Messages in this thread | | | Date | Sat, 20 Jan 2007 15:54:00 +0530 | From | "kalash nainwal" <> | Subject | wake_up() takes long time to return |
| |
Hi there,
We've a kernel (n/w) module, which sits over ethernet. Whenever a pkt is received (in softirq), after doing some minimal processing, wake_up() is called to wake up another kernel thread which does rest (bulk) of the processing.
We notice that this wake_up() call is sometimes taking as long as 48 milli-seconds to return. This happens around 10 times out of 10M. We earlier thought its possibly because of the contention on rq->lock, but we see the same phenomenon even on a uniprocessor box. So obviosly thats not the case.
We can't figure out any other reason for wake_up() to take this much time? As this call comes directly in our (receive) hotpath, we're very concerned. Any help would be greatly appreciated.
Thanks and regards, -Kalash - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |