_lock(&sb->s_inode_list_lock); list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { spin_lock(&inode->i_lock); if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) || @@ -27,13 +27,15 @@ static void drop_pagecache_sb(struct super_block *sb, void *unused) } __iget(inode); spin_unlock(&inode->i_lock); - spin_unlock(&inode_sb_list_lock); + spin_unlock(&sb->s_inode_list_lock); + invalidate_mapping_pages(inode->i_mapping, 0, -1); iput(toput_inode); toput_inode = inode; - spin_lock(&inode_sb_list_lock); + + spin_lock(&sb->s_inode_list_lock); } - spin_unlock(&inode_sb_list_lock); + spin_unlock(&sb->s_inode_list_lock); iput(toput_inode); } diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index d98e37bbf417..f45bf876579f 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -2124,7 +2124,7 @@ static void wait_sb_inodes(struct super_block *sb) */ WARN_ON(!rwsem_is_locked(&sb->s_umount)); - spin_lock(&inode_sb_list_lock); + spin_lock(&sb->s_inode_list_lock); /* * Data integrity sync. Must wait for all pages under writeback, @@ -2144,14 +2144,14 @@ static void wait_sb_inodes(struct super_block *sb) } __iget(inode); spin_unlock(&inode->i_lock); - spin_unlock(&inode_sb_list_lock); + spin_unlock(&sb->s_inode_list_lock); /* * We hold a reference to 'inode' so it couldn't have been * removed from s_inodes list while we dropped the - * inode_sb_list_lock. We cannot iput the inode now as we can + * s_inode_list_lock. We cannot iput the inode now as we can * be holding the last reference and we cannot iput it under - * inode_sb_list_lock. So we keep the reference and iput it + * s_inode_list_lock. So we keep the reference and iput it * later. */ iput(old_inode); @@ -2161,9 +2161,9 @@ static void wait_sb_inodes(struct super_block *sb) cond_resched(); - spin_lock(&inode_sb_list_lock); + spin_lock(&sb->s_inode_list_lock); } - spin_unlock(&inode_sb_list_lock); + spin_unlock(&sb->s_inode_list_lock); iput(old_inode); } diff --git a/fs/inode.c b/fs/inode.c index d30640f7a193..a2de294f6b77 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 unsigned int i_hash_shift __read_mostly; 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 @@ static void inode_lru_list_del(struct inode *inode) */ 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 @@ void evict_inodes(struct super_block *sb) 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 @@ void evict_inodes(struct super_block *sb) 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 @@ int invalidate_inodes(struct super_block *sb, bool kill_dirty) 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 @@ int invalidate_inodes(struct super_block *sb, bool kill_dirty) 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 *new_inode(struct super_block *sb) { 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) diff --git a/fs/internal.h b/fs/internal.h index 4d5af583ab03..ee1209c54eb1 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -112,7 +112,6 @@ extern int vfs_open(const struct path *, struct file *, const struct cred *); /* * inode.c */ -extern spinlock_t inode_sb_list_lock; extern long prune_icache_sb(struct super_block *sb, struct shrink_control *sc); extern void inode_add_lru(struct inode *inode); diff --git a/fs/notify/inode_mark.c b/fs/notify/inode_mark.c index 3daf513ee99e..a4e1a8f6c329 100644 --- a/fs/notify/inode_mark.c +++ b/fs/notify/inode_mark.c @@ -163,17 +163,17 @@ int fsnotify_add_inode_mark(struct fsnotify_mark *mark, /** * fsnotify_unmount_inodes - an sb is unmounting. handle any watched inodes. - * @list: list of inodes being unmounted (sb->s_inodes) + * @sb: superblock being unmounted. * * Called during unmount with no locks held, so needs to be safe against - * concurrent modifiers. We temporarily drop inode_sb_list_lock and CAN block. + * concurrent modifiers. We temporarily drop sb->s_inode_list_lock and CAN block. */ -void fsnotify_unmount_inodes(struct list_head *list) +void fsnotify_unmount_inodes(struct super_block *sb) { struct inode *inode, *next_i, *need_iput = NULL; - spin_lock(&inode_sb_list_lock); - list_for_each_entry_safe(inode, next_i, list, i_sb_list) { + spin_lock(&sb->s_inode_list_lock); + list_for_each_entry_safe(inode, next_i, &sb->s_inodes, i_sb_list) { struct inode *need_iput_tmp; /* @@ -209,7 +209,7 @@ void fsnotify_unmount_inodes(struct list_head *list) spin_unlock(&inode->i_lock); /* In case the dropping of a reference would nuke next_i. */ - while (&next_i->i_sb_list != list) { + while (&next_i->i_sb_list != &sb->s_inodes) { spin_lock(&next_i->i_lock); if (!