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-rw-r--r--fs/ext4/ext4.h5
-rw-r--r--fs/ext4/extents_status.c91
-rw-r--r--fs/ext4/super.c1
3 files changed, 64 insertions, 33 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index ab6caf5..4186ec8 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -881,6 +881,9 @@ struct ext4_inode_info {
struct list_head i_es_list;
unsigned int i_es_all_nr; /* protected by i_es_lock */
unsigned int i_es_shk_nr; /* protected by i_es_lock */
+ ext4_lblk_t i_es_shrink_lblk; /* Offset where we start searching for
+ extents to shrink. Protected by
+ i_es_lock */
/* ialloc */
ext4_group_t i_last_alloc_group;
@@ -1321,7 +1324,7 @@ struct ext4_sb_info {
/* Reclaim extents from extent status tree */
struct shrinker s_es_shrinker;
- struct list_head s_es_list;
+ struct list_head s_es_list; /* List of inodes with reclaimable extents */
long s_es_nr_inode;
struct ext4_es_stats s_es_stats;
struct mb_cache *s_mb_cache;
diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c
index de2d9d8b..8f2aac4 100644
--- a/fs/ext4/extents_status.c
+++ b/fs/ext4/extents_status.c
@@ -147,8 +147,7 @@ static struct kmem_cache *ext4_es_cachep;
static int __es_insert_extent(struct inode *inode, struct extent_status *newes);
static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
ext4_lblk_t end);
-static int __es_try_to_reclaim_extents(struct ext4_inode_info *ei,
- int nr_to_scan);
+static int es_reclaim_extents(struct ext4_inode_info *ei, int *nr_to_scan);
static int __es_shrink(struct ext4_sb_info *sbi, int nr_to_scan,
struct ext4_inode_info *locked_ei);
@@ -716,7 +715,7 @@ int ext4_es_insert_extent(struct inode *inode, ext4_lblk_t lblk,
retry:
err = __es_insert_extent(inode, &newes);
if (err == -ENOMEM && __es_shrink(EXT4_SB(inode->i_sb),
- 1, EXT4_I(inode)))
+ 128, EXT4_I(inode)))
goto retry;
if (err == -ENOMEM && !ext4_es_is_delayed(&newes))
err = 0;
@@ -874,7 +873,7 @@ retry:
es->es_len = orig_es.es_len;
if ((err == -ENOMEM) &&
__es_shrink(EXT4_SB(inode->i_sb),
- 1, EXT4_I(inode)))
+ 128, EXT4_I(inode)))
goto retry;
goto out;
}
@@ -976,8 +975,6 @@ retry:
spin_lock(&sbi->s_es_lock);
nr_to_walk = sbi->s_es_nr_inode;
while (nr_to_walk-- > 0) {
- int shrunk;
-
if (list_empty(&sbi->s_es_list)) {
spin_unlock(&sbi->s_es_lock);
goto out;
@@ -985,7 +982,7 @@ retry:
ei = list_first_entry(&sbi->s_es_list, struct ext4_inode_info,
i_es_list);
/* Move the inode to the tail */
- list_move(&ei->i_es_list, sbi->s_es_list.prev);
+ list_move_tail(&ei->i_es_list, &sbi->s_es_list);
/*
* Normally we try hard to avoid shrinking precached inodes,
@@ -1007,13 +1004,10 @@ retry:
*/
spin_unlock(&sbi->s_es_lock);
- shrunk = __es_try_to_reclaim_extents(ei, nr_to_scan);
+ nr_shrunk += es_reclaim_extents(ei, &nr_to_scan);
write_unlock(&ei->i_es_lock);
- nr_shrunk += shrunk;
- nr_to_scan -= shrunk;
-
- if (nr_to_scan == 0)
+ if (nr_to_scan <= 0)
goto out;
spin_lock(&sbi->s_es_lock);
}
@@ -1029,7 +1023,7 @@ retry:
}
if (locked_ei && nr_shrunk == 0)
- nr_shrunk = __es_try_to_reclaim_extents(locked_ei, nr_to_scan);
+ nr_shrunk = es_reclaim_extents(locked_ei, &nr_to_scan);
out:
scan_time = ktime_to_ns(ktime_sub(ktime_get(), start_time));
@@ -1224,27 +1218,33 @@ void ext4_es_unregister_shrinker(struct ext4_sb_info *sbi)
unregister_shrinker(&sbi->s_es_shrinker);
}
-static int __es_try_to_reclaim_extents(struct ext4_inode_info *ei,
- int nr_to_scan)
+/*
+ * Shrink extents in given inode from ei->i_es_shrink_lblk till end. Scan at
+ * most *nr_to_scan extents, update *nr_to_scan accordingly.
