[PATCH 1/6] f2fs: speed up shrinking extent_node cache
From: Jaegeuk Kim
Date: Mon Jan 25 2016 - 17:05:48 EST
This patch speeds up extent_node shrinker by introducing linked list.
Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
---
fs/f2fs/extent_cache.c | 74 ++++++++++++++++++++++----------------------------
fs/f2fs/f2fs.h | 2 ++
2 files changed, 35 insertions(+), 41 deletions(-)
diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
index ccd5c63..18311ff 100644
--- a/fs/f2fs/extent_cache.c
+++ b/fs/f2fs/extent_cache.c
@@ -32,7 +32,9 @@ static struct extent_node *__attach_extent_node(struct f2fs_sb_info *sbi,
return NULL;
en->ei = *ei;
+ en->et = et;
INIT_LIST_HEAD(&en->list);
+ INIT_LIST_HEAD(&en->vlist);
rb_link_node(&en->rb_node, parent, p);
rb_insert_color(&en->rb_node, &et->root);
@@ -129,7 +131,7 @@ static struct extent_node *__init_extent_tree(struct f2fs_sb_info *sbi,
}
static unsigned int __free_extent_tree(struct f2fs_sb_info *sbi,
- struct extent_tree *et, bool free_all)
+ struct extent_tree *et)
{
struct rb_node *node, *next;
struct extent_node *en;
@@ -137,17 +139,19 @@ static unsigned int __free_extent_tree(struct f2fs_sb_info *sbi,
node = rb_first(&et->root);
while (node) {
+ bool need_free = false;
+
next = rb_next(node);
en = rb_entry(node, struct extent_node, rb_node);
- if (free_all) {
- spin_lock(&sbi->extent_lock);
- if (!list_empty(&en->list))
- list_del_init(&en->list);
- spin_unlock(&sbi->extent_lock);
+ spin_lock(&sbi->extent_lock);
+ if (!list_empty(&en->list)) {
+ list_del_init(&en->list);
+ need_free = true;
}
+ spin_unlock(&sbi->extent_lock);
- if (free_all || list_empty(&en->list)) {
+ if (need_free) {
__detach_extent_node(sbi, et, en);
kmem_cache_free(extent_node_slab, en);
}
@@ -438,6 +442,7 @@ static unsigned int f2fs_update_extent_tree_range(struct inode *inode,
while (en && en->ei.fofs < end) {
unsigned int org_end;
int parts = 0; /* # of parts current extent split into */
+ bool need_free = false;
next_en = en1 = NULL;
@@ -493,14 +498,16 @@ static unsigned int f2fs_update_extent_tree_range(struct inode *inode,
/* update in global extent list */
spin_lock(&sbi->extent_lock);
- if (!parts && !list_empty(&en->list))
+ if (!parts && !list_empty(&en->list)) {
list_del(&en->list);
+ need_free = true;
+ }
if (en1)
list_add_tail(&en1->list, &sbi->extent_list);
spin_unlock(&sbi->extent_lock);
/* release extent node */
- if (!parts)
+ if (!parts && need_free)
kmem_cache_free(extent_node_slab, en);
en = next_en;
@@ -509,6 +516,7 @@ static unsigned int f2fs_update_extent_tree_range(struct inode *inode,
/* 3. update extent in extent cache */
if (blkaddr) {
struct extent_node *den = NULL;
+ bool need_free = false;
set_extent_info(&ei, fofs, blkaddr, len);
en1 = __try_merge_extent_node(sbi, et, &ei, &den,
@@ -532,16 +540,18 @@ static unsigned int f2fs_update_extent_tree_range(struct inode *inode,
else
list_move_tail(&en1->list, &sbi->extent_list);
}
- if (den && !list_empty(&den->list))
+ if (den && !list_empty(&den->list)) {
list_del(&den->list);
+ need_free = true;
+ }
spin_unlock(&sbi->extent_lock);
- if (den)
+ if (den && need_free)
kmem_cache_free(extent_node_slab, den);
}
if (is_inode_flag_set(F2FS_I(inode), FI_NO_EXTENT))
- __free_extent_tree(sbi, et, true);
+ __free_extent_tree(sbi, et);
write_unlock(&et->lock);
@@ -550,14 +560,12 @@ static unsigned int f2fs_update_extent_tree_range(struct inode *inode,
unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
{
- struct extent_tree *treevec[EXT_TREE_VEC_SIZE];
struct extent_tree *et, *next;
struct extent_node *en, *tmp;
- unsigned long ino = F2FS_ROOT_INO(sbi);
- unsigned int found;
unsigned int node_cnt = 0, tree_cnt = 0;
int remained;
bool do_free = false;
+ LIST_HEAD(victim_list);
if (!test_opt(sbi, EXTENT_CACHE))
return 0;
@@ -572,7 +580,7 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
list_for_each_entry_safe(et, next, &sbi->zombie_list, list) {
if (atomic_read(&et->node_cnt)) {
write_lock(&et->lock);
- node_cnt += __free_extent_tree(sbi, et, true);
+ node_cnt += __free_extent_tree(sbi, et);
write_unlock(&et->lock);
}
@@ -600,6 +608,8 @@ free_node:
if (!remained--)
break;
list_del_init(&en->list);
+ list_add_tail(&en->vlist, &victim_list);
+ tree_cnt++;
do_free = true;
}
spin_unlock(&sbi->extent_lock);
@@ -607,31 +617,13 @@ free_node:
if (do_free == false)
goto unlock_out;
- /*
- * reset ino for searching victims from beginning of global extent tree.
- */
- ino = F2FS_ROOT_INO(sbi);
-
- while ((found = radix_tree_gang_lookup(&sbi->extent_tree_root,
- (void **)treevec, ino, EXT_TREE_VEC_SIZE))) {
- unsigned i;
-
- ino = treevec[found - 1]->ino + 1;
- for (i = 0; i < found; i++) {
- struct extent_tree *et = treevec[i];
-
- if (!atomic_read(&et->node_cnt))
- continue;
-
- if (write_trylock(&et->lock)) {
- node_cnt += __free_extent_tree(sbi, et, false);
- write_unlock(&et->lock);
- }
-
- if (node_cnt + tree_cnt >= nr_shrink)
- goto unlock_out;
- }
+ list_for_each_entry_safe(en, tmp, &victim_list, vlist) {
+ write_lock(&en->et->lock);
+ __detach_extent_node(sbi, en->et, en);
+ write_unlock(&en->et->lock);
+ kmem_cache_free(extent_node_slab, en);
}
+
unlock_out:
up_write(&sbi->extent_tree_lock);
out:
@@ -650,7 +642,7 @@ unsigned int f2fs_destroy_extent_node(struct inode *inode)
return 0;
write_lock(&et->lock);
- node_cnt = __free_extent_tree(sbi, et, true);
+ node_cnt = __free_extent_tree(sbi, et);
write_unlock(&et->lock);
return node_cnt;
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index c4e723b..0bbbfed 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -353,7 +353,9 @@ struct extent_info {
struct extent_node {
struct rb_node rb_node; /* rb node located in rb-tree */
struct list_head list; /* node in global extent list of sbi */
+ struct list_head vlist; /* node in victim extent list */
struct extent_info ei; /* extent info */
+ struct extent_tree *et; /* extent tree pointer */
};
struct extent_tree {
--
2.6.3