From: Dave Chinner <dchinner@xxxxxxxxxx>
The per-superblock inode list and lock is a bottleneck for systems
that cycle inodes in and out of cache concurrently. The global lock
is a limiting factor.
Most of the additions to the sb inode list occur on the CPU that
allocated the inode, and most of the removals occur during evict()
calls as a result of memory reclaim. Both of these events are local
to the node that the inode belongs to, so it maps to the per-node
lists that the list_lru uses.
There are several places where the inode list is walked. These can
be converted easily to use list_lru_walk() to do their work on each
inode on the list.
Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx>
---
fs/block_dev.c | 75 ++++++++++++---------
fs/drop_caches.c | 57 +++++++++++-----
fs/fs-writeback.c | 4 +-
fs/inode.c | 134 +++++++++++++++++++------------------
fs/notify/inode_mark.c | 111 +++++++++++++------------------
fs/quota/dquot.c | 174 ++++++++++++++++++++++++++++++++-----------------
fs/super.c | 9 ++-
include/linux/fs.h | 9 ++-
8 files changed, 327 insertions(+), 246 deletions(-)
diff --git a/fs/block_dev.c b/fs/block_dev.c
index bec0c26..b8ec2bd 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1665,38 +1665,55 @@ int __invalidate_device(struct block_device *bdev, bool kill_dirty)
}
EXPORT_SYMBOL(__invalidate_device);
-void iterate_bdevs(void (*func)(struct block_device *, void *), void *arg)
-{
- struct inode *inode, *old_inode = NULL;
+struct bdev_iter {
+ void (*func)(struct block_device *, void *);
+ void *arg;
+ struct inode *toput_inode;
+};
- 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;
+static enum lru_status
+bdev_iter_cb(struct list_head *item, spinlock_t *lock, void *cb_arg)
+{
+ struct bdev_iter *iter = cb_arg;
+ struct inode *inode = container_of(item, struct inode, i_sb_list);
- spin_lock(&inode->i_lock);
- if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW) ||
- mapping->nrpages == 0) {
- spin_unlock(&inode->i_lock);
- continue;
- }
- __iget(inode);
+ spin_lock(&inode->i_lock);
+ if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW) ||
+ inode->i_mapping->nrpages == 0) {
spin_unlock(&inode->i_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
- * s_inode_list_lock We cannot iput the inode now as we can
- * be holding the last reference and we cannot iput it under
- * s_inode_list_lock. So we keep the reference and iput it
- * later.
- */
- iput(old_inode);
- old_inode = inode;
+ return LRU_SKIP;
+ }
+ __iget(inode);
+ spin_unlock(&inode->i_lock);
+ spin_unlock(lock);
- func(I_BDEV(inode), arg);
+ iput(iter->toput_inode);
+ iter->toput_inode = inode;
- spin_lock(&blockdev_superblock->s_inode_list_lock);
- }
- spin_unlock(&blockdev_superblock->s_inode_list_lock);
- iput(old_inode);
+ iter->func(I_BDEV(inode), iter->arg);
+
+ /*
+ * Even though we have dropped the lock here, we can return LRU_SKIP as
+ * we have a reference to the current inode and so it's next pointer is
+ * guaranteed to be valid even though we dropped the list lock.
