ext3: Update ctime in ext3_splice_branch() only when needed

Currently ext3 updates ctime in ext3_splice_branch() which is called whenever
we allocate one block. But it is wasteful because ext3 doesn't support
nanosecond timestamp. This leads to a performance loss.

Signed-off-by: Kazuya Mio <k-mio@sx.jp.nec.com>
Signed-off-by: Jan Kara <jack@suse.cz>

1 files changed, 6 insertions, 3 deletions

diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index 2d0afeca0b47..6d3418662b54 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -756,6 +756,7 @@ static int ext3_splice_branch(handle_t *handle, struct inode *inode,
         struct ext3_block_alloc_info *block_i;
         ext3_fsblk_t current_block;
         struct ext3_inode_info *ei = EXT3_I(inode);
+        struct timespec now;
 
         block_i = ei->i_block_alloc_info;
         /*
@@ -795,9 +796,11 @@ static int ext3_splice_branch(handle_t *handle, struct inode *inode,
         }
 
         /* We are done with atomic stuff, now do the rest of housekeeping */
-
-        inode->i_ctime = CURRENT_TIME_SEC;
-        ext3_mark_inode_dirty(handle, inode);
+        now = CURRENT_TIME_SEC;
+        if (!timespec_equal(&inode->i_ctime, &now) || !where->bh) {
+                inode->i_ctime = now;
+                ext3_mark_inode_dirty(handle, inode);
+        }
         /* ext3_mark_inode_dirty already updated i_sync_tid */
         atomic_set(&ei->i_datasync_tid, handle->h_transaction->t_tid);