2005-11-14 Paul Jakma <paul.jakma@sun.com>
* (general) Add state to detect queue floods. There's no sense
trying to be sparing of CPU resources, if the queue is
flooding and using ever more memory resources. we should just
get on with clearing the queue.
The sense of delay and hold were wrong way around, fix.
* workqueue.h: (struct work_queue) Add status bitfield. Add
'flood' integer to workqueue spec. Add runs_since_clear
counter to workqueue.
* workqueue.c: (work_queue_new) set defaults for delay, hold
and flood.
(work_queue_add) initial schedule should use delay, not hold.
(show_work_queues) Print flood field, conserve whitespace.
(work_queue_unplug) use delay, not hold.
(work_queue_run) consecutive runs should be seperated by hold
time, not delay.
Keep track of number of consecutive runs, go into 'overdrive'
if queue is being flooded, we can't avoid making heavy use of
resources, better to use CPU than ever more RAM.
diff --git a/lib/workqueue.c b/lib/workqueue.c
index bac4130..c2ff10d 100644
--- a/lib/workqueue.c
+++ b/lib/workqueue.c
@@ -80,7 +80,12 @@
listnode_add (&work_queues, new);
new->cycles.granularity = WORK_QUEUE_MIN_GRANULARITY;
-
+
+ /* Default values, can be overriden by caller */
+ new->spec.delay = WORK_QUEUE_DEFAULT_DELAY;
+ new->spec.hold = WORK_QUEUE_DEFAULT_HOLD;
+ new->spec.flood = WORK_QUEUE_DEFAULT_FLOOD;
+
return new;
}
@@ -128,7 +133,7 @@
item->data = data;
listnode_add (wq->items, item);
- work_queue_schedule (wq, wq->spec.hold);
+ work_queue_schedule (wq, wq->spec.delay);
return;
}
@@ -167,12 +172,12 @@
struct work_queue *wq;
vty_out (vty,
- "%c %8s %11s %8s %21s%s",
- ' ', "List","(ms) ","Q. Runs","Cycle Counts ",
+ "%c%c %8s %11s %8s %21s%s",
+ ' ', ' ', "List","(ms) ","Q. Runs","Cycle Counts ",
VTY_NEWLINE);
vty_out (vty,
- "%c %8s %5s %5s %8s %7s %6s %6s %s%s",
- ' ',
+ "%c%c %8s %5s %5s %8s %7s %6s %6s %s%s",
+ 'P', 'F',
"Items",
"Delay","Hold",
"Total",
@@ -182,8 +187,9 @@
for (ALL_LIST_ELEMENTS_RO ((&work_queues), node, wq))
{
- vty_out (vty,"%c %8d %5d %5d %8ld %7d %6d %6u %s%s",
+ vty_out (vty,"%c%c %8d %5d %5d %8ld %7d %6d %6u %s%s",
(wq->flags == WQ_PLUGGED ? 'P' : ' '),
+ (wq->runs_since_clear >= wq->spec.flood ? 'F' : ' '),
listcount (wq->items),
wq->spec.delay, wq->spec.hold,
wq->runs,
@@ -220,7 +226,7 @@
wq->flags = WQ_UNPLUGGED;
/* if thread isnt already waiting, add one */
- work_queue_schedule (wq, wq->spec.hold);
+ work_queue_schedule (wq, wq->spec.delay);
}
/* timer thread to process a work queue
@@ -364,9 +370,19 @@
/* Is the queue done yet? If it is, call the completion callback. */
if (listcount (wq->items) > 0)
- work_queue_schedule (wq, wq->spec.delay);
- else if (wq->spec.completion_func)
- wq->spec.completion_func (wq);
+ {
+ if (++(wq->runs_since_clear) < wq->spec.flood)
+ work_queue_schedule (wq, wq->spec.hold);
+ else
+ work_queue_schedule (wq, 0); /* queue flooded, go into overdrive */
+ }
+ else
+ {
+ wq->runs_since_clear = 0;
+
+ if (wq->spec.completion_func)
+ wq->spec.completion_func (wq);
+ }
return 0;
}