+ */
+ spin_lock(lock);
+ return LRU_SKIP;
+}
+
+/*
+ * iterate_bdevs - run a callback across all block devices
+ */
+void iterate_bdevs(void (*func)(struct block_device *, void *), void *arg)
+{
+ struct bdev_iter iter = {
+ .func = func,
+ .arg = arg,
+ };
+
+ list_lru_walk(&blockdev_superblock->s_inode_list, bdev_iter_cb, &iter,
+ ULONG_MAX);
+
+ /* the list walk doesn't release the last inode it sees! */
+ iput(iter.toput_inode);
}
diff --git a/fs/drop_caches.c b/fs/drop_caches.c
index f1be790..048a7d7 100644
--- a/fs/drop_caches.c
+++ b/fs/drop_caches.c
@@ -13,29 +13,50 @@
/* A global variable is a bit ugly, but it keeps the code simple */
int sysctl_drop_caches;
-static void drop_pagecache_sb(struct super_block *sb, void *unused)
+static enum lru_status
+drop_pagecache_inode(struct list_head *item, spinlock_t *lock, void *cb_arg)
{
- struct inode *inode, *toput_inode = NULL;
+ struct inode **toput_inode = cb_arg;
+ struct inode *inode = container_of(item, struct inode, i_sb_list);
- 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)) ||
- (inode->i_mapping->nrpages == 0)) {
- spin_unlock(&inode->i_lock);
- continue;
- }
- __iget(inode);
+ spin_lock(&inode->i_lock);
+ if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) ||
+ (inode->i_mapping->nrpages == 0)) {
spin_unlock(&inode->i_lock);
- spin_unlock(&sb->s_inode_list_lock);
+ return LRU_SKIP;
+ }
+ __iget(inode);
+ spin_unlock(&inode->i_lock);
+ spin_unlock(lock);
- invalidate_mapping_pages(inode->i_mapping, 0, -1);
- iput(toput_inode);
- toput_inode = inode;
+ iput(*toput_inode);
+ *toput_inode = inode;
- spin_lock(&sb->s_inode_list_lock);
- }
- spin_unlock(&sb->s_inode_list_lock);
+ invalidate_mapping_pages(inode->i_mapping, 0, -1);
+
+ /*
+ * Even though we have dropped the lock here, we can return LRU_SKIP as
+ * we have a reference to the current inode and so it's next pointer is
+ * guaranteed to be valid even though we dropped the list lock.
+ */
+ spin_lock(lock);
+ return LRU_SKIP;
+}
+
+
+/*
+ * This is a best effort scan, so we don't need to be absolutely sure we hit al
+ * inodes on the superblock. Hence a single pass is sufficient to catch them
+ * all.
+ */
+static void drop_pagecache_sb(struct super_block *sb, void *unused)
+{
+ struct inode *toput_inode = NULL;
+
+ list_lru_walk(&sb->s_inode_list, drop_pagecache_inode, &toput_inode,
+ ULONG_MAX);
+
+ /* the list walk doesn't release the last inode it sees! */
iput(toput_inode);
}
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 7c9bbf0..f2d91de 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -1337,9 +1337,9 @@ static void wait_sb_inodes(struct super_block *sb)
/*
* We hold a reference to 'inode' so it couldn't have been
* removed from s_inodes list while we dropped the
- * s_inode_list_lock. We cannot iput the inode now as we can
+ * wb.list_lock We cannot iput the inode now as we can
* be holding the last reference and we cannot iput it under
- * s_inode_list_lock. So we keep the reference and iput it
+ * wb.list_lock So we keep the reference and iput it
* later.
