sfc: Break NAPI processing after one ring-full of TX completions

Currently TX completions do not count towards the NAPI budget.  This
means a continuous stream of TX completions can cause the polling
function to loop indefinitely with scheduling disabled.  To avoid
this, follow the common practice of reporting the budget spent after
processing one ring-full of TX completions.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 9 insertions, 9 deletions

diff --git a/drivers/net/sfc/efx.c b/drivers/net/sfc/efx.c
index 1ad61b7bba40..5e3f944fdd95 100644
--- a/drivers/net/sfc/efx.c
+++ b/drivers/net/sfc/efx.c
@@ -225,17 +225,17 @@ static void efx_fini_channels(struct efx_nic *efx);
  * never be concurrently called more than once on the same channel,
  * though different channels may be being processed concurrently.
  */
-static int efx_process_channel(struct efx_channel *channel, int rx_quota)
+static int efx_process_channel(struct efx_channel *channel, int budget)
 {
         struct efx_nic *efx = channel->efx;
-        int rx_packets;
+        int spent;
 
         if (unlikely(efx->reset_pending != RESET_TYPE_NONE ||
                      !channel->enabled))
                 return 0;
 
-        rx_packets = efx_nic_process_eventq(channel, rx_quota);
-        if (rx_packets == 0)
+        spent = efx_nic_process_eventq(channel, budget);
+        if (spent == 0)
                 return 0;
 
         /* Deliver last RX packet. */
@@ -249,7 +249,7 @@ static int efx_process_channel(struct efx_channel *channel, int rx_quota)
 
         efx_fast_push_rx_descriptors(&efx->rx_queue[channel->channel]);
 
-        return rx_packets;
+        return spent;
 }
 
 /* Mark channel as finished processing
@@ -278,14 +278,14 @@ static int efx_poll(struct napi_struct *napi, int budget)
 {
         struct efx_channel *channel =
                 container_of(napi, struct efx_channel, napi_str);
-        int rx_packets;
+        int spent;
 
         EFX_TRACE(channel->efx, "channel %d NAPI poll executing on CPU %d\n",
                   channel->channel, raw_smp_processor_id());
 
-        rx_packets = efx_process_channel(channel, budget);
+        spent = efx_process_channel(channel, budget);
 
-        if (rx_packets < budget) {
+        if (spent < budget) {
                 struct efx_nic *efx = channel->efx;
 
                 if (channel->used_flags & EFX_USED_BY_RX &&
@@ -318,7 +318,7 @@ static int efx_poll(struct napi_struct *napi, int budget)
                 efx_channel_processed(channel);
         }
 
-        return rx_packets;
+        return spent;
 }
 
 /* Process the eventq of the specified channel immediately on this CPU