Btrfs: Replace the transaction work queue with kthreads

This creates one kthread for commits and one kthread for
deleting old snapshots.  All the work queues are removed.

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

1 files changed, 2 insertions, 70 deletions

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 69ed5f85a387..0c53ff775b92 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -29,8 +29,6 @@ static int total_trans = 0;
 extern struct kmem_cache *btrfs_trans_handle_cachep;
 extern struct kmem_cache *btrfs_transaction_cachep;
 
-static struct workqueue_struct *trans_wq;
-
 #define BTRFS_ROOT_TRANS_TAG 0
 #define BTRFS_ROOT_DEFRAG_TAG 1
 
@@ -807,81 +805,15 @@ int btrfs_clean_old_snapshots(struct btrfs_root *root)
 {
         struct list_head dirty_roots;
         INIT_LIST_HEAD(&dirty_roots);
-
+again:
         mutex_lock(&root->fs_info->trans_mutex);
         list_splice_init(&root->fs_info->dead_roots, &dirty_roots);
         mutex_unlock(&root->fs_info->trans_mutex);
 
         if (!list_empty(&dirty_roots)) {
                 drop_dirty_roots(root, &dirty_roots);
+                goto again;
         }
         return 0;
 }
-#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
-void btrfs_transaction_cleaner(void *p)
-#else
-void btrfs_transaction_cleaner(struct work_struct *work)
-#endif
-{
-#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
-        struct btrfs_fs_info *fs_info = p;
-#else
-        struct btrfs_fs_info *fs_info = container_of(work,
-                                                     struct btrfs_fs_info,
-                                                     trans_work.work);
-
-#endif
-        struct btrfs_root *root = fs_info->tree_root;
-        struct btrfs_transaction *cur;
-        struct btrfs_trans_handle *trans;
-        unsigned long now;
-        unsigned long delay = HZ * 30;
-        int ret;
-
-        smp_mb();
-        if (root->fs_info->closing)
-                goto out;
-
-        mutex_lock(&root->fs_info->trans_mutex);
-        cur = root->fs_info->running_transaction;
-        if (!cur) {
-                mutex_unlock(&root->fs_info->trans_mutex);
-                goto out;
-        }
-        now = get_seconds();
-        if (now < cur->start_time || now - cur->start_time < 30) {
-                mutex_unlock(&root->fs_info->trans_mutex);
-                delay = HZ * 5;
-                goto out;
-        }
-        mutex_unlock(&root->fs_info->trans_mutex);
-        btrfs_defrag_dirty_roots(root->fs_info);
-        trans = btrfs_start_transaction(root, 1);
-        ret = btrfs_commit_transaction(trans, root);
-out:
-        btrfs_clean_old_snapshots(root);
-        btrfs_transaction_queue_work(root, delay);
-}
-
-void btrfs_transaction_queue_work(struct btrfs_root *root, int delay)
-{
-        if (!root->fs_info->closing)
-                queue_delayed_work(trans_wq, &root->fs_info->trans_work, delay);
-}
-
-void btrfs_transaction_flush_work(struct btrfs_root *root)
-{
-        cancel_delayed_work(&root->fs_info->trans_work);
-        flush_workqueue(trans_wq);
-}
-
-void __init btrfs_init_transaction_sys(void)
-{
-        trans_wq = create_workqueue("btrfs-transaction");
-}
-
-void btrfs_exit_transaction_sys(void)
-{
-        destroy_workqueue(trans_wq);
-}