*/
iput(old_inode);
diff --git a/fs/inode.c b/fs/inode.c
index de62d2b..7eea591 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -27,8 +27,8 @@
* inode->i_state, inode->i_hash, __iget()
* Inode LRU list locks protect:
* inode->i_sb->s_inode_lru, inode->i_lru
- * inode->i_sb->s_inode_list_lock protects:
- * inode->i_sb->s_inodes, inode->i_sb_list
+ * Inode list locks protects:
+ * inode->i_sb->s_inode_list, inode->i_sb_list
* bdi->wb.list_lock protects:
* bdi->wb.b_{dirty,io,more_io}, inode->i_io_list
* inode_hash_lock protects:
@@ -36,7 +36,7 @@
*
* Lock ordering:
*
- * inode->i_sb->s_inode_list_lock
+ * Inode list lock
* inode->i_lock
* Inode LRU list locks
*
@@ -44,7 +44,7 @@
* inode->i_lock
*
* inode_hash_lock
- * inode->i_sb->s_inode_list_lock
+ * Inode list lock
* inode->i_lock
*
* iunique_lock
@@ -366,6 +366,7 @@ void inode_init_once(struct inode *inode)
INIT_LIST_HEAD(&inode->i_devices);
INIT_LIST_HEAD(&inode->i_io_list);
INIT_LIST_HEAD(&inode->i_wb_list);
+ INIT_LIST_HEAD(&inode->i_sb_list);
INIT_LIST_HEAD(&inode->i_lru);
address_space_init_once(&inode->i_data);
i_size_ordered_init(inode);
@@ -431,19 +432,13 @@ static void inode_lru_list_del(struct inode *inode)
*/
void inode_sb_list_add(struct inode *inode)
{
- spin_lock(&inode->i_sb->s_inode_list_lock);
- list_add(&inode->i_sb_list, &inode->i_sb->s_inodes);
- spin_unlock(&inode->i_sb->s_inode_list_lock);
+ list_lru_add(&inode->i_sb->s_inode_list, &inode->i_sb_list);
}
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->i_sb->s_inode_list_lock);
- list_del_init(&inode->i_sb_list);
- spin_unlock(&inode->i_sb->s_inode_list_lock);
- }
+ list_lru_del(&inode->i_sb->s_inode_list, &inode->i_sb_list);
}
static unsigned long hash(struct super_block *sb, unsigned long hashval)
@@ -585,6 +580,48 @@ static void dispose_list(struct list_head *head)
}
}
+static enum lru_status
+__evict_inodes_isolate(struct list_head *item, spinlock_t *lock, void *cb_arg,
+ bool kill_dirty)
+{
+ struct list_head *dispose = cb_arg;
+ struct inode *inode = container_of(item, struct inode, i_sb_list);
+
+ if (atomic_read(&inode->i_count))
+ return LRU_SKIP;
+
+ spin_lock(&inode->i_lock);
+ if (inode->i_state & (I_NEW | I_FREEING | I_WILL_FREE)) {
+ spin_unlock(&inode->i_lock);
+ return LRU_SKIP;
+ }
+
+ if ((inode->i_state & I_DIRTY) && !kill_dirty) {
+ spin_unlock(&inode->i_lock);
+ return LRU_SKIP;
+ }
+
+ inode->i_state |= I_FREEING;
+ inode_lru_list_del(inode);
+ list_add(&inode->i_lru, dispose);
+
+ list_del_init(&inode->i_sb_list);
+ spin_unlock(&inode->i_lock);
+ return LRU_REMOVED;
+}
+
+static enum lru_status
+evict_inodes_isolate(struct list_head *item, spinlock_t *lock, void *cb_arg)
+{
+ return __evict_inodes_isolate(item, lock, cb_arg, true);
+}
+
+static enum lru_status
+invalidate_inodes_isolate(struct list_head *item, spinlock_t *lock, void *cb_arg)
+{
+ return __evict_inodes_isolate(item, lock, cb_arg, false);
+}
+
/**
* evict_inodes - evict all evictable inodes for a superblock
* @sb: superblock to operate on
@@ -596,28 +633,15 @@ static void dispose_list(struct list_head *head)
*/
void evict_inodes(struct super_block *sb)
{
- struct inode *inode, *next;
- LIST_HEAD(dispose);
-
- 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;
-
- spin_lock(&inode->i_lock);
- if (inode->i_state & (I_NEW | I_FREEING | I_WILL_FREE)) {
- spin_unlock(&inode->i_lock);
- continue;
- }
+ long freed;
- inode->i_state |= I_FREEING;
