btrfs: drop the commit_cycles stuff for data reservations

This was an old wart left over from how we previously did data
reservations.  Before we could have people race in and take a
reservation while we were flushing space, so we needed to make sure we
looped a few times before giving up.  Now that we're using the ticketing
infrastructure we don't have to worry about this and can drop the logic
altogether.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/space-info.c

@@ -1077,7 +1077,6 @@ static void priority_reclaim_data_space(struct btrfs_fs_info *fs_info,
 					int states_nr)
 {
 	int flush_state = 0;
-	int commit_cycles = 2;
 
 	while (!space_info->full) {
 		flush_space(fs_info, space_info, U64_MAX, ALLOC_CHUNK_FORCE);
@@ -1088,20 +1087,9 @@ static void priority_reclaim_data_space(struct btrfs_fs_info *fs_info,
 		}
 		spin_unlock(&space_info->lock);
 	}
-again:
-	while (flush_state < states_nr) {
-		u64 flush_bytes = U64_MAX;
-
-		if (!commit_cycles) {
-			if (states[flush_state] == FLUSH_DELALLOC_WAIT) {
-				flush_state++;
-				continue;
-			}
-			if (states[flush_state] == COMMIT_TRANS)
-				flush_bytes = ticket->bytes;
-		}
 
-		flush_space(fs_info, space_info, flush_bytes, states[flush_state]);
+	while (flush_state < states_nr) {
+		flush_space(fs_info, space_info, U64_MAX, states[flush_state]);
 		spin_lock(&space_info->lock);
 		if (ticket->bytes == 0) {
 			spin_unlock(&space_info->lock);
@@ -1110,11 +1098,6 @@ static void priority_reclaim_data_space(struct btrfs_fs_info *fs_info,
 		spin_unlock(&space_info->lock);
 		flush_state++;
 	}
-	if (commit_cycles) {
-		commit_cycles--;
-		flush_state = 0;
-		goto again;
-	}
 }
 
 static void wait_reserve_ticket(struct btrfs_fs_info *fs_info,