Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable

* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: be more polite in the async caching threads
  Btrfs: preserve commit_root for async caching
This commit is contained in:
Linus Torvalds 2009-07-30 16:46:48 -07:00
commit ec6a8679fa
5 changed files with 28 additions and 12 deletions

View File

@ -825,6 +825,7 @@ struct btrfs_fs_info {
struct mutex drop_mutex;
struct mutex volume_mutex;
struct mutex tree_reloc_mutex;
struct rw_semaphore extent_commit_sem;
/*
* this protects the ordered operations list only while we are
@ -959,9 +960,6 @@ struct btrfs_root {
/* the node lock is held while changing the node pointer */
spinlock_t node_lock;
/* taken when updating the commit root */
struct rw_semaphore commit_root_sem;
struct extent_buffer *commit_root;
struct btrfs_root *log_root;
struct btrfs_root *reloc_root;

View File

@ -909,7 +909,6 @@ static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
spin_lock_init(&root->inode_lock);
mutex_init(&root->objectid_mutex);
mutex_init(&root->log_mutex);
init_rwsem(&root->commit_root_sem);
init_waitqueue_head(&root->log_writer_wait);
init_waitqueue_head(&root->log_commit_wait[0]);
init_waitqueue_head(&root->log_commit_wait[1]);
@ -1640,6 +1639,7 @@ struct btrfs_root *open_ctree(struct super_block *sb,
mutex_init(&fs_info->cleaner_mutex);
mutex_init(&fs_info->volume_mutex);
mutex_init(&fs_info->tree_reloc_mutex);
init_rwsem(&fs_info->extent_commit_sem);
btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
btrfs_init_free_cluster(&fs_info->data_alloc_cluster);

View File

@ -267,7 +267,7 @@ static int caching_kthread(void *data)
last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
again:
/* need to make sure the commit_root doesn't disappear */
down_read(&fs_info->extent_root->commit_root_sem);
down_read(&fs_info->extent_commit_sem);
/*
* We don't want to deadlock with somebody trying to allocate a new
@ -302,10 +302,11 @@ again:
else if (ret)
break;
if (need_resched()) {
if (need_resched() ||
btrfs_transaction_in_commit(fs_info)) {
btrfs_release_path(fs_info->extent_root, path);
up_read(&fs_info->extent_root->commit_root_sem);
cond_resched();
up_read(&fs_info->extent_commit_sem);
schedule_timeout(1);
goto again;
}
@ -345,7 +346,7 @@ next:
err:
btrfs_free_path(path);
up_read(&fs_info->extent_root->commit_root_sem);
up_read(&fs_info->extent_commit_sem);
atomic_dec(&block_group->space_info->caching_threads);
wake_up(&block_group->caching_q);

View File

@ -42,10 +42,8 @@ static noinline void put_transaction(struct btrfs_transaction *transaction)
static noinline void switch_commit_root(struct btrfs_root *root)
{
down_write(&root->commit_root_sem);
free_extent_buffer(root->commit_root);
root->commit_root = btrfs_root_node(root);
up_write(&root->commit_root_sem);
}
/*
@ -466,7 +464,10 @@ static int update_cowonly_root(struct btrfs_trans_handle *trans,
ret = btrfs_write_dirty_block_groups(trans, root);
BUG_ON(ret);
}
switch_commit_root(root);
if (root != root->fs_info->extent_root)
switch_commit_root(root);
return 0;
}
@ -499,6 +500,11 @@ static noinline int commit_cowonly_roots(struct btrfs_trans_handle *trans,
update_cowonly_root(trans, root);
}
down_write(&fs_info->extent_commit_sem);
switch_commit_root(fs_info->extent_root);
up_write(&fs_info->extent_commit_sem);
return 0;
}
@ -851,6 +857,16 @@ static void update_super_roots(struct btrfs_root *root)
super->root_level = root_item->level;
}
int btrfs_transaction_in_commit(struct btrfs_fs_info *info)
{
int ret = 0;
spin_lock(&info->new_trans_lock);
if (info->running_transaction)
ret = info->running_transaction->in_commit;
spin_unlock(&info->new_trans_lock);
return ret;
}
int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{

View File

@ -107,4 +107,5 @@ int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
int btrfs_write_and_wait_marked_extents(struct btrfs_root *root,
struct extent_io_tree *dirty_pages);
int btrfs_transaction_in_commit(struct btrfs_fs_info *info);
#endif