- inode_lru_list_del(inode);
- spin_unlock(&inode->i_lock);
- list_add(&inode->i_lru, &dispose);
- }
- spin_unlock(&sb->s_inode_list_lock);
+ do {
+ LIST_HEAD(dispose);
- dispose_list(&dispose);
+ freed = list_lru_walk(&sb->s_inode_list, evict_inodes_isolate,
+ &dispose, ULONG_MAX);
+ dispose_list(&dispose);
+ } while (freed > 0);
}
/**
@@ -632,38 +656,24 @@ void evict_inodes(struct super_block *sb)
*/
int invalidate_inodes(struct super_block *sb, bool kill_dirty)
{
- int busy = 0;
- struct inode *inode, *next;
- LIST_HEAD(dispose);
+ list_lru_walk_cb isolate;
+ long freed;
- 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)) {
- spin_unlock(&inode->i_lock);
- continue;
- }
- if (inode->i_state & I_DIRTY && !kill_dirty) {
- spin_unlock(&inode->i_lock);
- busy = 1;
- continue;
- }
- if (atomic_read(&inode->i_count)) {
- spin_unlock(&inode->i_lock);
- busy = 1;
- continue;
- }
+ isolate = kill_dirty ? evict_inodes_isolate :invalidate_inodes_isolate;
- inode->i_state |= I_FREEING;
- inode_lru_list_del(inode);
- spin_unlock(&inode->i_lock);
- list_add(&inode->i_lru, &dispose);
- }
- spin_unlock(&sb->s_inode_list_lock);
+ do {
+ LIST_HEAD(dispose);
- dispose_list(&dispose);
+ freed = list_lru_walk(&sb->s_inode_list, isolate,
+ &dispose, ULONG_MAX);
+ dispose_list(&dispose);
+ } while (freed > 0);
- return busy;
+ /*
+ * if we skipped any inodes because we couldn't isolate them, tell the
+ * caller there are still active inodes.
+ */
+ return !!list_lru_count(&sb->s_inode_list);
}
/*
@@ -866,7 +876,7 @@ EXPORT_SYMBOL(get_next_ino);
* @sb: superblock
*
* Allocates a new inode for given superblock.
- * Inode wont be chained in superblock s_inodes list
+ * Inode wont be chained in superblock s_inode_list list
* This means :
* - fs can't be unmount
* - quotas, fsnotify, writeback can't work
@@ -900,8 +910,6 @@ struct inode *new_inode(struct super_block *sb)
{
struct inode *inode;
- spin_lock_prefetch(&sb->s_inode_list_lock);
-
inode = new_inode_pseudo(sb);
if (inode)
inode_sb_list_add(inode);
diff --git a/fs/notify/inode_mark.c b/fs/notify/inode_mark.c
index fac139a..2aef9e5 100644
--- a/fs/notify/inode_mark.c
+++ b/fs/notify/inode_mark.c
@@ -240,82 +240,59 @@ out:
return ret;
}
-/**
- * fsnotify_unmount_inodes - an sb is unmounting. handle any watched inodes.
- * @sb: superblock being unmounted.
- *
- * Called during unmount with no locks held, so needs to be safe against
- * concurrent modifiers. We temporarily drop sb->s_inode_list_lock and CAN block.
- */
-void fsnotify_unmount_inodes(struct super_block *sb)
+static enum lru_status
+fsnotify_unmount_inode(struct list_head *item, spinlock_t *lock, void *cb_arg)
{
- struct inode *inode, *next_i, *need_iput = NULL;
-
- 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;
-
- /*
- * We cannot __iget() an inode in state I_FREEING,
- * I_WILL_FREE, or I_NEW which is fine because by that point
- * the inode cannot have any associated watches.
- */
- spin_lock(&inode->i_lock);
- if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) {
- spin_unlock(&inode->i_lock);
- continue;
- }
+ struct inode **toput_inode = cb_arg;
+ struct inode *inode = container_of(item, struct inode, i_sb_list);
- /*
- * If i_count is zero, the inode cannot have any watches and
- * doing an __iget/iput with MS_ACTIVE clear would actually
- * evict all inodes with zero i_count from icache which is
- * unnecessarily violent and may in fact be illegal to do.
