Btrfs: restructure btrfs_run_defrag_inodes()

This patch restructure btrfs_run_defrag_inodes() and make the code of the auto
defragment more readable.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
This commit is contained in:
Miao Xie 2012-11-26 09:26:20 +00:00 committed by Chris Mason
parent 8ddc473433
commit 26176e7c2a
3 changed files with 110 additions and 92 deletions

View File

@ -3510,6 +3510,7 @@ void btrfs_auto_defrag_exit(void);
int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
struct inode *inode);
int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info);
void btrfs_cleanup_defrag_inodes(struct btrfs_fs_info *fs_info);
int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync);
void btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
int skip_pinned);

View File

@ -3329,7 +3329,7 @@ int close_ctree(struct btrfs_root *root)
(atomic_read(&fs_info->defrag_running) == 0));
/* clear out the rbtree of defraggable inodes */
btrfs_run_defrag_inodes(fs_info);
btrfs_cleanup_defrag_inodes(fs_info);
if (!(fs_info->sb->s_flags & MS_RDONLY)) {
ret = btrfs_commit_super(root);

View File

@ -216,11 +216,11 @@ out:
}
/*
* must be called with the defrag_inodes lock held
* pick the defragable inode that we want, if it doesn't exist, we will get
* the next one.
*/
struct inode_defrag *btrfs_find_defrag_inode(struct btrfs_fs_info *info,
u64 root, u64 ino,
struct rb_node **next)
static struct inode_defrag *
btrfs_pick_defrag_inode(struct btrfs_fs_info *fs_info, u64 root, u64 ino)
{
struct inode_defrag *entry = NULL;
struct inode_defrag tmp;
@ -231,7 +231,8 @@ struct inode_defrag *btrfs_find_defrag_inode(struct btrfs_fs_info *info,
tmp.ino = ino;
tmp.root = root;
p = info->defrag_inodes.rb_node;
spin_lock(&fs_info->defrag_inodes_lock);
p = fs_info->defrag_inodes.rb_node;
while (p) {
parent = p;
entry = rb_entry(parent, struct inode_defrag, rb_node);
@ -242,17 +243,106 @@ struct inode_defrag *btrfs_find_defrag_inode(struct btrfs_fs_info *info,
else if (ret > 0)
p = parent->rb_right;
else
return entry;
goto out;
}
if (next) {
while (parent && __compare_inode_defrag(&tmp, entry) > 0) {
parent = rb_next(parent);
if (parent && __compare_inode_defrag(&tmp, entry) > 0) {
parent = rb_next(parent);
if (parent)
entry = rb_entry(parent, struct inode_defrag, rb_node);
}
*next = parent;
else
entry = NULL;
}
return NULL;
out:
if (entry)
rb_erase(parent, &fs_info->defrag_inodes);
spin_unlock(&fs_info->defrag_inodes_lock);
return entry;
}
void btrfs_cleanup_defrag_inodes(struct btrfs_fs_info *fs_info)
{
struct inode_defrag *defrag;
struct rb_node *node;
spin_lock(&fs_info->defrag_inodes_lock);
node = rb_first(&fs_info->defrag_inodes);
while (node) {
rb_erase(node, &fs_info->defrag_inodes);
defrag = rb_entry(node, struct inode_defrag, rb_node);
kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
if (need_resched()) {
spin_unlock(&fs_info->defrag_inodes_lock);
cond_resched();
spin_lock(&fs_info->defrag_inodes_lock);
}
node = rb_first(&fs_info->defrag_inodes);
}
spin_unlock(&fs_info->defrag_inodes_lock);
}
#define BTRFS_DEFRAG_BATCH 1024
static int __btrfs_run_defrag_inode(struct btrfs_fs_info *fs_info,
struct inode_defrag *defrag)
{
struct btrfs_root *inode_root;
struct inode *inode;
struct btrfs_key key;
struct btrfs_ioctl_defrag_range_args range;
int num_defrag;
/* get the inode */
key.objectid = defrag->root;
btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
key.offset = (u64)-1;
inode_root = btrfs_read_fs_root_no_name(fs_info, &key);
if (IS_ERR(inode_root)) {
kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
return PTR_ERR(inode_root);
}
key.objectid = defrag->ino;
btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
key.offset = 0;
inode = btrfs_iget(fs_info->sb, &key, inode_root, NULL);
