Btrfs: allocator optimizations, truncate readahead
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 1497ff9..e3c6bfe 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -12,6 +12,33 @@
static int del_pending_extents(struct btrfs_trans_handle *trans, struct
btrfs_root *extent_root);
+static void reada_extent_leaves(struct btrfs_root *root,
+ struct btrfs_path *path, u64 limit)
+{
+ struct btrfs_node *node;
+ int i;
+ int nritems;
+ u64 item_objectid;
+ u64 blocknr;
+ int slot;
+ int ret;
+
+ if (!path->nodes[1])
+ return;
+ node = btrfs_buffer_node(path->nodes[1]);
+ slot = path->slots[1] + 1;
+ nritems = btrfs_header_nritems(&node->header);
+ for (i = slot; i < nritems && i < slot + 8; i++) {
+ item_objectid = btrfs_disk_key_objectid(&node->ptrs[i].key);
+ if (item_objectid > limit)
+ break;
+ blocknr = btrfs_node_blockptr(node, i);
+ ret = readahead_tree_block(root, blocknr);
+ if (ret)
+ break;
+ }
+}
+
static int cache_block_group(struct btrfs_root *root,
struct btrfs_block_group_cache *block_group)
{
@@ -24,6 +51,7 @@
u64 i;
u64 last = 0;
u64 hole_size;
+ u64 limit;
int found = 0;
root = root->fs_info->extent_root;
@@ -46,14 +74,17 @@
return ret;
if (ret && path->slots[0] > 0)
path->slots[0]--;
+ limit = block_group->key.objectid + block_group->key.offset;
+ reada_extent_leaves(root, path, limit);
while(1) {
leaf = btrfs_buffer_leaf(path->nodes[0]);
slot = path->slots[0];
if (slot >= btrfs_header_nritems(&leaf->header)) {
+ reada_extent_leaves(root, path, limit);
ret = btrfs_next_leaf(root, path);
- if (ret == 0)
+ if (ret == 0) {
continue;
- else {
+ } else {
if (found) {
hole_size = block_group->key.objectid +
block_group->key.offset - last;
@@ -187,7 +218,7 @@
return max((*cache_ret)->last_alloc, search_start);
}
cache = btrfs_find_block_group(root, cache,
- last + cache->key.offset - 1, 0);
+ last + cache->key.offset - 1, 0, 0);
*cache_ret = cache;
goto again;
}
@@ -195,7 +226,7 @@
struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root,
struct btrfs_block_group_cache
*hint, u64 search_start,
- int data)
+ int data, int owner)
{
struct btrfs_block_group_cache *cache[8];
struct btrfs_block_group_cache *found_group = NULL;
@@ -207,6 +238,10 @@
int i;
int ret;
int full_search = 0;
+ int factor = 8;
+
+ if (!owner)
+ factor = 5;
if (data)
radix = &info->block_group_data_radix;
@@ -219,14 +254,14 @@
if (shint->data == data) {
used = btrfs_block_group_used(&shint->item);
if (used + shint->pinned <
- (shint->key.offset * 8) / 10) {
+ (shint->key.offset * factor) / 10) {
return shint;
}
}
}
if (hint && hint->data == data) {
used = btrfs_block_group_used(&hint->item);
- if (used + hint->pinned < (hint->key.offset * 8) / 10) {
+ if (used + hint->pinned < (hint->key.offset * factor) / 10) {
return hint;
}
if (used >= (hint->key.offset * 8) / 10) {
@@ -261,7 +296,7 @@
cache[i]->key.offset;
used = btrfs_block_group_used(&cache[i]->item);
if (used + cache[i]->pinned <
- (cache[i]->key.offset * 8) / 10) {
+ (cache[i]->key.offset * factor) / 10) {
found_group = cache[i];
goto found;
}
@@ -272,6 +307,7 @@
BTRFS_BLOCK_GROUP_AVAIL);
}
}
+ cond_resched();
}
last = hint_last;
again:
@@ -295,13 +331,16 @@
BTRFS_BLOCK_GROUP_AVAIL);
}
}
+ cond_resched();
}
if (!full_search) {
+printk("find block group doing full search data %d start %Lu\n", data, search_start);
last = search_start;
full_search = 1;
goto again;
}
if (!found_group) {
+printk("find block group bailing to zero data %d\n", data);
ret = radix_tree_gang_lookup(radix,
(void **)&found_group, 0, 1);
BUG_ON(ret != 1);
@@ -554,8 +593,8 @@
blocknr + i);
}
}
- if (old_val < (cache->key.offset * 6) / 10 &&
- old_val + num >= (cache->key.offset * 6) / 10) {
+ if (old_val < (cache->key.offset * 5) / 10 &&
+ old_val + num >= (cache->key.offset * 5) / 10) {
printk("group %Lu now available\n", cache->key.objectid);
radix_tree_tag_set(cache->radix,
cache->key.objectid +
@@ -842,6 +881,7 @@
int level;
struct btrfs_block_group_cache *block_group;
int full_scan = 0;
+ u64 limit;
path = btrfs_alloc_path();
ins->flags = 0;
@@ -858,11 +898,11 @@
if (search_start) {
block_group = lookup_block_group(info, search_start);
block_group = btrfs_find_block_group(root, block_group,
- search_start, data);
+ search_start, data, 1);
} else {
block_group = btrfs_find_block_group(root,
trans->block_group, 0,
- data);
+ data, 1);
}
check_failed:
@@ -916,6 +956,12 @@
info->extent_tree_prealloc_nr = 0;
total_found = 0;
}
+ if (start_found)
+ limit = last_block +
+ block_group->key.offset / 2;
+ else
+ limit = search_start +
+ block_group->key.offset / 2;
ret = btrfs_next_leaf(root, path);
if (ret == 0)
continue;
@@ -960,6 +1006,7 @@
}
next:
path->slots[0]++;
+ cond_resched();
}
// FIXME -ENOSPC
check_pending:
@@ -1049,7 +1096,8 @@
block_group = lookup_block_group(info, search_start);
if (!full_scan)
block_group = btrfs_find_block_group(root, block_group,
- search_start, data);
+ search_start, data, 0);
+ cond_resched();
goto check_failed;
error:
@@ -1102,7 +1150,7 @@
* in the correct block group.
*/
if (data) {
- ret = find_free_extent(trans, root, 0, search_start,
+ ret = find_free_extent(trans, root, 0, 0,
search_end, &prealloc_key, 0);
if (ret) {
return ret;
@@ -1173,7 +1221,7 @@
struct buffer_head *buf;
ret = btrfs_alloc_extent(trans, root, root->root_key.objectid,
- 1, 0, (unsigned long)-1, &ins, 0);
+ 1, hint, (unsigned long)-1, &ins, 0);
if (ret) {
BUG();
return NULL;