- */
- if (!atomic_read(&inode->i_count)) {
- spin_unlock(&inode->i_lock);
- continue;
- }
-
- need_iput_tmp = need_iput;
- need_iput = NULL;
+ /* New or being freed inodes cannot have any associated watches. */
+ spin_lock(&inode->i_lock);
+ if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) {
+ spin_unlock(&inode->i_lock);
+ return LRU_SKIP;
+ }
- /* In case fsnotify_inode_delete() drops a reference. */
- if (inode != need_iput_tmp)
- __iget(inode);
- else
- need_iput_tmp = NULL;
+ /* If i_count is zero, the inode cannot have any watches */
+ if (!atomic_read(&inode->i_count)) {
spin_unlock(&inode->i_lock);
+ return LRU_SKIP;
+ }
- /* In case the dropping of a reference would nuke next_i. */
- if ((&next_i->i_sb_list != &sb->s_inodes) &&
- atomic_read(&next_i->i_count)) {
- spin_lock(&next_i->i_lock);
- if (!(next_i->i_state & (I_FREEING | I_WILL_FREE))) {
- __iget(next_i);
- need_iput = next_i;
- }
- spin_unlock(&next_i->i_lock);
- }
+ __iget(inode);
+ spin_unlock(&inode->i_lock);
+ spin_unlock(lock);
- /*
- * We can safely drop s_inode_list_lock here because we hold
- * references on both inode and next_i. Also no new inodes
- * will be added since the umount has begun.
- */
- spin_unlock(&sb->s_inode_list_lock);
+ iput(*toput_inode);
+ *toput_inode = inode;
- if (need_iput_tmp)
- iput(need_iput_tmp);
+ /* for each watch, send FS_UNMOUNT and then remove it */
+ fsnotify(inode, FS_UNMOUNT, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
+ fsnotify_inode_delete(inode);
- /* for each watch, send FS_UNMOUNT and then remove it */
- fsnotify(inode, FS_UNMOUNT, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
+ /*
+ * Even though we have dropped the lock here, we can return LRU_SKIP as
+ * we have a reference to the current inode and so it's next pointer is
+ * guaranteed to be valid even though we dropped the list lock.
+ */
+ spin_lock(lock);
+ return LRU_SKIP;
+}
- fsnotify_inode_delete(inode);
+/**
+ * fsnotify_unmount_inodes - an sb is unmounting. handle any watched inodes.
+ * @sb: superblock being unmounted.
+ *
+ * Called during unmount with the sb->s_umount held exclusively and so the inode
+ * list will not grow and so a single pass will catch all inodes.
+ */
+void fsnotify_unmount_inodes(struct super_block *sb)
+{
+ struct inode *toput_inode = NULL;
- iput(inode);
+ list_lru_walk(&sb->s_inode_list, fsnotify_unmount_inode, &toput_inode,
+ ULONG_MAX);
- spin_lock(&sb->s_inode_list_lock);
- }
- spin_unlock(&sb->s_inode_list_lock);
+ /* the list walk doesn't release the last inode it sees! */
+ iput(toput_inode);
}
diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
index fe93be2..829d7c8 100644
--- a/fs/quota/dquot.c
+++ b/fs/quota/dquot.c
@@ -901,55 +901,79 @@ static int dqinit_needed(struct inode *inode, int type)
return 0;
}
-/* This routine is guarded by dqonoff_mutex mutex */
-static void add_dquot_ref(struct super_block *sb, int type)
+static enum lru_status
+add_dquot_ref_type(struct list_head *item, spinlock_t *lock, void *cb_arg,
+ int type)
{
- struct inode *inode, *old_inode = NULL;
-#ifdef CONFIG_QUOTA_DEBUG
- int reserved = 0;
-#endif
+ struct inode **toput_inode = cb_arg;
+ struct inode *inode = container_of(item, struct inode, i_sb_list);
- 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)) ||
- !atomic_read(&inode->i_writecount) ||
- !dqinit_needed(inode, type)) {
- spin_unlock(&inode->i_lock);
- continue;
- }
- __iget(inode);
+ spin_lock(&inode->i_lock);
+ if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) ||
+ !atomic_read(&inode->i_writecount) ||
+ !dqinit_needed(inode, type)) {
spin_unlock(&inode->i_lock);
- spin_unlock(&sb->s_inode_list_lock);
-
-#ifdef CONFIG_QUOTA_DEBUG
- if (unlikely(inode_get_rsv_space(inode) > 0))
- reserved = 1;
-#endif
- iput(old_inode);
- __dquot_initialize(inode, type);
-
- /*
- * We hold a reference to 'inode' so it couldn't have been
- * removed from s_inodes list while we dropped the
- * s_inode_list_lock. We cannot iput the inode now as we can be
- * holding the last reference and we cannot iput it under
- * s_inode_list_lock. So we keep the reference and iput it
- * later.
