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 __ext4_es_shrink(struct ext4_sb_info *sbi, int nr_to_scan,
- struct ext4_inode_info *locked_ei);
+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);
int __init ext4_init_es(void)
{
trace_ext4_es_find_delayed_extent_range_exit(inode, es);
}
+static void ext4_es_list_add(struct inode *inode)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+
+ if (!list_empty(&ei->i_es_list))
+ return;
+
+ spin_lock(&sbi->s_es_lock);
+ if (list_empty(&ei->i_es_list)) {
+ list_add_tail(&ei->i_es_list, &sbi->s_es_list);
+ sbi->s_es_nr_inode++;
+ }
+ spin_unlock(&sbi->s_es_lock);
+}
+
+static void ext4_es_list_del(struct inode *inode)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+
+ spin_lock(&sbi->s_es_lock);
+ if (!list_empty(&ei->i_es_list)) {
+ list_del_init(&ei->i_es_list);
+ sbi->s_es_nr_inode--;
+ WARN_ON_ONCE(sbi->s_es_nr_inode < 0);
+ }
+ spin_unlock(&sbi->s_es_lock);
+}
+
static struct extent_status *
ext4_es_alloc_extent(struct inode *inode, ext4_lblk_t lblk, ext4_lblk_t len,
ext4_fsblk_t pblk)
* We don't count delayed extent because we never try to reclaim them
*/
if (!ext4_es_is_delayed(es)) {
- EXT4_I(inode)->i_es_lru_nr++;
+ if (!EXT4_I(inode)->i_es_shk_nr++)
+ ext4_es_list_add(inode);
percpu_counter_inc(&EXT4_SB(inode->i_sb)->
- s_es_stats.es_stats_lru_cnt);
+ s_es_stats.es_stats_shk_cnt);
}
EXT4_I(inode)->i_es_all_nr++;
EXT4_I(inode)->i_es_all_nr--;
percpu_counter_dec(&EXT4_SB(inode->i_sb)->s_es_stats.es_stats_all_cnt);
- /* Decrease the lru counter when this es is not delayed */
+ /* Decrease the shrink counter when this es is not delayed */
if (!ext4_es_is_delayed(es)) {
- BUG_ON(EXT4_I(inode)->i_es_lru_nr == 0);
- EXT4_I(inode)->i_es_lru_nr--;
+ BUG_ON(EXT4_I(inode)->i_es_shk_nr == 0);
+ if (!--EXT4_I(inode)->i_es_shk_nr)
+ ext4_es_list_del(inode);
percpu_counter_dec(&EXT4_SB(inode->i_sb)->
- s_es_stats.es_stats_lru_cnt);
+ s_es_stats.es_stats_shk_cnt);
}
kmem_cache_free(ext4_es_cachep, es);
static int ext4_es_can_be_merged(struct extent_status *es1,
struct extent_status *es2)
{
- if (ext4_es_status(es1) != ext4_es_status(es2))
+ if (ext4_es_type(es1) != ext4_es_type(es2))
return 0;
if (((__u64) es1->es_len) + es2->es_len > EXT_MAX_BLOCKS) {
es1 = rb_entry(node, struct extent_status, rb_node);
if (ext4_es_can_be_merged(es1, es)) {
es1->es_len += es->es_len;
+ if (ext4_es_is_referenced(es))
+ ext4_es_set_referenced(es1);
rb_erase(&es->rb_node, &tree->root);
ext4_es_free_extent(inode, es);
es = es1;
es1 = rb_entry(node, struct extent_status, rb_node);
if (ext4_es_can_be_merged(es, es1)) {
es->es_len += es1->es_len;
+ if (ext4_es_is_referenced(es1))
+ ext4_es_set_referenced(es);
rb_erase(node, &tree->root);
ext4_es_free_extent(inode, es1);
}
goto error;
retry:
err = __es_insert_extent(inode, &newes);
- if (err == -ENOMEM && __ext4_es_shrink(EXT4_SB(inode->i_sb), 1,
- EXT4_I(inode)))
+ if (err == -ENOMEM && __es_shrink(EXT4_SB(inode->i_sb),
+ 128, EXT4_I(inode)))
goto retry;
if (err == -ENOMEM && !ext4_es_is_delayed(&newes))
err = 0;
es->es_lblk = es1->es_lblk;
es->es_len = es1->es_len;
es->es_pblk = es1->es_pblk;
+ if (!ext4_es_is_referenced(es))
+ ext4_es_set_referenced(es);
stats->es_stats_cache_hits++;
} else {
stats->es_stats_cache_misses++;
es->es_lblk = orig_es.es_lblk;
es->es_len = orig_es.es_len;
if ((err == -ENOMEM) &&
- __ext4_es_shrink(EXT4_SB(inode->i_sb), 1,
- EXT4_I(inode)))
+ __es_shrink(EXT4_SB(inode->i_sb),
+ 128, EXT4_I(inode)))
goto retry;
goto out;
}
end = lblk + len - 1;
BUG_ON(end < lblk);
+ /*
+ * ext4_clear_inode() depends on us taking i_es_lock unconditionally
+ * so that we are sure __es_shrink() is done with the inode before it
+ * is reclaimed.
