ixgbe: bulk free SKBs during TX completion cleanup cycle

There is an opportunity to bulk free SKBs during reclaiming of
resources after DMA transmit completes in ixgbe_clean_tx_irq.  Thus,
bulk freeing at this point does not introduce any added latency.

Simply use napi_consume_skb() which were recently introduced.  The
napi_budget parameter is needed by napi_consume_skb() to detect if it
is called from netpoll.

Benchmarking IPv4-forwarding, on CPU i7-4790K @4.2GHz (no turbo boost)
 Single CPU/flow numbers: before: 1982144 pps ->  after : 2064446 pps
 Improvement: +82302 pps, -20 nanosec, +4.1%
 (SLUB and GCC version 5.1.1 20150618 (Red Hat 5.1.1-4))

Joint work with Alexander Duyck.

Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jesper Dangaard Brouer 2016-02-08 13:15:09 +01:00 committed by David S. Miller
parent 15fad714be
commit a3a8749d34

View File

@ -1089,7 +1089,7 @@ static void ixgbe_tx_timeout_reset(struct ixgbe_adapter *adapter)
* @tx_ring: tx ring to clean
**/
static bool ixgbe_clean_tx_irq(struct ixgbe_q_vector *q_vector,
struct ixgbe_ring *tx_ring)
struct ixgbe_ring *tx_ring, int napi_budget)
{
struct ixgbe_adapter *adapter = q_vector->adapter;
struct ixgbe_tx_buffer *tx_buffer;
@ -1127,7 +1127,7 @@ static bool ixgbe_clean_tx_irq(struct ixgbe_q_vector *q_vector,
total_packets += tx_buffer->gso_segs;
/* free the skb */
dev_consume_skb_any(tx_buffer->skb);
napi_consume_skb(tx_buffer->skb, napi_budget);
/* unmap skb header data */
dma_unmap_single(tx_ring->dev,
@ -2784,7 +2784,7 @@ int ixgbe_poll(struct napi_struct *napi, int budget)
#endif
ixgbe_for_each_ring(ring, q_vector->tx)
clean_complete &= !!ixgbe_clean_tx_irq(q_vector, ring);
clean_complete &= !!ixgbe_clean_tx_irq(q_vector, ring, budget);
/* Exit if we are called by netpoll or busy polling is active */
if ((budget <= 0) || !ixgbe_qv_lock_napi(q_vector))