[PATCH v2 05/12] fs: don't call ->dirty_inode for lazytime timestamp updates

Eric Biggers
2021-01-09T08:01:23Z

From: Eric Biggers <ebiggers@google.com>

There is no need to call ->dirty_inode for lazytime timestamp updates
(i.e. for __mark_inode_dirty(I_DIRTY_TIME)), since by the definition of
lazytime, filesystems must ignore these updates. Filesystems only need
to care about the updated timestamps when they expire.

Therefore, only call ->dirty_inode when I_DIRTY_INODE is set.

Based on a patch from Christoph Hellwig:
https://lore.kernel.org/r/20200325122825.1086872-4-hch@lst.de

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
fs/ext4/inode.c | 12 +-----------
fs/f2fs/super.c | 3 ---
fs/fs-writeback.c | 6 +++---
fs/gfs2/super.c | 2 --
4 files changed, 4 insertions(+), 19 deletions(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 27946882d4ce4..4cc6c7834312f 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -5933,26 +5933,16 @@ int __ext4_mark_inode_dirty(handle_t *handle, struct inode *inode,
* If the inode is marked synchronous, we don't honour that here - doing
* so would cause a commit on atime updates, which we don't bother doing.
* We handle synchronous inodes at the highest possible level.
- *
- * If only the I_DIRTY_TIME flag is set, we can skip everything. If
- * I_DIRTY_TIME and I_DIRTY_SYNC is set, the only inode fields we need
- * to copy into the on-disk inode structure are the timestamp files.
*/
void ext4_dirty_inode(struct inode *inode, int flags)
{
handle_t *handle;

- if (flags == I_DIRTY_TIME)
- return;
handle = ext4_journal_start(inode, EXT4_HT_INODE, 2);
if (IS_ERR(handle))
- goto out;
-
+ return;
ext4_mark_inode_dirty(handle, inode);
-
ext4_journal_stop(handle);
-out:
- return;
}

int ext4_change_inode_journal_flag(struct inode *inode, int val)
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index b4a07fe62d1a5..cc98dc49f4a26 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -1196,9 +1196,6 @@ static void f2fs_dirty_inode(struct inode *inode, int flags)
inode->i_ino == F2FS_META_INO(sbi))
return;

- if (flags == I_DIRTY_TIME)
- return;
-
if (is_inode_flag_set(inode, FI_AUTO_RECOVER))
clear_inode_flag(inode, FI_AUTO_RECOVER);

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index c41cb887eb7d3..b7616bbd55336 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -2255,16 +2255,16 @@ void __mark_inode_dirty(struct inode *inode, int flags)
* Don't do this for I_DIRTY_PAGES - that doesn't actually
* dirty the inode itself
*/
- if (flags & (I_DIRTY_INODE | I_DIRTY_TIME)) {
+ if (flags & I_DIRTY_INODE) {
trace_writeback_dirty_inode_start(inode, flags);

if (sb->s_op->dirty_inode)
sb->s_op->dirty_inode(inode, flags);

trace_writeback_dirty_inode(inode, flags);
- }
- if (flags & I_DIRTY_INODE)
+
flags &= ~I_DIRTY_TIME;
+ }
dirtytime = flags & I_DIRTY_TIME;

/*
diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index 2f56acc41c049..042b94288ff11 100644
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -562,8 +562,6 @@ static void gfs2_dirty_inode(struct inode *inode, int flags)
int need_endtrans = 0;
int ret;

- if (!(flags & I_DIRTY_INODE))
- return;
if (unlikely(gfs2_withdrawn(sdp)))
return;
if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
--
2.30.0