Yan, Zheng
2010-Apr-26 10:45 UTC
[PATCH V2 08/12] Btrfs: Introduce global metadata reservation
Reserve metadata space for extent tree, checksum tree and root tree
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
---
diff -urp 2/fs/btrfs/ctree.h 3/fs/btrfs/ctree.h
--- 2/fs/btrfs/ctree.h 2010-04-26 17:27:31.644829469 +0800
+++ 3/fs/btrfs/ctree.h 2010-04-26 17:27:31.648830941 +0800
@@ -682,21 +682,15 @@ struct btrfs_space_info {
u64 bytes_reserved; /* total bytes the allocator has reserved for
current allocations */
u64 bytes_readonly; /* total bytes that are read only */
- u64 bytes_super; /* total bytes reserved for the super blocks */
- u64 bytes_root; /* the number of bytes needed to commit a
- transaction */
+
u64 bytes_may_use; /* number of bytes that may be used for
delalloc/allocations */
- u64 bytes_delalloc; /* number of bytes currently reserved for
- delayed allocation */
u64 disk_used; /* total bytes used on disk */
int full; /* indicates that we cannot allocate any more
chunks for this space */
int force_alloc; /* set if we need to force a chunk alloc for
this space */
- int force_delalloc; /* make people start doing filemap_flush until
- we''re under a threshold */
struct list_head list;
diff -urp 2/fs/btrfs/disk-io.c 3/fs/btrfs/disk-io.c
--- 2/fs/btrfs/disk-io.c 2010-04-26 17:27:31.638850832 +0800
+++ 3/fs/btrfs/disk-io.c 2010-04-26 17:27:31.649830174 +0800
@@ -1472,10 +1472,6 @@ static int cleaner_kthread(void *arg)
struct btrfs_root *root = arg;
do {
- smp_mb();
- if (root->fs_info->closing)
- break;
-
vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
if (!(root->fs_info->sb->s_flags & MS_RDONLY) &&
@@ -1488,11 +1484,9 @@ static int cleaner_kthread(void *arg)
if (freezing(current)) {
refrigerator();
} else {
- smp_mb();
- if (root->fs_info->closing)
- break;
set_current_state(TASK_INTERRUPTIBLE);
- schedule();
+ if (!kthread_should_stop())
+ schedule();
__set_current_state(TASK_RUNNING);
}
} while (!kthread_should_stop());
@@ -1504,36 +1498,39 @@ static int transaction_kthread(void *arg
struct btrfs_root *root = arg;
struct btrfs_trans_handle *trans;
struct btrfs_transaction *cur;
+ u64 transid;
unsigned long now;
unsigned long delay;
int ret;
do {
- smp_mb();
- if (root->fs_info->closing)
- break;
-
delay = HZ * 30;
vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
- mutex_lock(&root->fs_info->transaction_kthread_mutex);
- mutex_lock(&root->fs_info->trans_mutex);
+ spin_lock(&root->fs_info->new_trans_lock);
cur = root->fs_info->running_transaction;
if (!cur) {
- mutex_unlock(&root->fs_info->trans_mutex);
+ spin_unlock(&root->fs_info->new_trans_lock);
goto sleep;
}
now = get_seconds();
- if (now < cur->start_time || now - cur->start_time < 30) {
- mutex_unlock(&root->fs_info->trans_mutex);
+ if (!cur->blocked &&
+ (now < cur->start_time || now - cur->start_time < 30)) {
+ spin_unlock(&root->fs_info->new_trans_lock);
delay = HZ * 5;
goto sleep;
}
- mutex_unlock(&root->fs_info->trans_mutex);
- trans = btrfs_join_transaction(root, 1);
- ret = btrfs_commit_transaction(trans, root);
+ transid = cur->transid;
+ spin_unlock(&root->fs_info->new_trans_lock);
+ trans = btrfs_join_transaction(root, 1);
+ if (transid == trans->transid) {
+ ret = btrfs_commit_transaction(trans, root);
+ BUG_ON(ret);
+ } else {
+ btrfs_end_transaction(trans, root);
+ }
sleep:
wake_up_process(root->fs_info->cleaner_kthread);
