Btrfs: use signed integer instead of unsigned long integer for log transid
The log trans id is initialized to be 0 every time we create a log tree,
and the log tree need be re-created after a new transaction is started,
it means the log trans id is unlikely to be a huge number, so we can use
signed integer instead of unsigned long integer to save a bit space.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
index 8fed212..c9a2444 100644
--- a/fs/btrfs/btrfs_inode.h
+++ b/fs/btrfs/btrfs_inode.h
@@ -109,15 +109,18 @@
u64 last_trans;
/*
- * log transid when this inode was last modified
- */
- u64 last_sub_trans;
-
- /*
* transid that last logged this inode
*/
u64 logged_trans;
+ /*
+ * log transid when this inode was last modified
+ */
+ int last_sub_trans;
+
+ /* a local copy of root's last_log_commit */
+ int last_log_commit;
+
/* total number of bytes pending delalloc, used by stat to calc the
* real block usage of the file
*/
@@ -155,9 +158,6 @@
/* flags field from the on disk inode */
u32 flags;
- /* a local copy of root's last_log_commit */
- unsigned long last_log_commit;
-
/*
* Counters to keep track of the number of extent item's we may use due
* to delalloc and such. outstanding_extents is the number of extent
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index dac6653..70c03f5 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1721,8 +1721,8 @@
atomic_t log_writers;
atomic_t log_commit[2];
atomic_t log_batch;
- unsigned long log_transid;
- unsigned long last_log_commit;
+ int log_transid;
+ int last_log_commit;
pid_t log_start_pid;
bool log_multiple_pids;
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 285c168..128a904 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -2362,7 +2362,7 @@
}
static int wait_log_commit(struct btrfs_trans_handle *trans,
- struct btrfs_root *root, unsigned long transid)
+ struct btrfs_root *root, int transid)
{
DEFINE_WAIT(wait);
int index = transid % 2;
@@ -2434,7 +2434,7 @@
int ret;
struct btrfs_root *log = root->log_root;
struct btrfs_root *log_root_tree = root->fs_info->log_root_tree;
- unsigned long log_transid = 0;
+ int log_transid = 0;
struct blk_plug plug;
mutex_lock(&root->log_mutex);