lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Btrfs: Replace the big fs_mutex with a collection of other locks

Browse Source 
Extent alloctions are still protected by a large alloc_mutex.
Objectid allocations are covered by a objectid mutex
Other btree operations are protected by a lock on individual btree nodes

Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Chris Mason
2008-06-25 16:01:30 -04:00
parent 925baeddc5
commit a213501153
12 changed files with 101 additions and 165 deletions
Download Patch File Download Diff File Expand all files Collapse all files

42
fs/btrfs/transaction.c
View File

@@ -370,6 +370,7 @@ int btrfs_defrag_root(struct btrfs_root *root, int cacheonly)
struct btrfs_trans_handle *trans;
unsigned long nr;
smp_mb();
if (root->defrag_running)
return 0;
trans = btrfs_start_transaction(root, 1);
@@ -378,16 +379,15 @@ int btrfs_defrag_root(struct btrfs_root *root, int cacheonly)
ret = btrfs_defrag_leaves(trans, root, cacheonly);
nr = trans->blocks_used;
btrfs_end_transaction(trans, root);
mutex_unlock(&info->fs_mutex);
btrfs_btree_balance_dirty(info->tree_root, nr);
cond_resched();
mutex_lock(&info->fs_mutex);
trans = btrfs_start_transaction(root, 1);
if (ret != -EAGAIN)
break;
}
root->defrag_running = 0;
smp_mb();
radix_tree_tag_clear(&info->fs_roots_radix,
(unsigned long)root->root_key.objectid,
BTRFS_ROOT_DEFRAG_TAG);
@@ -435,14 +435,14 @@ static noinline int drop_dirty_roots(struct btrfs_root *tree_root,
while(!list_empty(list)) {
struct btrfs_root *root;
mutex_lock(&tree_root->fs_info->fs_mutex);
dirty = list_entry(list->next, struct dirty_root, list);
list_del_init(&dirty->list);
num_bytes = btrfs_root_used(&dirty->root->root_item);
root = dirty->latest_root;
root->fs_info->throttles++;
atomic_inc(&root->fs_info->throttles);
mutex_lock(&root->fs_info->drop_mutex);
while(1) {
trans = btrfs_start_transaction(tree_root, 1);
ret = btrfs_drop_snapshot(trans, dirty->root);
@@ -459,14 +459,16 @@ static noinline int drop_dirty_roots(struct btrfs_root *tree_root,
nr = trans->blocks_used;
ret = btrfs_end_transaction(trans, tree_root);
BUG_ON(ret);
mutex_unlock(&tree_root->fs_info->fs_mutex);
mutex_unlock(&root->fs_info->drop_mutex);
btrfs_btree_balance_dirty(tree_root, nr);
cond_resched();
mutex_lock(&tree_root->fs_info->fs_mutex);
mutex_lock(&root->fs_info->drop_mutex);
}
BUG_ON(ret);
root->fs_info->throttles--;
atomic_dec(&root->fs_info->throttles);
mutex_lock(&root->fs_info->alloc_mutex);
num_bytes -= btrfs_root_used(&dirty->root->root_item);
bytes_used = btrfs_root_used(&root->root_item);
if (num_bytes) {
@@ -474,11 +476,15 @@ static noinline int drop_dirty_roots(struct btrfs_root *tree_root,
btrfs_set_root_used(&root->root_item,
bytes_used - num_bytes);
}
mutex_unlock(&root->fs_info->alloc_mutex);
ret = btrfs_del_root(trans, tree_root, &dirty->root->root_key);
if (ret) {
BUG();
break;
}
mutex_unlock(&root->fs_info->drop_mutex);
nr = trans->blocks_used;
ret = btrfs_end_transaction(trans, tree_root);
BUG_ON(ret);
@@ -486,7 +492,6 @@ static noinline int drop_dirty_roots(struct btrfs_root *tree_root,
free_extent_buffer(dirty->root->node);
kfree(dirty->root);
kfree(dirty);
mutex_unlock(&tree_root->fs_info->fs_mutex);
btrfs_btree_balance_dirty(tree_root, nr);
cond_resched();
@@ -503,7 +508,7 @@ int btrfs_write_ordered_inodes(struct btrfs_trans_handle *trans,
u64 objectid = 0;
int ret;
root->fs_info->throttles++;
atomic_inc(&root->fs_info->throttles);
while(1) {
