[NET_SCHED]: sch_htb: use hrtimer based watchdog

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 31 insertions, 60 deletions

diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c
index 3c3294d01041..4d84200f097b 100644
--- a/net/sched/sch_htb.c
+++ b/net/sched/sch_htb.c
@@ -128,7 +128,7 @@ struct htb_class {
         } un;
         struct rb_node node[TC_HTB_NUMPRIO];    /* node for self or feed tree */
         struct rb_node pq_node; /* node for event queue */
-        unsigned long pq_key;   /* the same type as jiffies global */
+        psched_time_t pq_key;
 
         int prio_activity;      /* for which prios are we active */
         enum htb_cmode cmode;   /* current mode of the class */
@@ -179,10 +179,7 @@ struct htb_sched {
         struct rb_root wait_pq[TC_HTB_MAXDEPTH];
 
         /* time of nearest event per level (row) */
-        unsigned long near_ev_cache[TC_HTB_MAXDEPTH];
-
-        /* cached value of jiffies in dequeue */
-        unsigned long jiffies;
+        psched_time_t near_ev_cache[TC_HTB_MAXDEPTH];
 
         /* whether we hit non-work conserving class during this dequeue; we use */
         int nwc_hit;            /* this to disable mindelay complaint in dequeue */
@@ -195,7 +192,7 @@ struct htb_sched {
 
         int rate2quantum;       /* quant = rate / rate2quantum */
         psched_time_t now;      /* cached dequeue time */
-        struct timer_list timer;        /* send delay timer */
+        struct qdisc_watchdog watchdog;
 #ifdef HTB_RATECM
         struct timer_list rttim;        /* rate computer timer */
         int recmp_bucket;       /* which hash bucket to recompute next */
@@ -342,19 +339,19 @@ static void htb_add_to_wait_tree(struct htb_sched *q,
 {
         struct rb_node **p = &q->wait_pq[cl->level].rb_node, *parent = NULL;
 
-        cl->pq_key = q->jiffies + PSCHED_US2JIFFIE(delay);
-        if (cl->pq_key == q->jiffies)
+        cl->pq_key = q->now + delay;
+        if (cl->pq_key == q->now)
                 cl->pq_key++;
 
         /* update the nearest event cache */
-        if (time_after(q->near_ev_cache[cl->level], cl->pq_key))
+        if (q->near_ev_cache[cl->level] > cl->pq_key)
                 q->near_ev_cache[cl->level] = cl->pq_key;
 
         while (*p) {
                 struct htb_class *c;
                 parent = *p;
                 c = rb_entry(parent, struct htb_class, pq_node);
-                if (time_after_eq(cl->pq_key, c->pq_key))
+                if (cl->pq_key >= c->pq_key)
                         p = &parent->rb_right;
                 else
                         p = &parent->rb_left;
@@ -679,14 +676,6 @@ static int htb_requeue(struct sk_buff *skb, struct Qdisc *sch)
         return NET_XMIT_SUCCESS;
 }
 
-static void htb_timer(unsigned long arg)
-{
-        struct Qdisc *sch = (struct Qdisc *)arg;
-        sch->flags &= ~TCQ_F_THROTTLED;
-        wmb();
-        netif_schedule(sch->dev);
-}
-
 #ifdef HTB_RATECM
 #define RT_GEN(D,R) R+=D-(R/HTB_EWMAC);D=0
 static void htb_rate_timer(unsigned long arg)
@@ -778,11 +767,11 @@ static void htb_charge_class(struct htb_sched *q, struct htb_class *cl,
 /**
  * htb_do_events - make mode changes to classes at the level
  *
- * Scans event queue for pending events and applies them. Returns jiffies to
+ * Scans event queue for pending events and applies them. Returns time of
  * next pending event (0 for no event in pq).
- * Note: Aplied are events whose have cl->pq_key <= jiffies.
+ * Note: Applied are events whose have cl->pq_key <= q->now.
  */
-static long htb_do_events(struct htb_sched *q, int level)
+static psched_time_t htb_do_events(struct htb_sched *q, int level)
 {
         int i;
 
@@ -795,9 +784,9 @@ static long htb_do_events(struct htb_sched *q, int level)
                         return 0;
 
                 cl = rb_entry(p, struct htb_class, pq_node);
-                if (time_after(cl->pq_key, q->jiffies)) {
-                        return cl->pq_key - q->jiffies;
-                }
+                if (cl->pq_key > q->now)
+                        return cl->pq_key;
+
                 htb_safe_rb_erase(p, q->wait_pq + level);
                 diff = PSCHED_TDIFF_SAFE(q->now, cl->t_c, (u32) cl->mbuffer);
                 htb_change_class_mode(q, cl, &diff);
@@ -806,7 +795,7 @@ static long htb_do_events(struct htb_sched *q, int level)
         }
         if (net_ratelimit())
                 printk(KERN_WARNING "htb: too many events !\n");
-        return HZ / 10;
+        return q->now + PSCHED_TICKS_PER_SEC / 10;
 }
 
