igb: Don't receive packets when the napi budget == 0

Processing any incoming packets with a with a napi budget of 0
is incorrect driver behavior.

This matters as netpoll will shortly call drivers with a budget of 0
to avoid receive packet processing happening in hard irq context.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c
index f81d87c..d6b1152 100644 (file)
--- a/drivers/net/ethernet/intel/igb/igb_main.c
+++ b/drivers/net/ethernet/intel/igb/igb_main.c
@@ -6946,7 +6946,7 @@ static bool igb_clean_rx_irq(struct igb_q_vector *q_vector, const int budget)
        unsigned int total_bytes = 0, total_packets = 0;
        u16 cleaned_count = igb_desc_unused(rx_ring);
 
-       do {
+       while (likely(total_packets < budget)) {
                union e1000_adv_rx_desc *rx_desc;
 
                /* return some buffers to hardware, one at a time is too slow */
@@ -6998,7 +6998,7 @@ static bool igb_clean_rx_irq(struct igb_q_vector *q_vector, const int budget)
 
                /* update budget accounting */
                total_packets++;
-       } while (likely(total_packets < budget));
+       }
 
        /* place incomplete frames back on ring for completion */
        rx_ring->skb = skb;