+ *
+ * Return 0 if we hit end of tree / interval, 1 if we exhausted nr_to_scan.
+ * Increment *nr_shrunk by the number of reclaimed extents. Also update
+ * ei->i_es_shrink_lblk to where we should continue scanning.
+ */
+static int es_do_reclaim_extents(struct ext4_inode_info *ei, ext4_lblk_t end,
+ int *nr_to_scan, int *nr_shrunk)
{
struct inode *inode = &ei->vfs_inode;
struct ext4_es_tree *tree = &ei->i_es_tree;
- struct rb_node *node;
struct extent_status *es;
- unsigned long nr_shrunk = 0;
- static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
- DEFAULT_RATELIMIT_BURST);
-
- if (ei->i_es_shk_nr == 0)
- return 0;
+ struct rb_node *node;
- if (ext4_test_inode_state(inode, EXT4_STATE_EXT_PRECACHED) &&
- __ratelimit(&_rs))
- ext4_warning(inode->i_sb, "forced shrink of precached extents");
+ es = __es_tree_search(&tree->root, ei->i_es_shrink_lblk);
+ if (!es)
+ goto out_wrap;
+ node = &es->rb_node;
+ while (*nr_to_scan > 0) {
+ if (es->es_lblk > end) {
+ ei->i_es_shrink_lblk = end + 1;
+ return 0;
+ }
- node = rb_first(&tree->root);
- while (node != NULL) {
- es = rb_entry(node, struct extent_status, rb_node);
+ (*nr_to_scan)--;
node = rb_next(&es->rb_node);
/*
* We can't reclaim delayed extent from status tree because
@@ -1253,11 +1253,38 @@ static int __es_try_to_reclaim_extents(struct ext4_inode_info *ei,
if (!ext4_es_is_delayed(es)) {
rb_erase(&es->rb_node, &tree->root);
ext4_es_free_extent(inode, es);
- nr_shrunk++;
- if (--nr_to_scan == 0)
- break;
+ (*nr_shrunk)++;
}
+ if (!node)
+ goto out_wrap;
+ es = rb_entry(node, struct extent_status, rb_node);
}
- tree->cache_es = NULL;
+ ei->i_es_shrink_lblk = es->es_lblk;
+ return 1;
+out_wrap:
+ ei->i_es_shrink_lblk = 0;
+ return 0;
+}
+
+static int es_reclaim_extents(struct ext4_inode_info *ei, int *nr_to_scan)
+{
+ struct inode *inode = &ei->vfs_inode;
+ int nr_shrunk = 0;
+ ext4_lblk_t start = ei->i_es_shrink_lblk;
+ static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
+ DEFAULT_RATELIMIT_BURST);
+
+ if (ei->i_es_shk_nr == 0)
+ return 0;
+
+ if (ext4_test_inode_state(inode, EXT4_STATE_EXT_PRECACHED) &&
+ __ratelimit(&_rs))
+ ext4_warning(inode->i_sb, "forced shrink of precached extents");
+
+ if (!es_do_reclaim_extents(ei, EXT_MAX_BLOCKS, nr_to_scan, &nr_shrunk) &&
+ start != 0)
+ es_do_reclaim_extents(ei, start - 1, nr_to_scan, &nr_shrunk);
+
+ ei->i_es_tree.cache_es = NULL;
return nr_shrunk;
}
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index e2a17f8..4831849 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -874,6 +874,7 @@ static struct inode *ext4_alloc_inode(struct super_block *sb)
INIT_LIST_HEAD(&ei->i_es_list);
ei->i_es_all_nr = 0;
ei->i_es_shk_nr = 0;
+ ei->i_es_shrink_lblk = 0;
ei->i_reserved_data_blocks = 0;
ei->i_reserved_meta_blocks = 0;
ei->i_allocated_meta_blocks = 0;
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