fs: inode split IO and LRU lists
The use of the same inode list structure (inode->i_list) for two
different list constructs with different lifecycles and purposes
makes it impossible to separate the locking of the different
operations. Therefore, to enable the separation of the locking of
the writeback and reclaim lists, split the inode->i_list into two
separate lists dedicated to their specific tracking functions.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index e8f6529..7a24cc9 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -79,6 +79,11 @@
return sb->s_bdi;
}
+static inline struct inode *wb_inode(struct list_head *head)
+{
+ return list_entry(head, struct inode, i_wb_list);
+}
+
static void bdi_queue_work(struct backing_dev_info *bdi,
struct wb_writeback_work *work)
{
@@ -172,11 +177,11 @@
if (!list_empty(&wb->b_dirty)) {
struct inode *tail;
- tail = list_entry(wb->b_dirty.next, struct inode, i_list);
+ tail = wb_inode(wb->b_dirty.next);
if (time_before(inode->dirtied_when, tail->dirtied_when))
inode->dirtied_when = jiffies;
}
- list_move(&inode->i_list, &wb->b_dirty);
+ list_move(&inode->i_wb_list, &wb->b_dirty);
}
/*
@@ -186,7 +191,7 @@
{
struct bdi_writeback *wb = &inode_to_bdi(inode)->wb;
- list_move(&inode->i_list, &wb->b_more_io);
+ list_move(&inode->i_wb_list, &wb->b_more_io);
}
static void inode_sync_complete(struct inode *inode)
@@ -227,14 +232,14 @@
int do_sb_sort = 0;
while (!list_empty(delaying_queue)) {
- inode = list_entry(delaying_queue->prev, struct inode, i_list);
+ inode = wb_inode(delaying_queue->prev);
if (older_than_this &&
inode_dirtied_after(inode, *older_than_this))
break;
if (sb && sb != inode->i_sb)
do_sb_sort = 1;
sb = inode->i_sb;
- list_move(&inode->i_list, &tmp);
+ list_move(&inode->i_wb_list, &tmp);
}
/* just one sb in list, splice to dispatch_queue and we're done */
@@ -245,12 +250,11 @@
/* Move inodes from one superblock together */
while (!list_empty(&tmp)) {
- inode = list_entry(tmp.prev, struct inode, i_list);
- sb = inode->i_sb;
+ sb = wb_inode(tmp.prev)->i_sb;
list_for_each_prev_safe(pos, node, &tmp) {
- inode = list_entry(pos, struct inode, i_list);
+ inode = wb_inode(pos);
if (inode->i_sb == sb)
- list_move(&inode->i_list, dispatch_queue);
+ list_move(&inode->i_wb_list, dispatch_queue);
}
}
}
@@ -414,7 +418,7 @@
* a reference to the inode or it's on it's way out.
* No need to add it back to the LRU.
*/
- list_del_init(&inode->i_list);
+ list_del_init(&inode->i_wb_list);
}
}
inode_sync_complete(inode);
@@ -462,8 +466,7 @@
{
while (!list_empty(&wb->b_io)) {
long pages_skipped;
- struct inode *inode = list_entry(wb->b_io.prev,
- struct inode, i_list);
+ struct inode *inode = wb_inode(wb->b_io.prev);
if (inode->i_sb != sb) {
if (only_this_sb) {
@@ -533,8 +536,7 @@
queue_io(wb, wbc->older_than_this);
while (!list_empty(&wb->b_io)) {
- struct inode *inode = list_entry(wb->b_io.prev,
- struct inode, i_list);
+ struct inode *inode = wb_inode(wb->b_io.prev);
struct super_block *sb = inode->i_sb;
if (!pin_sb_for_writeback(sb)) {
@@ -672,8 +674,7 @@
*/
spin_lock(&inode_lock);
if (!list_empty(&wb->b_more_io)) {
- inode = list_entry(wb->b_more_io.prev,
- struct inode, i_list);
+ inode = wb_inode(wb->b_more_io.prev);
trace_wbc_writeback_wait(&wbc, wb->bdi);
inode_wait_for_writeback(inode);
}
@@ -987,7 +988,7 @@
}
inode->dirtied_when = jiffies;
- list_move(&inode->i_list, &bdi->wb.b_dirty);
+ list_move(&inode->i_wb_list, &bdi->wb.b_dirty);
}
}
out: