*
* inode->i_lock protects:
* inode->i_state, inode->i_hash, __iget()
- * inode_lru_lock protects:
+ * inode->i_sb->s_inode_lru_lock protects:
* inode->i_sb->s_inode_lru, inode->i_lru
* inode_sb_list_lock protects:
* sb->s_inodes, inode->i_sb_list
- * inode_wb_list_lock protects:
+ * bdi->wb.list_lock protects:
* bdi->wb.b_{dirty,io,more_io}, inode->i_wb_list
* inode_hash_lock protects:
* inode_hashtable, inode->i_hash
*
* inode_sb_list_lock
* inode->i_lock
- * inode_lru_lock
+ * inode->i_sb->s_inode_lru_lock
*
- * inode_wb_list_lock
+ * bdi->wb.list_lock
* inode->i_lock
*
* inode_hash_lock
static struct hlist_head *inode_hashtable __read_mostly;
static __cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_hash_lock);
-static DEFINE_SPINLOCK(inode_lru_lock);
-
__cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_sb_list_lock);
-__cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_wb_list_lock);
-
-/*
- * iprune_sem provides exclusion between the icache shrinking and the
- * umount path.
- *
- * We don't actually need it to protect anything in the umount path,
- * but only need to cycle through it to make sure any inode that
- * prune_icache took off the LRU list has been fully torn down by the
- * time we are past evict_inodes.
- */
-static DECLARE_RWSEM(iprune_sem);
/*
* Empty aops. Can be used for the cases where the user does not
mutex_init(&inode->i_mutex);
lockdep_set_class(&inode->i_mutex, &sb->s_type->i_mutex_key);
- init_rwsem(&inode->i_alloc_sem);
- lockdep_set_class(&inode->i_alloc_sem, &sb->s_type->i_alloc_sem_key);
+ atomic_set(&inode->i_dio_count, 0);
mapping->a_ops = &empty_aops;
mapping->host = inode;
static void inode_lru_list_add(struct inode *inode)
{
- spin_lock(&inode_lru_lock);
+ spin_lock(&inode->i_sb->s_inode_lru_lock);
if (list_empty(&inode->i_lru)) {
list_add(&inode->i_lru, &inode->i_sb->s_inode_lru);
inode->i_sb->s_nr_inodes_unused++;
this_cpu_inc(nr_unused);
}
- spin_unlock(&inode_lru_lock);
+ spin_unlock(&inode->i_sb->s_inode_lru_lock);
}
static void inode_lru_list_del(struct inode *inode)
{
- spin_lock(&inode_lru_lock);
+ spin_lock(&inode->i_sb->s_inode_lru_lock);
if (!list_empty(&inode->i_lru)) {
list_del_init(&inode->i_lru);
inode->i_sb->s_nr_inodes_unused--;
this_cpu_dec(nr_unused);
}
- spin_unlock(&inode_lru_lock);
+ spin_unlock(&inode->i_sb->s_inode_lru_lock);
}
/**
spin_unlock(&inode_sb_list_lock);
dispose_list(&dispose);
-
- /*
- * Cycle through iprune_sem to make sure any inode that prune_icache
- * moved off the list before we took the lock has been fully torn
- * down.
- */
- down_write(&iprune_sem);
- up_write(&iprune_sem);
}
/**
}
/*
- * Scan `goal' inodes on the unused list for freeable ones. They are moved to a
- * temporary list and then are freed outside inode_lru_lock by dispose_list().
+ * Walk the superblock inode LRU for freeable inodes and attempt to free them.
+ * This is called from the superblock shrinker function with a number of inodes
+ * to trim from the LRU. Inodes to be freed are moved to a temporary list and
+ * then are freed outside inode_lock by dispose_list().
*
* Any inodes which are pinned purely because of attached pagecache have their
* pagecache removed. If the inode has metadata buffers attached to
* LRU does not have strict ordering. Hence we don't want to reclaim inodes
* with this flag set because they are the inodes that are out of order.
*/
-static void shrink_icache_sb(struct super_block *sb, int *nr_to_scan)
+void prune_icache_sb(struct super_block *sb, int nr_to_scan)
{
LIST_HEAD(freeable);
int nr_scanned;
unsigned long reap = 0;
- spin_lock(&inode_lru_lock);
- for (nr_scanned = *nr_to_scan; nr_scanned >= 0; nr_scanned--) {
+ spin_lock(&sb->s_inode_lru_lock);
+ for (nr_scanned = nr_to_scan; nr_scanned >= 0; nr_scanned--) {
struct inode *inode;
if (list_empty(&sb->s_inode_lru))
inode = list_entry(sb->s_inode_lru.prev, struct inode, i_lru);
/*
- * we are inverting the inode_lru_lock/inode->i_lock here,
+ * we are inverting the sb->s_inode_lru_lock/inode->i_lock here,
* so use a trylock. If we fail to get the lock, just move the
* inode to the back of the list so we don't spin on it.
