Relocate file extents in clusters instead of one by one,
so we can make better use of readahead.
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
---
diff -urp 1/fs/btrfs/relocation.c 2/fs/btrfs/relocation.c
--- 1/fs/btrfs/relocation.c 2009-07-03 08:08:34.160847023 +0800
+++ 2/fs/btrfs/relocation.c 2009-07-07 17:23:16.007836927 +0800
@@ -121,6 +121,15 @@ struct inodevec {
int nr;
};
+#define MAX_EXTENTS 128
+
+struct file_extent_cluster {
+ u64 start;
+ u64 end;
+ u64 boundary[MAX_EXTENTS];
+ unsigned int nr;
+};
+
struct reloc_control {
/* block group to relocate */
struct btrfs_block_group_cache *block_group;
@@ -2526,51 +2535,94 @@ out:
}
static noinline_for_stack
-int relocate_inode_pages(struct inode *inode, u64 start, u64 len)
+int setup_extent_mapping(struct inode *inode, u64 start, u64 end,
+ u64 block_start)
+{
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
+ struct extent_map *em;
+ int ret = 0;
+
+ em = alloc_extent_map(GFP_NOFS);
+ if (!em)
+ return -ENOMEM;
+
+ em->start = start;
+ em->len = end + 1 - start;
+ em->block_len = em->len;
+ em->block_start = block_start;
+ em->bdev = root->fs_info->fs_devices->latest_bdev;
+ set_bit(EXTENT_FLAG_PINNED, &em->flags);
+
+ lock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS);
+ while (1) {
+ spin_lock(&em_tree->lock);
+ ret = add_extent_mapping(em_tree, em);
+ spin_unlock(&em_tree->lock);
+ if (ret != -EEXIST) {
+ free_extent_map(em);
+ break;
+ }
+ btrfs_drop_extent_cache(inode, start, end, 0);
+ }
+ unlock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS);
+ return ret;
+}
+
+static int relocate_file_extent_cluster(struct inode *inode,
+ struct file_extent_cluster *cluster)
{
u64 page_start;
u64 page_end;
- unsigned long i;
- unsigned long first_index;
+ u64 offset = BTRFS_I(inode)->index_cnt;
+ unsigned long index;
unsigned long last_index;
- unsigned int total_read = 0;
- unsigned int total_dirty = 0;
+ unsigned int dirty_page = 0;
struct page *page;
struct file_ra_state *ra;
- struct btrfs_ordered_extent *ordered;
- struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
+ int nr = 0;
int ret = 0;
+ if (!cluster->nr)
+ return 0;
+
ra = kzalloc(sizeof(*ra), GFP_NOFS);
if (!ra)
return -ENOMEM;
+ index = (cluster->start - offset) >> PAGE_CACHE_SHIFT;
+ last_index = (cluster->end - offset) >> PAGE_CACHE_SHIFT;
+
mutex_lock(&inode->i_mutex);
- first_index = start >> PAGE_CACHE_SHIFT;
- last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
- /* make sure the dirty trick played by the caller work */
- ret = invalidate_inode_pages2_range(inode->i_mapping,
- first_index, last_index);
+ i_size_write(inode, cluster->end + 1 - offset);
+ ret = setup_extent_mapping(inode, cluster->start - offset,
+ cluster->end - offset, cluster->start);
if (ret)
goto out_unlock;
file_ra_state_init(ra, inode->i_mapping);
- for (i = first_index ; i <= last_index; i++) {
- if (total_read % ra->ra_pages == 0) {
- btrfs_force_ra(inode->i_mapping, ra, NULL, i,
- min(last_index, ra->ra_pages + i - 1));
- }
- total_read++;
-again:
- if (((u64)i << PAGE_CACHE_SHIFT) > i_size_read(inode))
- BUG_ON(1);
- page = grab_cache_page(inode->i_mapping, i);
+ WARN_ON(cluster->start != cluster->boundary[0]);
+ while (index <= last_index) {
+ page = find_lock_page(inode->i_mapping, index);
if (!page) {
- ret = -ENOMEM;
- goto out_unlock;
+ page_cache_sync_readahead(inode->i_mapping,