+ */
write_lock(&EXT4_I(inode)->i_es_lock);
err = __es_remove_extent(inode, lblk, end);
write_unlock(&EXT4_I(inode)->i_es_lock);
return err;
}
-static int ext4_inode_touch_time_cmp(void *priv, struct list_head *a,
- struct list_head *b)
-{
- struct ext4_inode_info *eia, *eib;
- eia = list_entry(a, struct ext4_inode_info, i_es_lru);
- eib = list_entry(b, struct ext4_inode_info, i_es_lru);
-
- if (ext4_test_inode_state(&eia->vfs_inode, EXT4_STATE_EXT_PRECACHED) &&
- !ext4_test_inode_state(&eib->vfs_inode, EXT4_STATE_EXT_PRECACHED))
- return 1;
- if (!ext4_test_inode_state(&eia->vfs_inode, EXT4_STATE_EXT_PRECACHED) &&
- ext4_test_inode_state(&eib->vfs_inode, EXT4_STATE_EXT_PRECACHED))
- return -1;
- if (eia->i_touch_when == eib->i_touch_when)
- return 0;
- if (time_after(eia->i_touch_when, eib->i_touch_when))
- return 1;
- else
- return -1;
-}
-
-static int __ext4_es_shrink(struct ext4_sb_info *sbi, int nr_to_scan,
- struct ext4_inode_info *locked_ei)
+static int __es_shrink(struct ext4_sb_info *sbi, int nr_to_scan,
+ struct ext4_inode_info *locked_ei)
{
struct ext4_inode_info *ei;
struct ext4_es_stats *es_stats;
- struct list_head *cur, *tmp;
- LIST_HEAD(skipped);
ktime_t start_time;
u64 scan_time;
+ int nr_to_walk;
int nr_shrunk = 0;
- int retried = 0, skip_precached = 1, nr_skipped = 0;
+ int retried = 0, nr_skipped = 0;
es_stats = &sbi->s_es_stats;
start_time = ktime_get();
- spin_lock(&sbi->s_es_lru_lock);
retry:
- list_for_each_safe(cur, tmp, &sbi->s_es_lru) {
- int shrunk;
-
- /*
- * If we have already reclaimed all extents from extent
- * status tree, just stop the loop immediately.
- */
- if (percpu_counter_read_positive(
- &es_stats->es_stats_lru_cnt) == 0)
- break;
-
- ei = list_entry(cur, struct ext4_inode_info, i_es_lru);
+ spin_lock(&sbi->s_es_lock);
+ nr_to_walk = sbi->s_es_nr_inode;
+ while (nr_to_walk-- > 0) {
+ if (list_empty(&sbi->s_es_list)) {
+ spin_unlock(&sbi->s_es_lock);
+ goto out;
+ }
+ ei = list_first_entry(&sbi->s_es_list, struct ext4_inode_info,
+ i_es_list);
+ /* Move the inode to the tail */
+ list_move_tail(&ei->i_es_list, &sbi->s_es_list);
/*
- * Skip the inode that is newer than the last_sorted
- * time. Normally we try hard to avoid shrinking
- * precached inodes, but we will as a last resort.
+ * Normally we try hard to avoid shrinking precached inodes,
+ * but we will as a last resort.
*/
- if ((es_stats->es_stats_last_sorted < ei->i_touch_when) ||
- (skip_precached && ext4_test_inode_state(&ei->vfs_inode,
- EXT4_STATE_EXT_PRECACHED))) {
+ if (!retried && ext4_test_inode_state(&ei->vfs_inode,
+ EXT4_STATE_EXT_PRECACHED)) {
nr_skipped++;
- list_move_tail(cur, &skipped);
continue;
}
- if (ei->i_es_lru_nr == 0 || ei == locked_ei ||
- !write_trylock(&ei->i_es_lock))
+ if (ei == locked_ei || !write_trylock(&ei->i_es_lock)) {
+ nr_skipped++;
continue;
+ }
+ /*
+ * Now we hold i_es_lock which protects us from inode reclaim
+ * freeing inode under us
+ */
+ spin_unlock(&sbi->s_es_lock);
- shrunk = __es_try_to_reclaim_extents(ei, nr_to_scan);
- if (ei->i_es_lru_nr == 0)
- list_del_init(&ei->i_es_lru);
+ 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)
- break;
+ if (nr_to_scan <= 0)
+ goto out;
+ spin_lock(&sbi->s_es_lock);
}
-
- /* Move the newer inodes into the tail of the LRU list. */
- list_splice_tail(&skipped, &sbi->s_es_lru);
- INIT_LIST_HEAD(&skipped);
+ spin_unlock(&sbi->s_es_lock);
/*
* If we skipped any inodes, and we weren't able to make any
- * forward progress, sort the list and try again.