if (IS_ERR(inode)) {
kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
return PTR_ERR(inode);
}
/* do a chunk of defrag */
clear_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags);
memset(&range, 0, sizeof(range));
range.len = (u64)-1;
range.start = defrag->last_offset;
num_defrag = btrfs_defrag_file(inode, NULL, &range, defrag->transid,
BTRFS_DEFRAG_BATCH);
/*
* if we filled the whole defrag batch, there
* must be more work to do. Queue this defrag
* again
*/
if (num_defrag == BTRFS_DEFRAG_BATCH) {
defrag->last_offset = range.start;
btrfs_requeue_inode_defrag(inode, defrag);
} else if (defrag->last_offset && !defrag->cycled) {
/*
* we didn't fill our defrag batch, but
* we didn't start at zero. Make sure we loop
* around to the start of the file.
*/
defrag->last_offset = 0;
defrag->cycled = 1;
btrfs_requeue_inode_defrag(inode, defrag);
} else {
kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
}
iput(inode);
return 0;
}
/*
@ -262,32 +352,19 @@ struct inode_defrag *btrfs_find_defrag_inode(struct btrfs_fs_info *info,
int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info)
{
struct inode_defrag *defrag;
struct btrfs_root *inode_root;
struct inode *inode;
struct rb_node *n;
struct btrfs_key key;
struct btrfs_ioctl_defrag_range_args range;
u64 first_ino = 0;
u64 root_objectid = 0;
int num_defrag;
int defrag_batch = 1024;
memset(&range, 0, sizeof(range));
range.len = (u64)-1;
atomic_inc(&fs_info->defrag_running);
spin_lock(&fs_info->defrag_inodes_lock);
while(1) {
n = NULL;
if (!__need_auto_defrag(fs_info->tree_root))
break;
/* find an inode to defrag */
defrag = btrfs_find_defrag_inode(fs_info, root_objectid,
first_ino, &n);
defrag = btrfs_pick_defrag_inode(fs_info, root_objectid,
first_ino);
if (!defrag) {
if (n) {
defrag = rb_entry(n, struct inode_defrag,
rb_node);
} else if (root_objectid || first_ino) {
if (root_objectid || first_ino) {
root_objectid = 0;
first_ino = 0;
continue;
@ -296,71 +373,11 @@ int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info)
}
}
/* remove it from the rbtree */
first_ino = defrag->ino + 1;
root_objectid = defrag->root;
rb_erase(&defrag->rb_node, &fs_info->defrag_inodes);
if (btrfs_fs_closing(fs_info))
goto next_free;
spin_unlock(&fs_info->defrag_inodes_lock);
/* get the inode */
key.objectid = defrag->root;
btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
key.offset = (u64)-1;
inode_root = btrfs_read_fs_root_no_name(fs_info, &key);
if (IS_ERR(inode_root))
goto next;
key.objectid = defrag->ino;
btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
key.offset = 0;
inode = btrfs_iget(fs_info->sb, &key, inode_root, NULL);
if (IS_ERR(inode))
goto next;
/* do a chunk of defrag */
clear_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags);
range.start = defrag->last_offset;
num_defrag = btrfs_defrag_file(inode, NULL, &range, defrag->transid,
defrag_batch);
/*
* if we filled the whole defrag batch, there
* must be more work to do. Queue this defrag
* again
*/
if (num_defrag == defrag_batch) {
defrag->last_offset = range.start;
btrfs_requeue_inode_defrag(inode, defrag);
/*
* we don't want to kfree defrag, we added it back to
* the rbtree
*/
defrag = NULL;
} else if (defrag->last_offset && !defrag->cycled) {
/*
* we didn't fill our defrag batch, but
* we didn't start at zero. Make sure we loop
* around to the start of the file.
*/
defrag->last_offset = 0;
defrag->cycled = 1;
btrfs_requeue_inode_defrag(inode, defrag);
defrag = NULL;
}
iput(inode);
next:
spin_lock(&fs_info->defrag_inodes_lock);
next_free:
if (defrag)
kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
__btrfs_run_defrag_inode(fs_info, defrag);
}
spin_unlock(&fs_info->defrag_inodes_lock);
atomic_dec(&fs_info->defrag_running);
/*