Re: BNX driver problem when mbuf clusters run out

[Beverly Schwartz <bschwart%bbn.com@localhost>]

On Apr 20, 2012, at 1:27 AM, Matt Thomas wrote:

> 
> On Apr 19, 2012, at 6:48 PM, Beverly Schwartz wrote:
> 
>> 
>> On Apr 19, 2012, at 8:27 PM, Matt Thomas wrote:
>> 
>>> 
>>> On Apr 19, 2012, at 5:08 PM, Beverly Schwartz wrote:
>>> 
>>>> 
>>>> On Apr 19, 2012, at 8:02 PM, Matt Thomas wrote:
>>>>> 
>>>>> Unfortunately, that can lead to receiver livelock (spend all the time 
>>>>> servicing interrupts without making progress).  The best thing to do is 
>>>>> pass the packet up the stack and just another packet to the hardware.  
>>>>> Instead use bnx_tick to add mbufs if needed.  This gives the stack a 
>>>>> chance to run and hopefully free some mbufs.
>>>> 
>>>> I tried that.  And at first, things move along.  But eventually, 
>>>> bnx_rx_intr never gets called, because 
>>>> if (sblk->status_rx_quick_consumer_index0 != sc->nw_rx_cons)
>>>> in bnx_intr always fails.
>>> 
>>> For now, can you try the patch at
>>> 
>>> http://www.netbsd.org/~matt/if_bnx-diff.txt
>>> 
>>> It's kind of ugly but it is a minimal change.
>> 
>> Doesn't quite do it.  With this change, the sw_cons index doesn't get 
>> incremented.  Next time bnx_rx_intr is called, we'll have the same overwrite 
>> problem.  I'm now trying incremeing sw_cons before calling break.  When I 
>> left work, it was still running.  Tomorrow morning, I'll see if everything 
>> is still intact.
> 
> It should get incremented since 
> 
>       sw_cons = NEXT_RX_BD(sw_cons);
> 
> is after the loop.

It's after the if conditional.  It's still in the loop.

-Bev