mutex_unlock(&root->fs_info->transaction_kthread_mutex);
@@ -1541,10 +1538,10 @@ sleep:
if (freezing(current)) {
refrigerator();
} else {
- if (root->fs_info->closing)
- break;
set_current_state(TASK_INTERRUPTIBLE);
- schedule_timeout(delay);
+ if (!kthread_should_stop() &&
+ !btrfs_transaction_blocked(root->fs_info))
+ schedule_timeout(delay);
__set_current_state(TASK_RUNNING);
}
} while (!kthread_should_stop());
@@ -1926,17 +1923,18 @@ struct btrfs_root *open_ctree(struct sup
csum_root->track_dirty = 1;
+ fs_info->generation = generation;
+ fs_info->last_trans_committed = generation;
+ fs_info->data_alloc_profile = (u64)-1;
+ fs_info->metadata_alloc_profile = (u64)-1;
+ fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
+
ret = btrfs_read_block_groups(extent_root);
if (ret) {
printk(KERN_ERR "Failed to read block groups: %d\n", ret);
goto fail_block_groups;
}
- fs_info->generation = generation;
- fs_info->last_trans_committed = generation;
- fs_info->data_alloc_profile = (u64)-1;
- fs_info->metadata_alloc_profile = (u64)-1;
- fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
"btrfs-cleaner");
if (IS_ERR(fs_info->cleaner_kthread))
@@ -2439,15 +2437,15 @@ int close_ctree(struct btrfs_root *root)
fs_info->closing = 1;
smp_mb();
- kthread_stop(root->fs_info->transaction_kthread);
- kthread_stop(root->fs_info->cleaner_kthread);
-
if (!(fs_info->sb->s_flags & MS_RDONLY)) {
ret = btrfs_commit_super(root);
if (ret)
printk(KERN_ERR "btrfs: commit super ret %d\n", ret);
}
+ kthread_stop(root->fs_info->transaction_kthread);
+ kthread_stop(root->fs_info->cleaner_kthread);
+
fs_info->closing = 2;
smp_mb();
diff -urp 2/fs/btrfs/extent-tree.c 3/fs/btrfs/extent-tree.c
--- 2/fs/btrfs/extent-tree.c 2010-04-26 17:27:31.644829469 +0800
+++ 3/fs/btrfs/extent-tree.c 2010-04-26 17:27:31.651829828 +0800
@@ -2894,10 +2894,9 @@ int btrfs_check_data_free_space(struct i
again:
/* make sure we have enough space to handle the data first */
spin_lock(&data_sinfo->lock);
- used = data_sinfo->bytes_used + data_sinfo->bytes_delalloc +
- data_sinfo->bytes_reserved + data_sinfo->bytes_pinned +
- data_sinfo->bytes_readonly + data_sinfo->bytes_may_use +
- data_sinfo->bytes_super;
+ used = data_sinfo->bytes_used + data_sinfo->bytes_reserved +
+ data_sinfo->bytes_pinned + data_sinfo->bytes_readonly +
+ data_sinfo->bytes_may_use;
if (used + bytes > data_sinfo->total_bytes) {
struct btrfs_trans_handle *trans;
@@ -2921,7 +2920,7 @@ alloc:
bytes + 2 * 1024 * 1024,
alloc_target, 0);
btrfs_end_transaction(trans, root);
- if (ret)
+ if (ret < 0)
return ret;
if (!data_sinfo) {
@@ -2944,11 +2943,10 @@ alloc:
goto again;
}
- printk(KERN_ERR "no space left, need %llu, %llu delalloc bytes"
- ", %llu bytes_used, %llu bytes_reserved, "
- "%llu bytes_pinned, %llu bytes_readonly, %llu may use "
- "%llu total\n", (unsigned long long)bytes,
- (unsigned long long)data_sinfo->bytes_delalloc,
+ printk(KERN_ERR "no space left, need %llu, %llu bytes_used, "
+ "%llu bytes_reserved, " "%llu bytes_pinned, "
+ "%llu bytes_readonly, %llu may use %llu total\n",
+ (unsigned long long)bytes,
(unsigned long long)data_sinfo->bytes_used,
(unsigned long long)data_sinfo->bytes_reserved,
(unsigned long long)data_sinfo->bytes_pinned,
@@ -3463,6 +3461,91 @@ void btrfs_block_rsv_release(struct btrf
block_rsv_release_bytes(block_rsv, global_rsv, num_bytes);
}
+/*
+ * helper to calculate size of global block reservation.