+ * forward progress, try again to scan precached inodes.
*/
if ((nr_shrunk == 0) && nr_skipped && !retried) {
retried++;
- list_sort(NULL, &sbi->s_es_lru, ext4_inode_touch_time_cmp);
- es_stats->es_stats_last_sorted = jiffies;
- ei = list_first_entry(&sbi->s_es_lru, struct ext4_inode_info,
- i_es_lru);
- /*
- * If there are no non-precached inodes left on the
- * list, start releasing precached extents.
- */
- if (ext4_test_inode_state(&ei->vfs_inode,
- EXT4_STATE_EXT_PRECACHED))
- skip_precached = 0;
goto retry;
}
- spin_unlock(&sbi->s_es_lru_lock);
-
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));
if (likely(es_stats->es_stats_scan_time))
es_stats->es_stats_scan_time = (scan_time +
else
es_stats->es_stats_shrunk = nr_shrunk;
- trace_ext4_es_shrink(sbi->s_sb, nr_shrunk, scan_time, skip_precached,
+ trace_ext4_es_shrink(sbi->s_sb, nr_shrunk, scan_time,
nr_skipped, retried);
return nr_shrunk;
}
struct ext4_sb_info *sbi;
sbi = container_of(shrink, struct ext4_sb_info, s_es_shrinker);
- nr = percpu_counter_read_positive(&sbi->s_es_stats.es_stats_lru_cnt);
+ nr = percpu_counter_read_positive(&sbi->s_es_stats.es_stats_shk_cnt);
trace_ext4_es_shrink_count(sbi->s_sb, sc->nr_to_scan, nr);
return nr;
}
int nr_to_scan = sc->nr_to_scan;
int ret, nr_shrunk;
- ret = percpu_counter_read_positive(&sbi->s_es_stats.es_stats_lru_cnt);
+ ret = percpu_counter_read_positive(&sbi->s_es_stats.es_stats_shk_cnt);
trace_ext4_es_shrink_scan_enter(sbi->s_sb, nr_to_scan, ret);
if (!nr_to_scan)
return ret;
- nr_shrunk = __ext4_es_shrink(sbi, nr_to_scan, NULL);
+ nr_shrunk = __es_shrink(sbi, nr_to_scan, NULL);
trace_ext4_es_shrink_scan_exit(sbi->s_sb, nr_shrunk, ret);
return nr_shrunk;
return 0;
/* here we just find an inode that has the max nr. of objects */
- spin_lock(&sbi->s_es_lru_lock);
- list_for_each_entry(ei, &sbi->s_es_lru, i_es_lru) {
+ spin_lock(&sbi->s_es_lock);
+ list_for_each_entry(ei, &sbi->s_es_list, i_es_list) {
inode_cnt++;
if (max && max->i_es_all_nr < ei->i_es_all_nr)
max = ei;
else if (!max)
max = ei;
}
- spin_unlock(&sbi->s_es_lru_lock);
+ spin_unlock(&sbi->s_es_lock);
seq_printf(seq, "stats:\n %lld objects\n %lld reclaimable objects\n",
percpu_counter_sum_positive(&es_stats->es_stats_all_cnt),
- percpu_counter_sum_positive(&es_stats->es_stats_lru_cnt));
+ percpu_counter_sum_positive(&es_stats->es_stats_shk_cnt));
seq_printf(seq, " %lu/%lu cache hits/misses\n",
es_stats->es_stats_cache_hits,
es_stats->es_stats_cache_misses);
- if (es_stats->es_stats_last_sorted != 0)
- seq_printf(seq, " %u ms last sorted interval\n",
- jiffies_to_msecs(jiffies -
- es_stats->es_stats_last_sorted));
if (inode_cnt)
- seq_printf(seq, " %d inodes on lru list\n", inode_cnt);
+ seq_printf(seq, " %d inodes on list\n", inode_cnt);
seq_printf(seq, "average:\n %llu us scan time\n",
div_u64(es_stats->es_stats_scan_time, 1000));
seq_printf(seq,
"maximum:\n %lu inode (%u objects, %u reclaimable)\n"
" %llu us max scan time\n",
- max->vfs_inode.i_ino, max->i_es_all_nr, max->i_es_lru_nr,
+ max->vfs_inode.i_ino, max->i_es_all_nr, max->i_es_shk_nr,
div_u64(es_stats->es_stats_max_scan_time, 1000));
return 0;
{
int err;
- INIT_LIST_HEAD(&sbi->s_es_lru);
- spin_lock_init(&sbi->s_es_lru_lock);
- sbi->s_es_stats.es_stats_last_sorted = 0;
