Merge branch 'pxa-tosa' into pxa

[linux-2.6-omap-h63xx.git] / net / sched / sch_htb.c

diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c
index 795c761ad99fb4cc07d61f79a327061f895c69c8..6807c97985a54adac52ceb42d4b3847e0beebdd2 100644 (file)
--- a/net/sched/sch_htb.c
+++ b/net/sched/sch_htb.c
@@ -28,6 +28,7 @@
  * $Id: sch_htb.c,v 1.25 2003/12/07 11:08:25 devik Exp devik $
  */
 #include <linux/module.h>
+#include <linux/moduleparam.h>
 #include <linux/types.h>
 #include <linux/kernel.h>
 #include <linux/string.h>
@@ -53,13 +54,17 @@
 */
 
 #define HTB_HSIZE 16           /* classid hash size */
-#define HTB_HYSTERESIS 1       /* whether to use mode hysteresis for speedup */
+static int htb_hysteresis __read_mostly = 0; /* whether to use mode hysteresis for speedup */
 #define HTB_VER 0x30011                /* major must be matched with number suplied by TC as version */
 
 #if HTB_VER >> 16 != TC_HTB_PROTOVER
 #error "Mismatched sch_htb.c and pkt_sch.h"
 #endif
 
+/* Module parameter and sysfs export */
+module_param    (htb_hysteresis, int, 0640);
+MODULE_PARM_DESC(htb_hysteresis, "Hysteresis mode, less CPU load, less accurate");
+
 /* used internaly to keep status of single class */
 enum htb_cmode {
        HTB_CANT_SEND,          /* class can't send and can't borrow */
@@ -462,19 +467,21 @@ static void htb_deactivate_prios(struct htb_sched *q, struct htb_class *cl)
                htb_remove_class_from_row(q, cl, mask);
 }
 
-#if HTB_HYSTERESIS
 static inline long htb_lowater(const struct htb_class *cl)
 {
-       return cl->cmode != HTB_CANT_SEND ? -cl->cbuffer : 0;
+       if (htb_hysteresis)
+               return cl->cmode != HTB_CANT_SEND ? -cl->cbuffer : 0;
+       else
+               return 0;
 }
 static inline long htb_hiwater(const struct htb_class *cl)
 {
-       return cl->cmode == HTB_CAN_SEND ? -cl->buffer : 0;
+       if (htb_hysteresis)
+               return cl->cmode == HTB_CAN_SEND ? -cl->buffer : 0;
+       else
+               return 0;
 }
-#else
-#define htb_lowater(cl)        (0)
-#define htb_hiwater(cl)        (0)
-#endif
+
 
 /**
  * htb_class_mode - computes and returns current class mode
@@ -711,9 +718,11 @@ static void htb_charge_class(struct htb_sched *q, struct htb_class *cl,
  */
 static psched_time_t htb_do_events(struct htb_sched *q, int level)
 {
-       int i;
-
-       for (i = 0; i < 500; i++) {
+       /* don't run for longer than 2 jiffies; 2 is used instead of
+          1 to simplify things when jiffy is going to be incremented
+          too soon */
+       unsigned long stop_at = jiffies + 2;
+       while (time_before(jiffies, stop_at)) {
                struct htb_class *cl;
                long diff;
                struct rb_node *p = rb_first(&q->wait_pq[level]);
@@ -731,9 +740,8 @@ static psched_time_t htb_do_events(struct htb_sched *q, int level)
                if (cl->cmode != HTB_CAN_SEND)
                        htb_add_to_wait_tree(q, cl, diff);
        }
-       if (net_ratelimit())
-               printk(KERN_WARNING "htb: too many events !\n");
-       return q->now + PSCHED_TICKS_PER_SEC / 10;
+       /* too much load - let's continue on next jiffie */
+       return q->now + PSCHED_TICKS_PER_SEC / HZ;
 }
 
 /* Returns class->node+prio from id-tree where classe's id is >= id. NULL
@@ -1196,12 +1204,16 @@ static inline int htb_parent_last_child(struct htb_class *cl)
        return 1;
 }
 
-static void htb_parent_to_leaf(struct htb_class *cl, struct Qdisc *new_q)
+static void htb_parent_to_leaf(struct htb_sched *q, struct htb_class *cl,
+                              struct Qdisc *new_q)
 {
        struct htb_class *parent = cl->parent;
 
        BUG_TRAP(!cl->level && cl->un.leaf.q && !cl->prio_activity);
 
+       if (parent->cmode != HTB_CAN_SEND)
+               htb_safe_rb_erase(&parent->pq_node, q->wait_pq + parent->level);
+
        parent->level = 0;
        memset(&parent->un.inner, 0, sizeof(parent->un.inner));
        INIT_LIST_HEAD(&parent->un.leaf.drop_list);
@@ -1299,7 +1311,7 @@ static int htb_delete(struct Qdisc *sch, unsigned long arg)
                htb_deactivate(q, cl);
 
        if (last_child)
-               htb_parent_to_leaf(cl, new_q);
+               htb_parent_to_leaf(q, cl, new_q);
 
        if (--cl->refcnt == 0)
                htb_destroy_class(sch, cl);