+ * the desired value is sum of space used by extent tree,
+ * checksum tree and root tree
+ */
+static u64 calc_global_metadata_size(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_space_info *sinfo;
+ u64 num_bytes;
+ u64 meta_used;
+ u64 data_used;
+ int csum_size = btrfs_super_csum_size(&fs_info->super_copy);
+#if 0
+ /*
+ * per tree used space accounting can be inaccuracy, so we
+ * can''t rely on it.
+ */
+ spin_lock(&fs_info->extent_root->accounting_lock);
+ num_bytes = btrfs_root_used(&fs_info->extent_root->root_item);
+ spin_unlock(&fs_info->extent_root->accounting_lock);
+
+ spin_lock(&fs_info->csum_root->accounting_lock);
+ num_bytes += btrfs_root_used(&fs_info->csum_root->root_item);
+ spin_unlock(&fs_info->csum_root->accounting_lock);
+
+ spin_lock(&fs_info->tree_root->accounting_lock);
+ num_bytes += btrfs_root_used(&fs_info->tree_root->root_item);
+ spin_unlock(&fs_info->tree_root->accounting_lock);
+#endif
+ sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_DATA);
+ spin_lock(&sinfo->lock);
+ data_used = sinfo->bytes_used;
+ spin_unlock(&sinfo->lock);
+
+ sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
+ spin_lock(&sinfo->lock);
+ meta_used = sinfo->bytes_used;
+ spin_unlock(&sinfo->lock);
+
+ num_bytes = (data_used >> fs_info->sb->s_blocksize_bits) *
+ csum_size * 2;
+ num_bytes += div64_u64(data_used + meta_used, 50);
+
+ if (num_bytes * 3 > meta_used)
+ num_bytes = div64_u64(meta_used, 3);
+
+ return ALIGN(num_bytes, fs_info->extent_root->leafsize << 10);
+}
+
+static void update_global_block_rsv(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
+ struct btrfs_space_info *sinfo = block_rsv->space_info;
+ u64 num_bytes;
+
+ num_bytes = calc_global_metadata_size(fs_info);
+
+ spin_lock(&block_rsv->lock);
+ spin_lock(&sinfo->lock);
+
+ block_rsv->size = num_bytes;
+
+ num_bytes = sinfo->bytes_used + sinfo->bytes_pinned +
+ sinfo->bytes_reserved + sinfo->bytes_readonly;
+
+ if (sinfo->total_bytes > num_bytes) {
+ num_bytes = sinfo->total_bytes - num_bytes;
+ block_rsv->reserved += num_bytes;
+ sinfo->bytes_reserved += num_bytes;
+ }
+
+ if (block_rsv->reserved >= block_rsv->size) {
+ num_bytes = block_rsv->reserved - block_rsv->size;
+ sinfo->bytes_reserved -= num_bytes;
+ block_rsv->reserved = block_rsv->size;
+ block_rsv->full = 1;
+ }
+#if 0
+ printk(KERN_INFO"global block rsv size %llu reserved %llu\n",
+ block_rsv->size, block_rsv->reserved);
+#endif
+ spin_unlock(&sinfo->lock);
+ spin_unlock(&block_rsv->lock);
+}
+
static void init_global_block_rsv(struct btrfs_fs_info *fs_info)
{
struct btrfs_space_info *space_info;
@@ -3472,11 +3555,36 @@ static void init_global_block_rsv(struct
fs_info->chunk_block_rsv.priority = 10;
space_info = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
+ fs_info->global_block_rsv.space_info = space_info;
+ fs_info->global_block_rsv.priority = 10;
+ fs_info->global_block_rsv.refill_used = 1;
+ fs_info->delalloc_block_rsv.space_info = space_info;
fs_info->trans_block_rsv.space_info = space_info;
fs_info->empty_block_rsv.space_info = space_info;
fs_info->empty_block_rsv.priority = 10;
+ fs_info->extent_root->block_rsv = &fs_info->global_block_rsv;
+ fs_info->csum_root->block_rsv = &fs_info->global_block_rsv;
+ fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
+ fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
+
+ btrfs_add_durable_block_rsv(fs_info, &fs_info->global_block_rsv);
+
+ btrfs_add_durable_block_rsv(fs_info, &fs_info->delalloc_block_rsv);
+
+ update_global_block_rsv(fs_info);
+}
+
+static void release_global_block_rsv(struct btrfs_fs_info *fs_info)
+{
+ block_rsv_release_bytes(&fs_info->global_block_rsv, NULL, (u64)-1);
+ WARN_ON(fs_info->delalloc_block_rsv.size > 0);
+ WARN_ON(fs_info->delalloc_block_rsv.reserved > 0);
+ WARN_ON(fs_info->trans_block_rsv.size > 0);
+ WARN_ON(fs_info->trans_block_rsv.reserved > 0);
+ WARN_ON(fs_info->chunk_block_rsv.size > 0);
+ WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
}
static u64 calc_trans_metadata_size(struct btrfs_root *root, int num_items)
@@ -3825,6 +3933,8 @@ int btrfs_prepare_extent_commit(struct b
fs_info->pinned_extents = &fs_info->freed_extents[0];
up_write(&fs_info->extent_commit_sem);
+
+ update_global_block_rsv(fs_info);
return 0;
}
@@ -4817,19 +4927,16 @@ static void dump_space_info(struct btrfs
printk(KERN_INFO "space_info has %llu free, is %sfull\n",
(unsigned long long)(info->total_bytes - info->bytes_used -
info->bytes_pinned - info->bytes_reserved -
- info->bytes_super),
+ info->bytes_readonly),
(info->full) ? "" : "not ");
- printk(KERN_INFO "space_info total=%llu, pinned=%llu,
delalloc=%llu,"
- " may_use=%llu, used=%llu, root=%llu, super=%llu,
reserved=%llu"
- "\n",
+ printk(KERN_INFO "space_info total=%llu, used=%llu, pinned=%llu, "
+ "reserved=%llu, may_use=%llu, readonly=%llu\n",
(unsigned long long)info->total_bytes,
+ (unsigned long long)info->bytes_used,
(unsigned long long)info->bytes_pinned,
- (unsigned long long)info->bytes_delalloc,
+ (unsigned long long)info->bytes_reserved,
(unsigned long long)info->bytes_may_use,
- (unsigned long long)info->bytes_used,
- (unsigned long long)info->bytes_root,
- (unsigned long long)info->bytes_super,
- (unsigned long long)info->bytes_reserved);
+ (unsigned long long)info->bytes_readonly);
spin_unlock(&info->lock);
if (!dump_block_groups)
@@ -7726,6 +7833,8 @@ int btrfs_free_block_groups(struct btrfs
*/
synchronize_rcu();
+ release_global_block_rsv(info);
+
while(!list_empty(&info->space_info)) {
space_info = list_entry(info->space_info.next,
struct btrfs_space_info,
diff -urp 2/fs/btrfs/inode.c 3/fs/btrfs/inode.c
--- 2/fs/btrfs/inode.c 2010-04-26 17:27:31.640840079 +0800
+++ 3/fs/btrfs/inode.c 2010-04-26 17:27:31.653829551 +0800
@@ -4059,7 +4059,7 @@ int btrfs_write_inode(struct inode *inod
struct btrfs_trans_handle *trans;
int ret = 0;
- if (root->fs_info->btree_inode == inode)
+ if (BTRFS_I(inode)->dummy_inode)
return 0;
