author: Tejun Heo <tj@kernel.org> 2016-03-18 13:52:04 -0400
committer: Jens Axboe <axboe@fb.com> 2016-03-20 09:44:20 -0600
commit: aaf2559332ba272671bb870464a99b909b29a3a1
parent: 614a4e3773148a31f58dc174bbf578ceb63510c2
Commit Summary:
Diffstat:
1 file changed, 18 insertions, 9 deletions
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 7b9582ed26f2..fee81e8768c9 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -1339,10 +1339,10 @@ __writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
* we go e.g. from filesystem. Flusher thread uses __writeback_single_inode()
* and does more profound writeback list handling in writeback_sb_inodes().
*/
-static int
-writeback_single_inode(struct inode *inode, struct bdi_writeback *wb,
- struct writeback_control *wbc)
+static int writeback_single_inode(struct inode *inode,
+ struct writeback_control *wbc)
{
+ struct bdi_writeback *wb;
int ret = 0;
spin_lock(&inode->i_lock);
@@ -1380,7 +1380,8 @@ writeback_single_inode(struct inode *inode, struct bdi_writeback *wb,
ret = __writeback_single_inode(inode, wbc);
wbc_detach_inode(wbc);
- spin_lock(&wb->list_lock);
+
+ wb = inode_to_wb_and_lock_list(inode);
spin_lock(&inode->i_lock);
/*
* If inode is clean, remove it from writeback lists. Otherwise don't
@@ -1455,6 +1456,7 @@ static long writeback_sb_inodes(struct super_block *sb,
while (!list_empty(&wb->b_io)) {
struct inode *inode = wb_inode(wb->b_io.prev);
+ struct bdi_writeback *tmp_wb;
if (inode->i_sb != sb) {
if (work->sb) {
@@ -1545,15 +1547,23 @@ static long writeback_sb_inodes(struct super_block *sb,
cond_resched();
}
-
- spin_lock(&wb->list_lock);
+ /*
+ * Requeue @inode if still dirty. Be careful as @inode may
+ * have been switched to another wb in the meantime.
+ */
+ tmp_wb = inode_to_wb_and_lock_list(inode);
spin_lock(&inode->i_lock);
if (!(inode->i_state & I_DIRTY_ALL))
wrote++;
- requeue_inode(inode, wb, &wbc);
+ requeue_inode(inode, tmp_wb, &wbc);
inode_sync_complete(inode);
spin_unlock(&inode->i_lock);
+ if (unlikely(tmp_wb != wb)) {
+ spin_unlock(&tmp_wb->list_lock);
+ spin_lock(&wb->list_lock);
+ }
+
/*
* bail out to wb_writeback() often enough to check
* background threshold and other termination conditions.
@@ -2340,7 +2350,6 @@ EXPORT_SYMBOL(sync_inodes_sb);
*/
int write_inode_now(struct inode *inode, int sync)
{
- struct bdi_writeback *wb = &inode_to_bdi(inode)->wb;
struct writeback_control wbc = {
.nr_to_write = LONG_MAX,
.sync_mode = sync ? WB_SYNC_ALL : WB_SYNC_NONE,
@@ -2352,7 +2361,7 @@ int write_inode_now(struct inode *inode, int sync)
wbc.nr_to_write = 0;
might_sleep();
- return writeback_single_inode(inode, wb, &wbc);
+ return writeback_single_inode(inode, &wbc);
}
EXPORT_SYMBOL(write_inode_now);
@@ -2369,7 +2378,7 @@ EXPORT_SYMBOL(write_inode_now);
*/
int sync_inode(struct inode *inode, struct writeback_control *wbc)
{
- return writeback_single_inode(inode, &inode_to_bdi(inode)->wb, wbc);
+ return writeback_single_inode(inode, wbc);
}
EXPORT_SYMBOL(sync_inode);