Re: [PATCH] net: fix problem in dequeuing from input_pkt_queue

[Tom Herbert <therbert@google.com>]

>> It should be okay?  process_backlog only runs in softirq so bottom
>> halves are already disabled, and I don't think flush_backlog runs out
>> of an interrupt.
>>
>
> Oh no. It is an IRQ handler.
>
Very well, I will fix that.

Now I'm wondering, though, what the purpose of flush_backlog is...
since __netif_receive_skb is called with interrupts enabled it's
obvious flush_backlog won't catch all the skb's that reference the
device go away.  Is there a reason these packets need to be flushed
and can't just be processed?

>  on_each_cpu(flush_backlog, dev, 1);
> ...
> int on_each_cpu(void (*func) (void *info), void *info, int wait)
> {
>        int ret = 0;
>
>        preempt_disable();
>        ret = smp_call_function(func, info, wait);
>        local_irq_disable();
>        func(info);
>        local_irq_enable();
>        preempt_enable();
>        return ret;
> }
>
> --
> Regards，
> Changli Gao(xiaosuo@gmail.com)
>