in the function cbs_dequeue_soft, when q->credits <0, [now - q->last] should be accounted for sendslope,not idleslope.
so the solution 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. because of the lack of self-defined qdisc_watchdog_func, so in the generic sch_api, add qdisc_watchdog_init_func and qdisc_watchdog_init_clockid_func, so sch_cbs can use it to define its own process. the patch is changed based on v5.4.42,and the test result as follows: the NIC is 100Mb/s ,full duplex. step1: tc qdisc add dev ens33 root cbs idleslope 75 sendslope -25 hicredit 1000000 locredit -1000000 offload 0 step2: root@ubuntu:/home/yxy/kernel/linux-stable# iperf -c 192.168.1.114 -i 1 ------------------------------------------------------------ Client connecting to 192.168.1.114, TCP port 5001 TCP window size: 246 KByte (default) ------------------------------------------------------------ [ 3] local 192.168.1.120 port 42004 connected with 192.168.1.114 port 5001 [ ID] Interval Transfer Bandwidth [ 3] 0.0- 1.0 sec 9.00 MBytes 75.5 Mbits/sec [ 3] 1.0- 2.0 sec 8.50 MBytes 71.3 Mbits/sec [ 3] 2.0- 3.0 sec 8.50 MBytes 71.3 Mbits/sec [ 3] 3.0- 4.0 sec 8.38 MBytes 70.3 Mbits/sec [ 3] 4.0- 5.0 sec 8.38 MBytes 70.3 Mbits/sec [ 3] 5.0- 6.0 sec 8.50 MBytes 71.3 Mbits/sec [ 3] 6.0- 7.0 sec 8.50 MBytes 71.3 Mbits/sec [ 3] 7.0- 8.0 sec 8.62 MBytes 72.4 Mbits/sec [ 3] 8.0- 9.0 sec 8.50 MBytes 71.3 Mbits/sec [ 3] 9.0-10.0 sec 8.62 MBytes 72.4 Mbits/sec [ 3] 0.0-10.0 sec 85.5 MBytes 71.5 Mbits/sec Signed-off-by: Xiaoyong Yan <yanxiaoyo...@gmail.com> --- include/net/pkt_sched.h | 7 +++++++ net/sched/sch_api.c | 20 ++++++++++++++++++-- net/sched/sch_cbs.c | 41 +++++++++++++++++++++++++---------------- 3 files changed, 50 insertions(+), 18 deletions(-) diff --git a/include/net/pkt_sched.h b/include/net/pkt_sched.h index 6a70845bd9ab..5fec23b15e1c 100644 --- a/include/net/pkt_sched.h +++ b/include/net/pkt_sched.h @@ -9,6 +9,7 @@ #include <net/sch_generic.h> #include <net/net_namespace.h> #include <uapi/linux/pkt_sched.h> +#include <linux/hrtimer.h> #define DEFAULT_TX_QUEUE_LEN 1000 @@ -72,6 +73,12 @@ struct qdisc_watchdog { struct Qdisc *qdisc; }; +typedef enum hrtimer_restart (*qdisc_watchdog_func_t)(struct hrtimer *timer); +void qdisc_watchdog_init_clockid_func(struct qdisc_watchdog *wd, struct Qdisc *qdisc, + clockid_t clockid,qdisc_watchdog_func_t func); +void qdisc_watchdog_init_func(struct qdisc_watchdog *wd,struct Qdisc *qdisc,qdisc_watchdog_func_t func); +enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer); + void qdisc_watchdog_init_clockid(struct qdisc_watchdog *wd, struct Qdisc *qdisc, clockid_t clockid); void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc); diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c index 50794125bf02..fea08d10c811 100644 --- a/net/sched/sch_api.c +++ b/net/sched/sch_api.c @@ -22,7 +22,6 @@ #include <linux/seq_file.h> #include <linux/kmod.h> #include <linux/list.h> -#include <linux/hrtimer.h> #include <linux/slab.h> #include <linux/hashtable.h> @@ -591,7 +590,7 @@ void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc) } EXPORT_SYMBOL(qdisc_warn_nonwc); -static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer) +enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer) { struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog, timer); @@ -602,7 +601,24 @@ static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer) return HRTIMER_NORESTART; } +EXPORT_SYMBOL(qdisc_watchdog); +void qdisc_watchdog_init_clockid_func(struct qdisc_watchdog *wd,struct Qdisc *qdisc,clockid_t clockid,qdisc_watchdog_func_t func) +{ + hrtimer_init(&wd->timer,clockid,HRTIMER_MODE_ABS_PINNED); + if(!func) + wd->timer.function = qdisc_watchdog; + else + wd->timer.function = func; + wd->qdisc = qdisc; +} +EXPORT_SYMBOL(qdisc_watchdog_init_clockid_func); + +void qdisc_watchdog_init_func(struct qdisc_watchdog *wd,struct Qdisc *qdisc,qdisc_watchdog_func_t func) +{ + qdisc_watchdog_init_clockid_func(wd,qdisc,CLOCK_MONOTONIC,func); +} +EXPORT_SYMBOL(qdisc_watchdog_init_func); void qdisc_watchdog_init_clockid(struct qdisc_watchdog *wd, struct Qdisc *qdisc, clockid_t clockid) { diff --git a/net/sched/sch_cbs.c b/net/sched/sch_cbs.c index 2eaac2ff380f..351d3927e107 100644 --- a/net/sched/sch_cbs.c +++ b/net/sched/sch_cbs.c @@ -187,21 +187,15 @@ static struct sk_buff *cbs_dequeue_soft(struct Qdisc *sch) return NULL; } if (q->credits < 0) { - credits = timediff_to_credits(now - q->last, q->idleslope); + s64 delay; + + delay = delay_from_credits(q->credits, q->idleslope); + qdisc_watchdog_schedule_ns(&q->watchdog, now + delay); - 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); - - q->last = now; + q->last = now; - return NULL; - } + return NULL; + } skb = cbs_child_dequeue(sch, qdisc); if (!skb) @@ -212,11 +206,12 @@ static struct sk_buff *cbs_dequeue_soft(struct Qdisc *sch) /* As sendslope is a negative number, this will decrease the * amount of q->credits. */ + credits = credits_from_len(len, q->sendslope, atomic64_read(&q->port_rate)); credits += q->credits; - q->credits = max_t(s64, credits, q->locredit); + q->credits = clamp_t(s64, credits, q->locredit,q->hicredit); /* Estimate of the transmission of the last byte of the packet in ns */ if (unlikely(atomic64_read(&q->port_rate) == 0)) q->last = now; @@ -323,7 +318,7 @@ static void cbs_set_port_rate(struct net_device *dev, struct cbs_sched_data *q) port_rate = speed * 1000 * BYTES_PER_KBIT; atomic64_set(&q->port_rate, port_rate); - netdev_dbg(dev, "cbs: set %s's port_rate to: %lld, linkspeed: %d\n", + netdev_dbg(dev,"cbs: set %s's port_rate to: %lld, linkspeed: %d\n", dev->name, (long long)atomic64_read(&q->port_rate), ecmd.base.speed); } @@ -396,7 +391,21 @@ static int cbs_change(struct Qdisc *sch, struct nlattr *opt, return 0; } +static enum hrtimer_restart cbs_qdisc_watchdog(struct hrtimer *timer) +{ + struct qdisc_watchdog *wd = container_of(timer,struct qdisc_watchdog,timer); + struct Qdisc *sch = wd->qdisc; + struct cbs_sched_data *q = qdisc_priv(sch); + 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; + return qdisc_watchdog(timer); +} static int cbs_init(struct Qdisc *sch, struct nlattr *opt, struct netlink_ext_ack *extack) { @@ -424,7 +433,7 @@ 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); + qdisc_watchdog_init_func(&q->watchdog, sch,cbs_qdisc_watchdog); return cbs_change(sch, opt, extack); } -- 2.25.1