in the function cbs_dequeue_soft, when q->credits< 0, (now- q->last)
should be accounted for sendslope, not idleslope.
so the solution is as follows: when q->credits is less than 0, directly
calculate delay time, activate hrtimer and when hrtimer fires, calculate
idleslope credits and update it to q->credits.
Signed-off-by: Xiaoyong Yan <yanxiaoyo...@gmail.com>
---
net/sched/sch_cbs.c | 71 ++++++++++++++++++++++++++++++---------------
1 file changed, 48 insertions(+), 23 deletions(-)
diff --git a/net/sched/sch_cbs.c b/net/sched/sch_cbs.c
index 2eaac2ff380f..b870576839d1 100644
--- a/net/sched/sch_cbs.c
+++ b/net/sched/sch_cbs.c
@@ -76,7 +76,9 @@ struct cbs_sched_data {
s32 hicredit; /* in bytes */
s64 sendslope; /* in bytes/s */
s64 idleslope; /* in bytes/s */
- struct qdisc_watchdog watchdog;
+ struct hrtimer timer;
+ struct Qdisc *sch;
+ u64 last_expires;
int (*enqueue)(struct sk_buff *skb, struct Qdisc *sch,
struct sk_buff **to_free);
struct sk_buff *(*dequeue)(struct Qdisc *sch);
@@ -84,6 +86,41 @@ struct cbs_sched_data {
struct list_head cbs_list;
};
+/* timediff is in ns, slope is in bytes/s */
+static s64 timediff_to_credits(s64 timediff, s64 slope)
+{
+ return div64_s64(timediff * slope, NSEC_PER_SEC);
+}
+
+static void cbs_timer_schedule(struct cbs_sched_data *q, u64 expires)
+{
+ if (test_bit(__QDISC_STATE_DEACTIVATED,
+ &qdisc_root_sleeping(q->sch)->state))
+ return;
+ if (q->last_expires == expires)
+ return;
+ q->last_expires = expires;
+ hrtimer_start(&q->timer,
+ ns_to_ktime(expires),
+ HRTIMER_MODE_ABS_PINNED);
+
+}
+static enum hrtimer_restart cbs_timer(struct hrtimer *timer)
+{
+ struct cbs_sched_data *q = container_of(timer, struct cbs_sched_data,
timer);
+ s64 now = ktime_get_ns();
+ s64 credits;
+
+ credits = timediff_to_credits(now- q->last, q->idleslope);
+ credits = q->credits+ credits;
+ q->credits = clamp_t(s64, credits, q->locredit, q->hicredit);
+ q->last = now;
+ rcu_read_lock();
+ __netif_schedule(qdisc_root(q->sch));
+ rcu_read_unlock();
+
+ return HRTIMER_NORESTART;
+}
static int cbs_child_enqueue(struct sk_buff *skb, struct Qdisc *sch,
struct Qdisc *child,
struct sk_buff **to_free)
@@ -135,12 +172,6 @@ static int cbs_enqueue(struct sk_buff *skb, struct Qdisc
*sch,
return q->enqueue(skb, sch, to_free);
}
-/* timediff is in ns, slope is in bytes/s */
-static s64 timediff_to_credits(s64 timediff, s64 slope)
-{
- return div64_s64(timediff * slope, NSEC_PER_SEC);
-}
-
static s64 delay_from_credits(s64 credits, s64 slope)
{
if (unlikely(slope == 0))
@@ -183,25 +214,17 @@ static struct sk_buff *cbs_dequeue_soft(struct Qdisc *sch)
/* The previous packet is still being sent */
if (now < q->last) {
- qdisc_watchdog_schedule_ns(&q->watchdog, q->last);
+ cbs_timer_schedule(q, q->last);
return NULL;
}
if (q->credits < 0) {
- credits = timediff_to_credits(now - q->last, q->idleslope);
-
- credits = q->credits + credits;
- q->credits = min_t(s64, credits, q->hicredit);
-
- if (q->credits < 0) {
- s64 delay;
-
- delay = delay_from_credits(q->credits, q->idleslope);
- qdisc_watchdog_schedule_ns(&q->watchdog, now + delay);
+ s64 delay;
- q->last = now;
+ delay = delay_from_credits(q->credits, q->idleslope);
+ cbs_timer_schedule(q, now+ delay);
+ q->last = now;
- return NULL;
- }
+ return NULL;
}
skb = cbs_child_dequeue(sch, qdisc);
if (!skb)
@@ -424,7 +447,9 @@ static int cbs_init(struct Qdisc *sch, struct nlattr *opt,
q->enqueue = cbs_enqueue_soft;
q->dequeue = cbs_dequeue_soft;
- qdisc_watchdog_init(&q->watchdog, sch);
+ hrtimer_init(&q->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED);
+ q->timer.function = cbs_timer;
+ q->sch = sch;
return cbs_change(sch, opt, extack);
}
@@ -438,7 +463,7 @@ static void cbs_destroy(struct Qdisc *sch)
if (!q->qdisc)
return;
- qdisc_watchdog_cancel(&q->watchdog);
+ hrtimer_cancel(&q->timer);
cbs_disable_offload(dev, q);
spin_lock(&cbs_list_lock);
--
2.25.1
