Messages in this thread Patch in this message | | | Date | Tue, 2 Nov 2004 20:18:58 +0100 | From | Ingo Molnar <> | Subject | Re: [patch] Real-Time Preemption, -RT-2.6.9-mm1-V0.6.8 |
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* Mark_H_Johnson@raytheon.com <Mark_H_Johnson@raytheon.com> wrote:
> This build appears to run OK and then in the middle of the real time > tests stops doing useful work (during network test).
weird, the deadlock detector did not trigger, although it is a clear circular deadlock:
R ksoftirqd/0/ 3 [dffe8020, 105] blocked on: [dfcafc20] {r:0,a:-1,&((sk)->sk_lock.slock)} .. held by: rcp/ 4791 [d84bd910, 118] ... acquired at: ip_send_reply+0x12b/0x250
D rcp/ 4791 [d84bd910, 118] blocked on: [c03cb900] {r:0,a:-1,ptype_lock} .. held by: ksoftirqd/0/ 3 [dffe8020, 105] ... acquired at: netif_receive_skb+0xae/0x330
i.e. ksoftirqd blocked on rcp and rcp blocked on ksoftirqd, cleanly deadlocking each other.
anyway, does the patch below, ontop of -V0.6.8, fix this type of hang?
Ingo
--- linux/net/core/dev.c.orig +++ linux/net/core/dev.c @@ -1916,7 +1916,9 @@ static void net_rx_action(struct softirq dev = list_entry(queue->poll_list.next, struct net_device, poll_list); + rcu_read_lock_read(&ptype_lock); if (dev->quota <= 0 || dev->poll(dev, &budget)) { + rcu_read_unlock_read(&ptype_lock); local_irq_disable(); list_del(&dev->poll_list); list_add_tail(&dev->poll_list, &queue->poll_list); @@ -1926,6 +1928,7 @@ static void net_rx_action(struct softirq dev->quota = dev->weight; } else { dev_put(dev); + rcu_read_unlock_read(&ptype_lock); local_irq_disable(); } - 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/
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