ret = btrfs_find_first_ordered_inode(
&cur_trans->ordered_inode_tree,
@@ -512,7 +517,6 @@ int btrfs_write_ordered_inodes(struct btrfs_trans_handle *trans,
break;
mutex_unlock(&root->fs_info->trans_mutex);
mutex_unlock(&root->fs_info->fs_mutex);
if (S_ISREG(inode->i_mode)) {
atomic_inc(&BTRFS_I(inode)->ordered_writeback);
@@ -521,7 +525,6 @@ int btrfs_write_ordered_inodes(struct btrfs_trans_handle *trans,
}
iput(inode);
mutex_lock(&root->fs_info->fs_mutex);
mutex_lock(&root->fs_info->trans_mutex);
}
while(1) {
@@ -533,7 +536,6 @@ int btrfs_write_ordered_inodes(struct btrfs_trans_handle *trans,
if (!ret)
break;
mutex_unlock(&root->fs_info->trans_mutex);
mutex_unlock(&root->fs_info->fs_mutex);
if (S_ISREG(inode->i_mode)) {
atomic_inc(&BTRFS_I(inode)->ordered_writeback);
@@ -543,10 +545,9 @@ int btrfs_write_ordered_inodes(struct btrfs_trans_handle *trans,
atomic_dec(&inode->i_count);
iput(inode);
mutex_lock(&root->fs_info->fs_mutex);
mutex_lock(&root->fs_info->trans_mutex);
}
root->fs_info->throttles--;
atomic_dec(&root->fs_info->throttles);
return 0;
}
@@ -661,7 +662,6 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
mutex_unlock(&root->fs_info->trans_mutex);
btrfs_end_transaction(trans, root);
mutex_unlock(&root->fs_info->fs_mutex);
ret = wait_for_commit(root, cur_trans);
BUG_ON(ret);
@@ -669,7 +669,6 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
put_transaction(cur_trans);
mutex_unlock(&root->fs_info->trans_mutex);
mutex_lock(&root->fs_info->fs_mutex);
return 0;
}
@@ -687,12 +686,10 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
struct btrfs_transaction, list);
if (!prev_trans->commit_done) {
prev_trans->use_count++;
mutex_unlock(&root->fs_info->fs_mutex);
mutex_unlock(&root->fs_info->trans_mutex);
wait_for_commit(root, prev_trans);
mutex_lock(&root->fs_info->fs_mutex);
mutex_lock(&root->fs_info->trans_mutex);
put_transaction(prev_trans);
}
@@ -709,12 +706,10 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
else
timeout = 1;
mutex_unlock(&root->fs_info->fs_mutex);
mutex_unlock(&root->fs_info->trans_mutex);
schedule_timeout(timeout);
mutex_lock(&root->fs_info->fs_mutex);
mutex_lock(&root->fs_info->trans_mutex);
finish_wait(&cur_trans->writer_wait, &wait);
ret = btrfs_write_ordered_inodes(trans, root);
@@ -755,12 +750,10 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
btrfs_copy_pinned(root, pinned_copy);
mutex_unlock(&root->fs_info->trans_mutex);
mutex_unlock(&root->fs_info->fs_mutex);
ret = btrfs_write_and_wait_transaction(trans, root);
BUG_ON(ret);
write_ctree_super(trans, root);
mutex_lock(&root->fs_info->fs_mutex);
btrfs_finish_extent_commit(trans, root, pinned_copy);
mutex_lock(&root->fs_info->trans_mutex);
@@ -781,9 +774,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
kmem_cache_free(btrfs_trans_handle_cachep, trans);
if (root->fs_info->closing) {
mutex_unlock(&root->fs_info->fs_mutex);
drop_dirty_roots(root->fs_info->tree_root, &dirty_fs_roots);
mutex_lock(&root->fs_info->fs_mutex);
}
return ret;
}
@@ -823,7 +814,7 @@ void btrfs_transaction_cleaner(struct work_struct *work)
unsigned long delay = HZ * 30;
int ret;
mutex_lock(&root->fs_info->fs_mutex);
smp_mb();
if (root->fs_info->closing)
goto out;
@@ -844,7 +835,6 @@ void btrfs_transaction_cleaner(struct work_struct *work)
trans = btrfs_start_transaction(root, 1);
ret = btrfs_commit_transaction(trans, root);
out:
mutex_unlock(&root->fs_info->fs_mutex);
btrfs_clean_old_snapshots(root);
btrfs_transaction_queue_work(root, delay);
}