We need to throttle split bio in case of IOPS limit even though the
split bio has been marked as BIO_THROTTLED since block layer
accounts split bio actually.
If only throughput throttle is setup, no need to throttle any more
if BIO_THROTTLED is set since we have accounted & considered the
whole bio bytes already.
Add one flag of THROTL_TG_HAS_IOPS_LIMIT for serving this purpose.
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
block/blk-throttle.c | 21 ++++++++++++++-------
block/blk-throttle.h | 11 +++++++++++
2 files changed, 25 insertions(+), 7 deletions(-)
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 67bb39d13751..36c17fcb67ef 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -42,11 +42,6 @@
/* A workqueue to queue throttle related work */
static struct workqueue_struct *kthrotld_workqueue;
-enum tg_state_flags {
- THROTL_TG_PENDING = 1 << 0, /* on parent's pending tree */
- THROTL_TG_WAS_EMPTY = 1 << 1, /* bio_lists[] became non-empty */
-};
-
#define rb_entry_tg(node) rb_entry((node), struct throtl_grp, rb_node)
/* We measure latency for request size from <= 4k to >= 1M */
@@ -426,12 +421,24 @@ static void tg_update_has_rules(struct throtl_grp *tg)
struct throtl_grp *parent_tg = sq_to_tg(tg->service_queue.parent_sq);
struct throtl_data *td = tg->td;
int rw;
+ int has_iops_limit = 0;
+
+ for (rw = READ; rw <= WRITE; rw++) {
+ unsigned int iops_limit = tg_iops_limit(tg, rw);
- for (rw = READ; rw <= WRITE; rw++)
tg->has_rules[rw] = (parent_tg && parent_tg->has_rules[rw]) ||
(td->limit_valid[td->limit_index] &&
(tg_bps_limit(tg, rw) != U64_MAX ||
- tg_iops_limit(tg, rw) != UINT_MAX));
+ iops_limit != UINT_MAX));
+
+ if (iops_limit != UINT_MAX)
+ has_iops_limit = 1;
+ }
+
+ if (has_iops_limit)
+ tg->flags |= THROTL_TG_HAS_IOPS_LIMIT;
+ else
+ tg->flags &= ~THROTL_TG_HAS_IOPS_LIMIT;
}
static void throtl_pd_online(struct blkg_policy_data *pd)
diff --git a/block/blk-throttle.h b/block/blk-throttle.h
index cb43f4417d6e..c996a15f290e 100644
--- a/block/blk-throttle.h
+++ b/block/blk-throttle.h
@@ -52,6 +52,12 @@ struct throtl_service_queue {
struct timer_list pending_timer; /* fires on first_pending_disptime */
};
+enum tg_state_flags {
+ THROTL_TG_PENDING = 1 << 0, /* on parent's pending tree */
+ THROTL_TG_WAS_EMPTY = 1 << 1, /* bio_lists[] became non-empty */
+ THROTL_TG_HAS_IOPS_LIMIT = 1 << 2, /* tg has iops limit */
+};
+
enum {
LIMIT_LOW,
LIMIT_MAX,
@@ -170,6 +176,11 @@ static inline bool blk_throtl_bio(struct bio *bio)
{
struct throtl_grp *tg = blkg_to_tg(bio->bi_blkg);
+ /* no need to throttle bps any more if the bio has been throttled */
+ if (bio_flagged(bio, BIO_THROTTLED) &&
+ !(tg->flags & THROTL_TG_HAS_IOPS_LIMIT))
+ return false;
+
if (!tg->has_rules[bio_data_dir(bio)])
return false;
--
2.31.1