- */
- old_inode = inode;
- spin_lock(&sb->s_inode_list_lock);
+ return LRU_SKIP;
}
- spin_unlock(&sb->s_inode_list_lock);
- iput(old_inode);
+
+ __iget(inode);
+ spin_unlock(&inode->i_lock);
+ spin_unlock(lock);
#ifdef CONFIG_QUOTA_DEBUG
- if (reserved) {
+ if (unlikely(inode_get_rsv_space(inode) > 0))
quota_error(sb, "Writes happened before quota was turned on "
"thus quota information is probably inconsistent. "
"Please run quotacheck(8)");
- }
#endif
+
+ iput(*toput_inode);
+ *toput_inode = inode;
+
+ __dquot_initialize(inode, type);
+
+ /*
+ * Even though we have dropped the lock here, we can return LRU_SKIP as
+ * we have a reference to the current inode and so it's next pointer is
+ * guaranteed to be valid even though we dropped the list lock.
+ */
+ spin_lock(lock);
+ return LRU_SKIP;
+}
+
+static enum lru_status
+add_dquot_ref_usr(struct list_head *item, spinlock_t *lock, void *cb_arg)
+{
+ return add_dquot_ref_type(item, lock, cb_arg, USRQUOTA);
+}
+
+static enum lru_status
+add_dquot_ref_grp(struct list_head *item, spinlock_t *lock, void *cb_arg)
+{
+ return add_dquot_ref_type(item, lock, cb_arg, GRPQUOTA);
+}
+
+/* add_dquot_ref is protected by the dqonoff_mutex mutex */
+void add_dquot_ref(struct super_block *sb, int type)
+{
+ struct inode *toput_inode = NULL;
+ list_lru_walk_cb isolate;
+
+ switch (type) {
+ case USRQUOTA:
+ isolate = add_dquot_ref_usr;
+ break;
+ case GRPQUOTA:
+ isolate = add_dquot_ref_grp;
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ return;
+ }
+ list_lru_walk(&sb->s_inode_list, isolate, &toput_inode, ULONG_MAX);
+
+ /* the list walk doesn't release the last inode it sees! */
+ iput(toput_inode);
}
/*
@@ -1015,34 +1039,62 @@ static void put_dquot_list(struct list_head *tofree_head)
}
}
-static void remove_dquot_ref(struct super_block *sb, int type,
- struct list_head *tofree_head)
+static enum lru_status
+remove_dquot_ref_type(struct list_head *item, spinlock_t *lock, void *cb_arg,
+ int type)
{
- struct inode *inode;
- int reserved = 0;
+ struct list_head *tofree_head = cb_arg;
+ struct inode *inode = container_of(item, struct inode, i_sb_list);
- 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
- * have quota pointer initialized. Luckily, we need to touch
- * only quota pointers and these have separate locking
- * (dqptr_sem).
- */
- if (!IS_NOQUOTA(inode)) {
- if (unlikely(inode_get_rsv_space(inode) > 0))
- reserved = 1;
- remove_inode_dquot_ref(inode, type, tofree_head);
- }
- }
- spin_unlock(&sb->s_inode_list_lock);
+ /*
+ * We have to scan also I_NEW inodes because they can already
+ * have quota pointer initialized. Luckily, we need to touch
+ * only quota pointers and these have separate locking
+ * (dqptr_sem).