+ /* Make sure we have enough bits for physical block number */
+ BUILD_BUG_ON(ES_SHIFT < 48);
+ INIT_LIST_HEAD(&sbi->s_es_list);
+ sbi->s_es_nr_inode = 0;
+ spin_lock_init(&sbi->s_es_lock);
sbi->s_es_stats.es_stats_shrunk = 0;
sbi->s_es_stats.es_stats_cache_hits = 0;
sbi->s_es_stats.es_stats_cache_misses = 0;
err = percpu_counter_init(&sbi->s_es_stats.es_stats_all_cnt, 0, GFP_KERNEL);
if (err)
return err;
- err = percpu_counter_init(&sbi->s_es_stats.es_stats_lru_cnt, 0, GFP_KERNEL);
+ err = percpu_counter_init(&sbi->s_es_stats.es_stats_shk_cnt, 0, GFP_KERNEL);
if (err)
goto err1;
return 0;
err2:
- percpu_counter_destroy(&sbi->s_es_stats.es_stats_lru_cnt);
+ percpu_counter_destroy(&sbi->s_es_stats.es_stats_shk_cnt);
err1:
percpu_counter_destroy(&sbi->s_es_stats.es_stats_all_cnt);
return err;
if (sbi->s_proc)
remove_proc_entry("es_shrinker_info", sbi->s_proc);
percpu_counter_destroy(&sbi->s_es_stats.es_stats_all_cnt);
- percpu_counter_destroy(&sbi->s_es_stats.es_stats_lru_cnt);
+ percpu_counter_destroy(&sbi->s_es_stats.es_stats_shk_cnt);
unregister_shrinker(&sbi->s_es_shrinker);
}
-void ext4_es_lru_add(struct inode *inode)
+/*
+ * 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 ext4_inode_info *ei = EXT4_I(inode);
- struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
-
- ei->i_touch_when = jiffies;
-
- if (!list_empty(&ei->i_es_lru))
- return;
+ struct inode *inode = &ei->vfs_inode;
+ struct ext4_es_tree *tree = &ei->i_es_tree;
+ struct extent_status *es;
+ struct rb_node *node;
- spin_lock(&sbi->s_es_lru_lock);
- if (list_empty(&ei->i_es_lru))
- list_add_tail(&ei->i_es_lru, &sbi->s_es_lru);
- spin_unlock(&sbi->s_es_lru_lock);
-}
+ 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;
+ }
-void ext4_es_lru_del(struct inode *inode)
-{
- struct ext4_inode_info *ei = EXT4_I(inode);
- struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ (*nr_to_scan)--;
+ node = rb_next(&es->rb_node);
+ /*
+ * We can't reclaim delayed extent from status tree because
+ * fiemap, bigallic, and seek_data/hole need to use it.
+ */
+ if (ext4_es_is_delayed(es))
+ goto next;
+ if (ext4_es_is_referenced(es)) {
+ ext4_es_clear_referenced(es);
+ goto next;
+ }
- spin_lock(&sbi->s_es_lru_lock);
- if (!list_empty(&ei->i_es_lru))
- list_del_init(&ei->i_es_lru);
- spin_unlock(&sbi->s_es_lru_lock);
+ rb_erase(&es->rb_node, &tree->root);
+ ext4_es_free_extent(inode, es);
+ (*nr_shrunk)++;
+next:
+ if (!node)
+ goto out_wrap;
+ es = rb_entry(node, struct extent_status, rb_node);
+ }
+ ei->i_es_shrink_lblk = es->es_lblk;
+ return 1;
+out_wrap:
+ ei->i_es_shrink_lblk = 0;
+ return 0;
}
-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)
{
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;
+ 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_lru_nr == 0)
+ 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");
- node = rb_first(&tree->root);
- while (node != NULL) {
- es = rb_entry(node, struct extent_status, rb_node);
- node = rb_next(&es->rb_node);
- /*
- * We can't reclaim delayed extent from status tree because
- * fiemap, bigallic, and seek_data/hole need to use it.
- */
- 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;
- }
- }
- tree->cache_es = NULL;
+ 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;
}
projects / cascardo / linux.git / blobdiff