+ ra, NULL, index,
+ last_index + 1 - index);
+ page = grab_cache_page(inode->i_mapping, index);
+ if (!page) {
+ ret = -ENOMEM;
+ goto out_unlock;
+ }
}
+
+ if (PageReadahead(page)) {
+ page_cache_async_readahead(inode->i_mapping,
+ ra, NULL, page, index,
+ last_index + 1 - index);
+ }
+
if (!PageUptodate(page)) {
btrfs_readpage(NULL, page);
lock_page(page);
@@ -2581,75 +2633,79 @@ again:
goto out_unlock;
}
}
- wait_on_page_writeback(page);
page_start = (u64)page->index << PAGE_CACHE_SHIFT;
page_end = page_start + PAGE_CACHE_SIZE - 1;
- lock_extent(io_tree, page_start, page_end, GFP_NOFS);
- ordered = btrfs_lookup_ordered_extent(inode, page_start);
- if (ordered) {
- unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
- unlock_page(page);
- page_cache_release(page);
- btrfs_start_ordered_extent(inode, ordered, 1);
- btrfs_put_ordered_extent(ordered);
- goto again;
- }
+ lock_extent(&BTRFS_I(inode)->io_tree,
+ page_start, page_end, GFP_NOFS);
+
set_page_extent_mapped(page);
- if (i == first_index)
- set_extent_bits(io_tree, page_start, page_end,
+ if (nr < cluster->nr &&
+ page_start + offset == cluster->boundary[nr]) {
+ set_extent_bits(&BTRFS_I(inode)->io_tree,
+ page_start, page_end,
EXTENT_BOUNDARY, GFP_NOFS);
+ nr++;
+ }
btrfs_set_extent_delalloc(inode, page_start, page_end);
set_page_dirty(page);
- total_dirty++;
+ dirty_page++;
- unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
+ unlock_extent(&BTRFS_I(inode)->io_tree,
+ page_start, page_end, GFP_NOFS);
unlock_page(page);
page_cache_release(page);
+
+ index++;
+ if (nr < cluster->nr &&
+ page_end + 1 + offset == cluster->boundary[nr]) {
+ balance_dirty_pages_ratelimited_nr(inode->i_mapping,
+ dirty_page);
+ dirty_page = 0;
+ }
}
+ if (dirty_page) {
+ balance_dirty_pages_ratelimited_nr(inode->i_mapping,
+ dirty_page);
+ }
+ WARN_ON(nr != cluster->nr);
out_unlock:
mutex_unlock(&inode->i_mutex);
kfree(ra);
- balance_dirty_pages_ratelimited_nr(inode->i_mapping, total_dirty);
return ret;
}
static noinline_for_stack
-int relocate_data_extent(struct inode *inode, struct btrfs_key *extent_key)
+int relocate_data_extent(struct inode *inode, struct btrfs_key *extent_key,
+ struct file_extent_cluster *cluster)
{
- struct btrfs_root *root = BTRFS_I(inode)->root;
- struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
- struct extent_map *em;
- u64 start = extent_key->objectid - BTRFS_I(inode)->index_cnt;
- u64 end = start + extent_key->offset - 1;
-
- em = alloc_extent_map(GFP_NOFS);
- em->start = start;
- em->len = extent_key->offset;
- em->block_len = extent_key->offset;
- em->block_start = extent_key->objectid;
- em->bdev = root->fs_info->fs_devices->latest_bdev;
- set_bit(EXTENT_FLAG_PINNED, &em->flags);
+ int ret;
- /* setup extent map to cheat btrfs_readpage */
- lock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS);
- while (1) {
- int ret;
- spin_lock(&em_tree->lock);
- ret = add_extent_mapping(em_tree, em);
- spin_unlock(&em_tree->lock);
- if (ret != -EEXIST) {
- free_extent_map(em);
- break;
- }
- btrfs_drop_extent_cache(inode, start, end, 0);
+ if (cluster->nr > 0 && extent_key->objectid !=
cluster->end + 1) {
+ ret = relocate_file_extent_cluster(inode, cluster);
+ if (ret)
+ return ret;
+ cluster->nr = 0;
}
- unlock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS);
- return relocate_inode_pages(inode, start, extent_key->offset);
