writeback: elevate queue_io() into wb_writeback()

Code refactor for more logical code layout.
No behavior change.

- remove the mis-named __writeback_inodes_sb()

- wb_writeback()/writeback_inodes_wb() will decide when to queue_io()
  before calling __writeback_inodes_wb()

Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
This commit is contained in:
Wu Fengguang 2011-04-21 12:06:32 -06:00
parent f758eeabeb
commit e8dfc30582

View file

@ -580,17 +580,13 @@ static int writeback_sb_inodes(struct super_block *sb, struct bdi_writeback *wb,
return 1;
}
void writeback_inodes_wb(struct bdi_writeback *wb,
static void __writeback_inodes_wb(struct bdi_writeback *wb,
struct writeback_control *wbc)
{
int ret = 0;
if (!wbc->wb_start)
wbc->wb_start = jiffies; /* livelock avoidance */
spin_lock(&wb->list_lock);
if (list_empty(&wb->b_io))
queue_io(wb, wbc->older_than_this);
while (!list_empty(&wb->b_io)) {
struct inode *inode = wb_inode(wb->b_io.prev);
@ -606,19 +602,16 @@ void writeback_inodes_wb(struct bdi_writeback *wb,
if (ret)
break;
}
spin_unlock(&wb->list_lock);
/* Leave any unwritten inodes on b_io */
}
static void __writeback_inodes_sb(struct super_block *sb,
struct bdi_writeback *wb, struct writeback_control *wbc)
void writeback_inodes_wb(struct bdi_writeback *wb,
struct writeback_control *wbc)
{
WARN_ON(!rwsem_is_locked(&sb->s_umount));
spin_lock(&wb->list_lock);
if (list_empty(&wb->b_io))
queue_io(wb, wbc->older_than_this);
writeback_sb_inodes(sb, wb, wbc, true);
__writeback_inodes_wb(wb, wbc);
spin_unlock(&wb->list_lock);
}
@ -685,7 +678,7 @@ static long wb_writeback(struct bdi_writeback *wb,
* The intended call sequence for WB_SYNC_ALL writeback is:
*
* wb_writeback()
* __writeback_inodes_sb() <== called only once
* writeback_sb_inodes() <== called only once
* write_cache_pages() <== called once for each inode
* (quickly) tag currently dirty pages
* (maybe slowly) sync all tagged pages
@ -694,6 +687,7 @@ static long wb_writeback(struct bdi_writeback *wb,
write_chunk = LONG_MAX;
wbc.wb_start = jiffies; /* livelock avoidance */
spin_lock(&wb->list_lock);
for (;;) {
/*
* Stop writeback when nr_pages has been consumed
@ -730,10 +724,12 @@ static long wb_writeback(struct bdi_writeback *wb,
wbc.inodes_written = 0;
trace_wbc_writeback_start(&wbc, wb->bdi);
if (list_empty(&wb->b_io))
queue_io(wb, wbc.older_than_this);
if (work->sb)
__writeback_inodes_sb(work->sb, wb, &wbc);
writeback_sb_inodes(work->sb, wb, &wbc, true);
else
writeback_inodes_wb(wb, &wbc);
__writeback_inodes_wb(wb, &wbc);
trace_wbc_writeback_written(&wbc, wb->bdi);
work->nr_pages -= write_chunk - wbc.nr_to_write;
@ -761,7 +757,6 @@ static long wb_writeback(struct bdi_writeback *wb,
* become available for writeback. Otherwise
* we'll just busyloop.
*/
spin_lock(&wb->list_lock);
if (!list_empty(&wb->b_more_io)) {
inode = wb_inode(wb->b_more_io.prev);
trace_wbc_writeback_wait(&wbc, wb->bdi);
@ -769,8 +764,8 @@ static long wb_writeback(struct bdi_writeback *wb,
inode_wait_for_writeback(inode, wb);
spin_unlock(&inode->i_lock);
}
spin_unlock(&wb->list_lock);
}
spin_unlock(&wb->list_lock);
return wrote;
}