if (wait) {
@@ -4080,10 +4080,19 @@ void btrfs_dirty_inode(struct inode *ino
{
struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_trans_handle *trans;
+ int ret;
+
+ if (BTRFS_I(inode)->dummy_inode)
+ return;
trans = btrfs_join_transaction(root, 1);
btrfs_set_trans_block_group(trans, inode);
- btrfs_update_inode(trans, root, inode);
+
+ ret = btrfs_update_inode(trans, root, inode);
+ if (ret)
+ printk(KERN_ERR"btrfs: fail to dirty inode %lu error %d\n",
+ inode->i_ino, ret);
+
btrfs_end_transaction(trans, root);
}
diff -urp 2/fs/btrfs/ioctl.c 3/fs/btrfs/ioctl.c
--- 2/fs/btrfs/ioctl.c 2010-04-26 17:27:31.638850832 +0800
+++ 3/fs/btrfs/ioctl.c 2010-04-26 17:27:31.654850854 +0800
@@ -1340,8 +1340,10 @@ static int btrfs_ioctl_defrag(struct fil
ret = -EPERM;
goto out;
}
- btrfs_defrag_root(root, 0);
- btrfs_defrag_root(root->fs_info->extent_root, 0);
+ ret = btrfs_defrag_root(root, 0);
+ if (ret)
+ goto out;
+ ret = btrfs_defrag_root(root->fs_info->extent_root, 0);
break;
case S_IFREG:
if (!(file->f_mode & FMODE_WRITE)) {
@@ -1371,9 +1373,11 @@ static int btrfs_ioctl_defrag(struct fil
/* the rest are all set to zero by kzalloc */
range->len = (u64)-1;
}
- btrfs_defrag_file(file, range);
+ ret = btrfs_defrag_file(file, range);
kfree(range);
break;
+ default:
+ ret = -EINVAL;
}
out:
mnt_drop_write(file->f_path.mnt);
diff -urp 2/fs/btrfs/transaction.c 3/fs/btrfs/transaction.c
--- 2/fs/btrfs/transaction.c 2010-04-26 17:27:31.638850832 +0800
+++ 3/fs/btrfs/transaction.c 2010-04-26 17:27:31.654850854 +0800
@@ -320,10 +320,36 @@ void btrfs_throttle(struct btrfs_root *r
mutex_unlock(&root->fs_info->trans_mutex);
}
+static int should_end_transaction(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
+{
+ int ret;
+ ret = btrfs_block_rsv_check(trans, root,
+ &root->fs_info->global_block_rsv, 0, 5);
+ return ret ? 1 : 0;
+}
+
+int btrfs_should_end_transaction(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
+{
+ struct btrfs_transaction *cur_trans = trans->transaction;
+ int updates;
+
+ if (cur_trans->blocked || cur_trans->delayed_refs.flushing)
+ return 1;
+
+ updates = trans->delayed_ref_updates;
+ trans->delayed_ref_updates = 0;
+ if (updates)
+ btrfs_run_delayed_refs(trans, root, updates);
+
+ return should_end_transaction(trans, root);
+}
+
static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root, int throttle)
{
- struct btrfs_transaction *cur_trans;
+ struct btrfs_transaction *cur_trans = trans->transaction;
struct btrfs_fs_info *info = root->fs_info;
int count = 0;
@@ -349,9 +375,19 @@ static int __btrfs_end_transaction(struc
btrfs_trans_release_metadata(trans, root);
+ if (!root->fs_info->open_ioctl_trans &&
+ should_end_transaction(trans, root))
+ trans->transaction->blocked = 1;
+
+ if (cur_trans->blocked && !cur_trans->in_commit) {
+ if (throttle)
+ return btrfs_commit_transaction(trans, root);
+ else
+ wake_up_process(info->transaction_kthread);
+ }
+
mutex_lock(&info->trans_mutex);
