[4.4,9/9] ext4: avoid unnecessary stalls in ext4_evict_inode()

Message ID 20191122105113.11213-9-lee.jones@linaro.org
State Superseded
Headers show
  • [4.4,1/9] ARM: 8904/1: skip nomap memblocks while finding the lowmem/highmem boundary
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Commit Message

Lee Jones Nov. 22, 2019, 10:51 a.m.
From: Jan Kara <jack@suse.cz>

[ Upstream commit 3abb1a0fc2871f2db52199e1748a1d48a54a3427 ]

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>

Signed-off-by: Lee Jones <lee.jones@linaro.org>

 fs/ext4/inode.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)



diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 3557c5717c8d..821349149726 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -212,7 +212,8 @@  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;