Commit 482cf79c authored by Tejun Heo's avatar Tejun Heo Committed by Jens Axboe

writeback, blkcg: propagate non-root blkcg congestion state

Now that bdi layer can handle per-blkcg bdi_writeback_congested state,
blk_{set|clear}_congested() can propagate non-root blkcg congestion
state to them.

This can be easily achieved by disabling the root_rl tests in
blk_{set|clear}_congested().  Note that we still need those tests when
!CONFIG_CGROUP_WRITEBACK as otherwise we'll end up flipping root blkcg
wb's congestion state for events happening on other blkcgs.

v2: Updated for bdi_writeback_congested.
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: default avatarJens Axboe <axboe@fb.com>
parent d40f75a0
...@@ -65,23 +65,26 @@ static struct workqueue_struct *kblockd_workqueue; ...@@ -65,23 +65,26 @@ static struct workqueue_struct *kblockd_workqueue;
static void blk_clear_congested(struct request_list *rl, int sync) static void blk_clear_congested(struct request_list *rl, int sync)
{ {
if (rl != &rl->q->root_rl)
return;
#ifdef CONFIG_CGROUP_WRITEBACK #ifdef CONFIG_CGROUP_WRITEBACK
clear_wb_congested(rl->blkg->wb_congested, sync); clear_wb_congested(rl->blkg->wb_congested, sync);
#else #else
clear_wb_congested(rl->q->backing_dev_info.wb.congested, sync); /*
* If !CGROUP_WRITEBACK, all blkg's map to bdi->wb and we shouldn't
* flip its congestion state for events on other blkcgs.
*/
if (rl == &rl->q->root_rl)
clear_wb_congested(rl->q->backing_dev_info.wb.congested, sync);
#endif #endif
} }
static void blk_set_congested(struct request_list *rl, int sync) static void blk_set_congested(struct request_list *rl, int sync)
{ {
if (rl != &rl->q->root_rl)
return;
#ifdef CONFIG_CGROUP_WRITEBACK #ifdef CONFIG_CGROUP_WRITEBACK
set_wb_congested(rl->blkg->wb_congested, sync); set_wb_congested(rl->blkg->wb_congested, sync);
#else #else
set_wb_congested(rl->q->backing_dev_info.wb.congested, sync); /* see blk_clear_congested() */
if (rl == &rl->q->root_rl)
set_wb_congested(rl->q->backing_dev_info.wb.congested, sync);
#endif #endif
} }
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment