Re: NMI lockup, 2.6.26 release

[Jarek Poplawski <jarkao2@gmail.com>]

Hi Denys,

In case this is still working after hrtimer -> timer change here is
another patch for testing: to check if limiting hrtimers scheduling
could matter here. Btw. could you write what is the approximate
number of htb qdiscs and classes working on each device of this box
(including ifbs)?

Thanks,
Jarek P.

(This patch should be applided to 2.6.26 or .25 after reverting
the previous debugging patch.)

---

 net/sched/sch_htb.c |    8 +++++++-
 1 files changed, 7 insertions(+), 1 deletions(-)

diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c
index 30c999c..ff9e965 100644
--- a/net/sched/sch_htb.c
+++ b/net/sched/sch_htb.c
@@ -162,6 +162,7 @@ struct htb_sched {
 
 	int rate2quantum;	/* quant = rate / rate2quantum */
 	psched_time_t now;	/* cached dequeue time */
+	psched_time_t next_watchdog;
 	struct qdisc_watchdog watchdog;
 
 	/* non shaped skbs; let them go directly thru */
@@ -920,7 +921,11 @@ static struct sk_buff *htb_dequeue(struct Qdisc *sch)
 		}
 	}
 	sch->qstats.overlimits++;
-	qdisc_watchdog_schedule(&q->watchdog, next_event);
+	if (q->next_watchdog < q->now || next_event <=
+	     q->next_watchdog - PSCHED_TICKS_PER_SEC / HZ) {
+		qdisc_watchdog_schedule(&q->watchdog, next_event);
+		q->next_watchdog = next_event;
+	}
 fin:
 	return skb;
 }
@@ -973,6 +978,7 @@ static void htb_reset(struct Qdisc *sch)
 		}
 	}
 	qdisc_watchdog_cancel(&q->watchdog);
+	q->next_watchdog = 0;
 	__skb_queue_purge(&q->direct_queue);
 	sch->q.qlen = 0;
 	memset(q->row, 0, sizeof(q->row));