(next_i->i_state & (I_FREEING | I_WILL_FREE)) && atomic_read(&next_i->i_count)) { @@ -224,12 +224,12 @@ void fsnotify_unmount_inodes(struct list_head *list) } /* - * We can safely drop inode_sb_list_lock here because either + * We can safely drop s_inode_list_lock here because either * we actually hold references on both inode and next_i or * end of list. Also no new inodes will be added since the * umount has begun. */ - spin_unlock(&inode_sb_list_lock); + spin_unlock(&sb->s_inode_list_lock); if (need_iput_tmp) iput(need_iput_tmp); @@ -241,7 +241,7 @@ void fsnotify_unmount_inodes(struct list_head *list) iput(inode); - spin_lock(&inode_sb_list_lock); + spin_lock(&sb->s_inode_list_lock); } - spin_unlock(&inode_sb_list_lock); + spin_unlock(&sb->s_inode_list_lock); } diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c index 20d1f74561cf..2863ec6cbadf 100644 --- a/fs/quota/dquot.c +++ b/fs/quota/dquot.c @@ -923,7 +923,7 @@ static void add_dquot_ref(struct super_block *sb, int type) int reserved = 0; #endif - spin_lock(&inode_sb_list_lock); + spin_lock(&sb->s_inode_list_lock); list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { spin_lock(&inode->i_lock); if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) || @@ -934,7 +934,7 @@ static void add_dquot_ref(struct super_block *sb, int type) } __iget(inode); spin_unlock(&inode->i_lock); - spin_unlock(&inode_sb_list_lock); + spin_unlock(&sb->s_inode_list_lock); #ifdef CONFIG_QUOTA_DEBUG if (unlikely(inode_get_rsv_space(inode) > 0)) @@ -946,15 +946,15 @@ static void add_dquot_ref(struct super_block *sb, int type) /* * We hold a reference to 'inode' so it couldn't have been * removed from s_inodes list while we dropped the - * inode_sb_list_lock We cannot iput the inode now as we can be + * s_inode_list_lock. We cannot iput the inode now as we can be * holding the last reference and we cannot iput it under - * inode_sb_list_lock. So we keep the reference and iput it + * s_inode_list_lock. So we keep the reference and iput it * later. */ old_inode = inode; - spin_lock(&inode_sb_list_lock); + spin_lock(&sb->s_inode_list_lock); } - spin_unlock(&inode_sb_list_lock); + spin_unlock(&sb->s_inode_list_lock); iput(old_inode); #ifdef CONFIG_QUOTA_DEBUG @@ -1023,7 +1023,7 @@ static void remove_dquot_ref(struct super_block *sb, int type, struct inode *inode; int reserved = 0; - spin_lock(&inode_sb_list_lock); + spin_lock(&sb->s_inode_list_lock); list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { /* * We have to scan also I_NEW inodes because they can already @@ -1039,7 +1039,7 @@ static void remove_dquot_ref(struct super_block *sb, int type, } spin_unlock(&dq_data_lock); } - spin_unlock(&inode_sb_list_lock); + spin_unlock(&sb->s_inode_list_lock); #ifdef CONFIG_QUOTA_DEBUG if (reserved) { printk(KERN_WARNING "VFS (%s): Writes happened after quota" diff --git a/fs/super.c b/fs/super.c index b61372354f2b..c808183554a2 100644 --- a/fs/super.c +++ b/fs/super.c @@ -191,6 +191,7 @@ static struct super_block *alloc_super(struct file_system_type *type, int flags) INIT_HLIST_NODE(&s->s_instances); INIT_HLIST_BL_HEAD(&s->s_anon); INIT_LIST_HEAD(&s->s_inodes); + spin_lock_init(&s->s_inode_list_lock); if (list_lru_init_memcg(&s->s_dentry_lru)) goto fail; @@ -399,7 +400,7 @@ void generic_shutdown_super(struct super_block *sb) sync_filesystem(sb); sb->s_flags &= ~MS_ACTIVE; - fsnotify_unmount_inodes(&sb->s_inodes); + fsnotify_unmount_inodes(sb); evict_inodes(sb); diff --git a/include/linux/fs.h b/include/linux/fs.h index 4a40fa843040..09bbd38485f9 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1309,7 +1309,6 @@ struct super_block { #endif const struct xattr_handler **s_xattr; - struct list_head s_inodes; /* all inodes */ struct hlist_bl_head s_anon; /* anonymous dentries for (nfs) exporting */ struct list_head s_mounts; /* list of mounts; _not_ for fs use */ struct block_device *s_bdev; @@ -1380,6 +1379,10 @@ struct super_block { * Indicates how deep in a filesystem stack this SB is */ int s_stack_depth; + + /* s_inode_list_lock protects s_inodes */ + spinlock_t s_inode_list_lock ____cacheline_aligned_in_smp; + struct list_head s_inodes; /* all inodes */ }; extern struct timespec current_fs_time(struct super_block *sb); diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h index 65a517dd32f7..0390ee69c439 100644 --- a/include/linux/fsnotify_backend.h +++ b/include/linux/fsnotify_backend.h @@ -357,7 +357,7 @@ extern void fsnotify_clear_marks_by_group_flags(struct fsnotify_group *group, un extern void fsnotify_clear_marks_by_group(struct fsnotify_group *group); extern void fsnotify_get_mark(struct fsnotify_mark *mark); extern void fsnotify_put_mark(struct fsnotify_mark *mark); -extern void fsnotify_unmount_inodes(struct list_head *list); +extern void fsnotify_unmount_inodes(struct super_block *sb); /* put here because inotify does some weird stuff when destroying watches */ extern void fsnotify_init_event(struct fsnotify_event *event, @@ -393,7 +393,7 @@ static inline u32 fsnotify_get_cookie(void) return 0; } -static inline void fsnotify_unmount_inodes(struct list_head *list) +static inline void fsnotify_unmount_inodes(struct super_block *sb) {} #endif /* CONFIG_FSNOTIFY */