- cur_trans = info->running_transaction;
- WARN_ON(cur_trans != trans->transaction);
+ WARN_ON(cur_trans != info->running_transaction);
WARN_ON(cur_trans->num_writers < 1);
cur_trans->num_writers--;
@@ -663,30 +699,30 @@ static noinline int commit_fs_roots(stru
int btrfs_defrag_root(struct btrfs_root *root, int cacheonly)
{
struct btrfs_fs_info *info = root->fs_info;
- int ret;
struct btrfs_trans_handle *trans;
+ int ret;
unsigned long nr;
- smp_mb();
- if (root->defrag_running)
+ if (xchg(&root->defrag_running, 1))
return 0;
- trans = btrfs_start_transaction(root, 1);
+
while (1) {
- root->defrag_running = 1;
+ trans = btrfs_start_transaction(root, 0);
+ if (IS_ERR(trans))
+ return PTR_ERR(trans);
+
ret = btrfs_defrag_leaves(trans, root, cacheonly);
+
nr = trans->blocks_used;
btrfs_end_transaction(trans, root);
btrfs_btree_balance_dirty(info->tree_root, nr);
cond_resched();
- trans = btrfs_start_transaction(root, 1);
if (root->fs_info->closing || ret != -EAGAIN)
break;
}
root->defrag_running = 0;
- smp_mb();
- btrfs_end_transaction(trans, root);
- return 0;
+ return ret;
}
#if 0
@@ -923,6 +959,16 @@ int btrfs_transaction_in_commit(struct b
return ret;
}
+int btrfs_transaction_blocked(struct btrfs_fs_info *info)
+{
+ int ret = 0;
+ spin_lock(&info->new_trans_lock);
+ if (info->running_transaction)
+ ret = info->running_transaction->blocked;
+ spin_unlock(&info->new_trans_lock);
+ return ret;
+}
+
int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
diff -urp 2/fs/btrfs/transaction.h 3/fs/btrfs/transaction.h
--- 2/fs/btrfs/transaction.h 2010-04-26 17:27:31.639840497 +0800
+++ 3/fs/btrfs/transaction.h 2010-04-26 17:27:31.655839960 +0800
@@ -106,6 +106,8 @@ int btrfs_commit_transaction(struct btrf
struct btrfs_root *root);
int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
+int btrfs_should_end_transaction(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root);
void btrfs_throttle(struct btrfs_root *root);
int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
@@ -115,5 +117,6 @@ int btrfs_write_marked_extents(struct bt
struct extent_io_tree *dirty_pages, int mark);
int btrfs_wait_marked_extents(struct btrfs_root *root,
struct extent_io_tree *dirty_pages, int mark);
+int btrfs_transaction_blocked(struct btrfs_fs_info *info);
int btrfs_transaction_in_commit(struct btrfs_fs_info *info);
#endif
diff -urp 2/fs/btrfs/tree-defrag.c 3/fs/btrfs/tree-defrag.c
--- 2/fs/btrfs/tree-defrag.c 2010-04-26 17:27:31.638850832 +0800
+++ 3/fs/btrfs/tree-defrag.c 2010-04-26 17:27:31.655839960 +0800
@@ -117,13 +117,14 @@ int btrfs_defrag_leaves(struct btrfs_tra
path->nodes[1], 0,
cache_only, &last_ret,
&root->defrag_progress);
- WARN_ON(ret && ret != -EAGAIN);
+ if (ret) {
+ WARN_ON(ret == -EAGAIN);
+ goto out;
+ }
if (next_key_ret == 0) {
memcpy(&root->defrag_progress, &key, sizeof(key));
ret = -EAGAIN;
}
-
- btrfs_release_path(root, path);
out:
if (path)
btrfs_free_path(path);
--
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