 /* Returns class->node+prio from id-tree where classe's id is >= id. NULL
@@ -958,30 +947,12 @@ next:
         return skb;
 }
 
-static void htb_delay_by(struct Qdisc *sch, long delay)
-{
-        struct htb_sched *q = qdisc_priv(sch);
-        if (delay <= 0)
-                delay = 1;
-        if (unlikely(delay > 5 * HZ)) {
-                if (net_ratelimit())
-                        printk(KERN_INFO "HTB delay %ld > 5sec\n", delay);
-                delay = 5 * HZ;
-        }
-        /* why don't use jiffies here ? because expires can be in past */
-        mod_timer(&q->timer, q->jiffies + delay);
-        sch->flags |= TCQ_F_THROTTLED;
-        sch->qstats.overlimits++;
-}
-
 static struct sk_buff *htb_dequeue(struct Qdisc *sch)
 {
         struct sk_buff *skb = NULL;
         struct htb_sched *q = qdisc_priv(sch);
         int level;
-        long min_delay;
-
-        q->jiffies = jiffies;
+        psched_time_t next_event;
 
         /* try to dequeue direct packets as high prio (!) to minimize cpu work */
         skb = __skb_dequeue(&q->direct_queue);
@@ -995,21 +966,23 @@ static struct sk_buff *htb_dequeue(struct Qdisc *sch)
                 goto fin;
         PSCHED_GET_TIME(q->now);
 
-        min_delay = LONG_MAX;
+        next_event = q->now + 5 * PSCHED_TICKS_PER_SEC;
         q->nwc_hit = 0;
         for (level = 0; level < TC_HTB_MAXDEPTH; level++) {
                 /* common case optimization - skip event handler quickly */
                 int m;
-                long delay;
-                if (time_after_eq(q->jiffies, q->near_ev_cache[level])) {
-                        delay = htb_do_events(q, level);
-                        q->near_ev_cache[level] =
-                            q->jiffies + (delay ? delay : HZ);
+                psched_time_t event;
+
+                if (q->now >= q->near_ev_cache[level]) {
+                        event = htb_do_events(q, level);
+                        q->near_ev_cache[level] = event ? event :
+                                                          PSCHED_TICKS_PER_SEC;
                 } else
-                        delay = q->near_ev_cache[level] - q->jiffies;
+                        event = q->near_ev_cache[level];
+
+                if (event && next_event > event)
+                        next_event = event;
 
-                if (delay && min_delay > delay)
-                        min_delay = delay;
                 m = ~q->row_mask[level];
                 while (m != (int)(-1)) {
                         int prio = ffz(m);
@@ -1022,7 +995,8 @@ static struct sk_buff *htb_dequeue(struct Qdisc *sch)
                         }
                 }
         }
-        htb_delay_by(sch, min_delay > 5 * HZ ? 5 * HZ : min_delay);
+        sch->qstats.overlimits++;
+        qdisc_watchdog_schedule(&q->watchdog, next_event);
 fin:
         return skb;
 }
@@ -1075,8 +1049,7 @@ static void htb_reset(struct Qdisc *sch)
 
                 }
         }
-        sch->flags &= ~TCQ_F_THROTTLED;
-        del_timer(&q->timer);
+        qdisc_watchdog_cancel(&q->watchdog);
         __skb_queue_purge(&q->direct_queue);
         sch->q.qlen = 0;
         memset(q->row, 0, sizeof(q->row));
@@ -1113,14 +1086,12 @@ static int htb_init(struct Qdisc *sch, struct rtattr *opt)
         for (i = 0; i < TC_HTB_NUMPRIO; i++)
                 INIT_LIST_HEAD(q->drops + i);
 
-        init_timer(&q->timer);
+        qdisc_watchdog_init(&q->watchdog, sch);
         skb_queue_head_init(&q->direct_queue);
 
         q->direct_qlen = sch->dev->tx_queue_len;
         if (q->direct_qlen < 2) /* some devices have zero tx_queue_len */
                 q->direct_qlen = 2;
-        q->timer.function = htb_timer;
-        q->timer.data = (unsigned long)sch;
 
 #ifdef HTB_RATECM
         init_timer(&q->rttim);
@@ -1341,7 +1312,7 @@ static void htb_destroy(struct Qdisc *sch)
 {
         struct htb_sched *q = qdisc_priv(sch);
 
-        del_timer_sync(&q->timer);
+        qdisc_watchdog_cancel(&q->watchdog);
 #ifdef HTB_RATECM
         del_timer_sync(&q->rttim);
 #endif