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>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 29 insertions, 30 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 054b4475c757..309d8c08a640 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1463,10 +1463,6 @@ 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) &&
@@ -1479,11 +1475,9 @@ 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());
@@ -1495,36 +1489,40 @@ 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);
@@ -1532,10 +1530,10 @@ 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());
@@ -1917,17 +1915,18 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 
         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))
@@ -2430,15 +2429,15 @@ 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();