kern/155030: [igb] igb(4) DEVICE_POLLING does not work with carp(4)

[Mark Johnston]

The following reply was made to PR kern/155030; it has been noted by GNATS.

From: Mark Johnston <markjdb at gmail.com>
To: bug-followup at FreeBSD.org, mm at FreeBSD.org
Cc:  
Subject: Re: kern/155030: [igb] igb(4) DEVICE_POLLING does not work with
 carp(4)
Date: Thu, 21 Jun 2012 21:38:36 -0400

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 Another way to go is just to fix igb(4)'s polling routine to work with
 multiple queues. That's what I've done in the src tree at my work; the
 patch is attached.
 
 Can you test it and let me know if it solves your problem? If so, I'll
 bug jfv@ to commit it. =)
 
 Thanks,
 -Mark
 
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 Content-Disposition: attachment; filename="igb_polling.patch"
 
 diff --git a/share/man/man4/polling.4 b/share/man/man4/polling.4
 index 2c711cc..6abc37c 100644
 --- a/share/man/man4/polling.4
 +++ b/share/man/man4/polling.4
 @@ -184,6 +184,7 @@ As of this writing, the
  .Xr fwe 4 ,
  .Xr fwip 4 ,
  .Xr fxp 4 ,
 +.Xr igb 4 ,
  .Xr ixgb 4 ,
  .Xr nfe 4 ,
  .Xr nge 4 ,
 diff --git a/sys/dev/e1000/if_igb.c b/sys/dev/e1000/if_igb.c
 index cb6c63f..7a92b9a 100644
 --- a/sys/dev/e1000/if_igb.c
 +++ b/sys/dev/e1000/if_igb.c
 @@ -1482,12 +1482,6 @@ igb_irq_fast(void *arg)
  }
  
  #ifdef DEVICE_POLLING
 -/*********************************************************************
 - *
 - *  Legacy polling routine : if using this code you MUST be sure that
 - *  multiqueue is not defined, ie, set igb_num_queues to 1.
 - *
 - *********************************************************************/
  #if __FreeBSD_version >= 800000
  #define POLL_RETURN_COUNT(a) (a)
  static int
 @@ -1498,11 +1492,12 @@ static void
  igb_poll(struct ifnet *ifp, enum poll_cmd cmd, int count)
  {
  	struct adapter		*adapter = ifp->if_softc;
 -	struct igb_queue	*que = adapter->queues;
 -	struct tx_ring		*txr = adapter->tx_rings;
 +	struct igb_queue	*que;
 +	struct tx_ring		*txr;
  	u32			reg_icr, rx_done = 0;
  	u32			loop = IGB_MAX_LOOP;
  	bool			more;
 +	int			i;
  
  	IGB_CORE_LOCK(adapter);
  	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
 @@ -1521,20 +1516,26 @@ igb_poll(struct ifnet *ifp, enum poll_cmd cmd, int count)
  	}
  	IGB_CORE_UNLOCK(adapter);
  
 -	igb_rxeof(que, count, &rx_done);
 +	for (i = 0; i < adapter->num_queues; i++) {
 +		que = &adapter->queues[i];
 +		txr = que->txr;
 +
 +		igb_rxeof(que, count, &rx_done);
  
 -	IGB_TX_LOCK(txr);
 -	do {
 -		more = igb_txeof(txr);
 -	} while (loop-- && more);
 +		IGB_TX_LOCK(txr);
 +		do {
 +			more = igb_txeof(txr);
 +		} while (loop-- && more);
  #if __FreeBSD_version >= 800000
 -	if (!drbr_empty(ifp, txr->br))
 -		igb_mq_start_locked(ifp, txr, NULL);
 +		if (!drbr_empty(ifp, txr->br))
 +			igb_mq_start_locked(ifp, txr, NULL);
  #else
 -	if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
 -		igb_start_locked(txr, ifp);
 +		if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
 +			igb_start_locked(txr, ifp);
  #endif
 -	IGB_TX_UNLOCK(txr);
 +		IGB_TX_UNLOCK(txr);
 +	}
 +
  	return POLL_RETURN_COUNT(rx_done);
  }
  #endif /* DEVICE_POLLING */
 @@ -4846,7 +4847,7 @@ next_desc:
  	}
  
  	if (done != NULL)
 -		*done = rxdone;
 +		*done += rxdone;
  
  	IGB_RX_UNLOCK(rxr);
  	return ((staterr & E1000_RXD_STAT_DD) ? TRUE : FALSE);
 
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