*/
if (inode_has_buffers(inode) || inode->i_data.nrpages) {
__iget(inode);
spin_unlock(&inode->i_lock);
- spin_unlock(&inode_lru_lock);
+ spin_unlock(&sb->s_inode_lru_lock);
if (remove_inode_buffers(inode))
reap += invalidate_mapping_pages(&inode->i_data,
0, -1);
iput(inode);
- spin_lock(&inode_lru_lock);
+ spin_lock(&sb->s_inode_lru_lock);
if (inode != list_entry(sb->s_inode_lru.next,
struct inode, i_lru))
__count_vm_events(KSWAPD_INODESTEAL, reap);
else
__count_vm_events(PGINODESTEAL, reap);
- spin_unlock(&inode_lru_lock);
- *nr_to_scan = nr_scanned;
+ spin_unlock(&sb->s_inode_lru_lock);
dispose_list(&freeable);
}
-static void prune_icache(int count)
-{
- struct super_block *sb, *p = NULL;
- int w_count;
- int unused = inodes_stat.nr_unused;
- int prune_ratio;
- int pruned;
-
- if (unused == 0 || count == 0)
- return;
- down_read(&iprune_sem);
- if (count >= unused)
- prune_ratio = 1;
- else
- prune_ratio = unused / count;
- spin_lock(&sb_lock);
- list_for_each_entry(sb, &super_blocks, s_list) {
- if (list_empty(&sb->s_instances))
- continue;
- if (sb->s_nr_inodes_unused == 0)
- continue;
- sb->s_count++;
- /* Now, we reclaim unused dentrins with fairness.
- * We reclaim them same percentage from each superblock.
- * We calculate number of dentries to scan on this sb
- * as follows, but the implementation is arranged to avoid
- * overflows:
- * number of dentries to scan on this sb =
- * count * (number of dentries on this sb /
- * number of dentries in the machine)
- */
- spin_unlock(&sb_lock);
- if (prune_ratio != 1)
- w_count = (sb->s_nr_inodes_unused / prune_ratio) + 1;
- else
- w_count = sb->s_nr_inodes_unused;
- pruned = w_count;
- /*
- * We need to be sure this filesystem isn't being unmounted,
- * otherwise we could race with generic_shutdown_super(), and
- * end up holding a reference to an inode while the filesystem
- * is unmounted. So we try to get s_umount, and make sure
- * s_root isn't NULL.
- */
- if (down_read_trylock(&sb->s_umount)) {
- if ((sb->s_root != NULL) &&
- (!list_empty(&sb->s_dentry_lru))) {
- shrink_icache_sb(sb, &w_count);
- pruned -= w_count;
- }
- up_read(&sb->s_umount);
- }
- spin_lock(&sb_lock);
- if (p)
- __put_super(p);
- count -= pruned;
- p = sb;
- /* more work left to do? */
- if (count <= 0)
- break;
- }
- if (p)
- __put_super(p);
- spin_unlock(&sb_lock);
- up_read(&iprune_sem);
-}
-
-/*
- * shrink_icache_memory() will attempt to reclaim some unused inodes. Here,
- * "unused" means that no dentries are referring to the inodes: the files are
- * not open and the dcache references to those inodes have already been
- * reclaimed.
- *
- * This function is passed the number of inodes to scan, and it returns the
- * total number of remaining possibly-reclaimable inodes.
- */
-static int shrink_icache_memory(struct shrinker *shrink,
- struct shrink_control *sc)
-{
- int nr = sc->nr_to_scan;
- gfp_t gfp_mask = sc->gfp_mask;
-
- if (nr) {
- /*
- * Nasty deadlock avoidance. We may hold various FS locks,
- * and we don't want to recurse into the FS that called us
- * in clear_inode() and friends..
- */
- if (!(gfp_mask & __GFP_FS))
- return -1;
- prune_icache(nr);
- }
- return (get_nr_inodes_unused() / 100) * sysctl_vfs_cache_pressure;
-}
-
-static struct shrinker icache_shrinker = {
- .shrink = shrink_icache_memory,
- .seeks = DEFAULT_SEEKS,
-};
-
static void __wait_on_freeing_inode(struct inode *inode);
/*
* Called with the inode lock held.
(SLAB_RECLAIM_ACCOUNT|SLAB_PANIC|
SLAB_MEM_SPREAD),
init_once);
- register_shrinker(&icache_shrinker);
/* Hash may have been set up in inode_init_early */
if (!hashdist)
git.openpandora.org / pandora-kernel.git / blobdiff