[PATCH 27/48] 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: Tejun Heo
Cc: Jens Axboe
Cc: Jan Kara
Cc: Vivek Goyal
---
block/blk-core.c | 15 +--
1 file changed, 9 insertions(+), 6 deletions(-)
diff --git a/block/blk-core.c b/block/blk-core.c
index cad26e3..95488fb 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -65,23 +65,26 @@ static struct workqueue_struct *kblockd_workqueue;
static void blk_clear_congested(struct request_list *rl, int sync)
{
- if (rl != >q->root_rl)
- return;
#ifdef CONFIG_CGROUP_WRITEBACK
clear_wb_congested(rl->blkg->wb_congested, sync);
#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 == >q->root_rl)
+ clear_wb_congested(rl->q->backing_dev_info.wb.congested, sync);
#endif
}
static void blk_set_congested(struct request_list *rl, int sync)
{
- if (rl != >q->root_rl)
- return;
#ifdef CONFIG_CGROUP_WRITEBACK
set_wb_congested(rl->blkg->wb_congested, sync);
#else
- set_wb_congested(rl->q->backing_dev_info.wb.congested, sync);
+ /* see blk_clear_congested() */
+ if (rl == >q->root_rl)
+ set_wb_congested(rl->q->backing_dev_info.wb.congested, sync);
#endif
}
--
2.1.0
--
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[PATCH 27/48] 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: Tejun Heo t...@kernel.org
Cc: Jens Axboe ax...@kernel.dk
Cc: Jan Kara j...@suse.cz
Cc: Vivek Goyal vgo...@redhat.com
---
block/blk-core.c | 15 +--
1 file changed, 9 insertions(+), 6 deletions(-)
diff --git a/block/blk-core.c b/block/blk-core.c
index cad26e3..95488fb 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -65,23 +65,26 @@ static struct workqueue_struct *kblockd_workqueue;
static void blk_clear_congested(struct request_list *rl, int sync)
{
- if (rl != rl-q-root_rl)
- return;
#ifdef CONFIG_CGROUP_WRITEBACK
clear_wb_congested(rl-blkg-wb_congested, sync);
#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
}
static void blk_set_congested(struct request_list *rl, int sync)
{
- if (rl != rl-q-root_rl)
- return;
#ifdef CONFIG_CGROUP_WRITEBACK
set_wb_congested(rl-blkg-wb_congested, sync);
#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
}
--
2.1.0
--
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the body of a message to majord...@vger.kernel.org
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Please read the FAQ at http://www.tux.org/lkml/
