ext4: avoid unnecessary stalls in ext4_evict_inode()

These days inode reclaim calls evict_inode() only when it has no pages
in the mapping.  In that case it is not necessary to wait for transaction
commit in ext4_evict_inode() as there can be no pages waiting to be
committed.  So avoid unnecessary transaction waiting in that case.

We still have to keep the check for the case where ext4_evict_inode()
gets called from other paths (e.g. umount) where inode still can have
some page cache pages.

Reported-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Jan Kara 2017-06-22 23:49:46 -04:00 committed by Theodore Ts'o
parent cdb7ee4c63
commit 3abb1a0fc2

View file

@ -215,7 +215,8 @@ void ext4_evict_inode(struct inode *inode)
*/
if (inode->i_ino != EXT4_JOURNAL_INO &&
ext4_should_journal_data(inode) &&
(S_ISLNK(inode->i_mode) || S_ISREG(inode->i_mode))) {
(S_ISLNK(inode->i_mode) || S_ISREG(inode->i_mode)) &&
inode->i_data.nrpages) {
journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
tid_t commit_tid = EXT4_I(inode)->i_datasync_tid;