+ if (!cluster->nr)
+ cluster->start = extent_key->objectid;
+ else
+ BUG_ON(cluster->nr >= MAX_EXTENTS);
+ cluster->end = extent_key->objectid + extent_key->offset - 1;
+ cluster->boundary[cluster->nr] = extent_key->objectid;
+ cluster->nr++;
+
+ if (cluster->nr >= MAX_EXTENTS) {
+ ret = relocate_file_extent_cluster(inode, cluster);
+ if (ret)
+ return ret;
+ cluster->nr = 0;
+ }
+ return 0;
}
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
@@ -3199,6 +3255,7 @@ static noinline_for_stack int relocate_b
{
struct rb_root blocks = RB_ROOT;
struct btrfs_key key;
+ struct file_extent_cluster *cluster;
struct btrfs_trans_handle *trans = NULL;
struct btrfs_path *path;
struct btrfs_extent_item *ei;
@@ -3208,6 +3265,10 @@ static noinline_for_stack int relocate_b
int ret;
int err = 0;
+ cluster = kzalloc(sizeof(*cluster), GFP_NOFS);
+ if (!cluster)
+ return -ENOMEM;
+
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
@@ -3298,14 +3359,15 @@ static noinline_for_stack int relocate_b
}
nr = trans->blocks_used;
- btrfs_end_transaction_throttle(trans, rc->extent_root);
+ btrfs_end_transaction(trans, rc->extent_root);
trans = NULL;
btrfs_btree_balance_dirty(rc->extent_root, nr);
if (rc->stage == MOVE_DATA_EXTENTS &&
(flags & BTRFS_EXTENT_FLAG_DATA)) {
rc->found_file_extent = 1;
- ret = relocate_data_extent(rc->data_inode, &key);
+ ret = relocate_data_extent(rc->data_inode,
+ &key, cluster);
if (ret < 0) {
err = ret;
break;
@@ -3320,6 +3382,14 @@ static noinline_for_stack int relocate_b
btrfs_btree_balance_dirty(rc->extent_root, nr);
}
+ if (!err) {
+ ret = relocate_file_extent_cluster(rc->data_inode, cluster);
+ if (ret < 0)
+ err = ret;
+ }
+
+ kfree(cluster);
+
rc->create_reloc_root = 0;
smp_mb();
@@ -3340,8 +3410,7 @@ static noinline_for_stack int relocate_b
}
static int __insert_orphan_inode(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- u64 objectid, u64 size)
+ struct btrfs_root *root, u64 objectid)
{
struct btrfs_path *path;
struct btrfs_inode_item *item;
@@ -3360,7 +3429,7 @@ static int __insert_orphan_inode(struct
item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item);
memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item));
btrfs_set_inode_generation(leaf, item, 1);
- btrfs_set_inode_size(leaf, item, size);
+ btrfs_set_inode_size(leaf, item, 0);
btrfs_set_inode_mode(leaf, item, S_IFREG | 0600);
btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS);
btrfs_mark_buffer_dirty(leaf);
@@ -3396,12 +3465,7 @@ static struct inode *create_reloc_inode(
if (err)
goto out;
- err = __insert_orphan_inode(trans, root, objectid, group->key.offset);
- BUG_ON(err);
-
- err = btrfs_insert_file_extent(trans, root, objectid, 0, 0, 0,
- group->key.offset, 0, group->key.offset,
- 0, 0, 0);
+ err = __insert_orphan_inode(trans, root, objectid);
BUG_ON(err);
key.objectid = objectid;
@@ -3506,10 +3570,10 @@ int btrfs_relocate_block_group(struct bt
}
}
- filemap_fdatawrite_range(fs_info->btree_inode->i_mapping,
- rc->block_group->key.objectid,
- rc->block_group->key.objectid +
- rc->block_group->key.offset - 1);
+ filemap_write_and_wait_range(fs_info->btree_inode->i_mapping,
+ rc->block_group->key.objectid,
+ rc->block_group->key.objectid +
+ rc->block_group->key.offset - 1);
WARN_ON(rc->block_group->pinned > 0);
WARN_ON(rc->block_group->reserved > 0);
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