+ */
+ if (!IS_NOQUOTA(inode)) {
#ifdef CONFIG_QUOTA_DEBUG
- if (reserved) {
- printk(KERN_WARNING "VFS (%s): Writes happened after quota"
+ if (unlikely(inode_get_rsv_space(inode) > 0)) {
+ printk_ratelimited(KERN_WARNING
+ "VFS (%s): Writes happened after quota"
" was disabled thus quota information is probably "
"inconsistent. Please run quotacheck(8).\n", sb->s_id);
- }
+ }
#endif
+ remove_inode_dquot_ref(inode, type, tofree_head);
+ }
+ return LRU_SKIP;
+}
+
+static enum lru_status
+remove_dquot_ref_usr(struct list_head *item, spinlock_t *lock, void *cb_arg)
+{
+ return remove_dquot_ref_type(item, lock, cb_arg, USRQUOTA);
+}
+
+static enum lru_status
+remove_dquot_ref_grp(struct list_head *item, spinlock_t *lock, void *cb_arg)
+{
+ return remove_dquot_ref_type(item, lock, cb_arg, GRPQUOTA);
+}
+
+static void remove_dquot_ref(struct super_block *sb, int type,
+ struct list_head *tofree_head)
+{
+ list_lru_walk_cb isolate;
+
+ switch (type) {
+ case USRQUOTA:
+ isolate = remove_dquot_ref_usr;
+ break;
+ case GRPQUOTA:
+ isolate = remove_dquot_ref_grp;
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ return;
+ }
+ list_lru_walk(&sb->s_inode_list, isolate, tofree_head, ULONG_MAX);
}
/* Gather all references from inodes and drop them */
diff --git a/fs/super.c b/fs/super.c
index 7f98fd6..97e2274 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -201,13 +201,13 @@ 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);
mutex_init(&s->s_sync_lock);
- INIT_LIST_HEAD(&s->s_inodes);
- spin_lock_init(&s->s_inode_list_lock);
if (list_lru_init(&s->s_dentry_lru))
goto err_out;
if (list_lru_init(&s->s_inode_lru))
goto err_out_dentry_lru;
+ if (list_lru_init(&s->s_inode_list))
+ goto err_out_inode_lru;
INIT_LIST_HEAD(&s->s_mounts);
init_rwsem(&s->s_umount);
@@ -249,6 +249,8 @@ static struct super_block *alloc_super(struct file_system_type *type, int flags)
out:
return s;
+err_out_inode_lru:
+ list_lru_destroy(&s->s_inode_lru);
err_out_dentry_lru:
list_lru_destroy(&s->s_dentry_lru);
err_out:
@@ -332,6 +334,7 @@ void deactivate_locked_super(struct super_block *s)
unregister_shrinker(&s->s_shrink);
list_lru_destroy(&s->s_dentry_lru);
list_lru_destroy(&s->s_inode_lru);
+ list_lru_destroy(&s->s_inode_list);
put_filesystem(fs);
put_super(s);
@@ -450,7 +453,7 @@ void generic_shutdown_super(struct super_block *sb)
if (sop->put_super)
sop->put_super(sb);
- if (!list_empty(&sb->s_inodes)) {
+ if (list_lru_count(&sb->s_inode_list)) {
printk("VFS: Busy inodes after unmount of %s. "
"Self-destruct in 5 seconds. Have a nice day...\n",
sb->s_id);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 5bb84b1..28baf4d 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1331,9 +1331,12 @@ struct super_block {
struct list_lru s_dentry_lru ____cacheline_aligned_in_smp;
struct list_lru s_inode_lru ____cacheline_aligned_in_smp;
- /* s_inode_list_lock protects s_inodes */
- spinlock_t s_inode_list_lock ____cacheline_aligned_in_smp;
- struct list_head s_inodes; /* all inodes */
+ /*
+ * the inode list is not strictly used as a LRU, but uses the list_lru
+ * construct to provide a scalable list implemenation for adding,
+ * removing and walking the inodes cached in memory.
+ */
+ struct list_lru s_inode_list ____cacheline_aligned_in_smp;
};
extern struct timespec current_fs_time(struct super_block *sb);
--
1.8.3.2
--
To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
