path: root/drivers/net/ethernet/sfc/tx.c
diff options
authorEdward Cree <ecree@solarflare.com>2017-01-13 21:20:14 +0000
committerDavid S. Miller <davem@davemloft.net>2017-01-16 14:00:46 -0500
commitde1deff994286f464d5cad152d97830a5155f9ba (patch)
treee2977c4ce0b4ef87eaa226226b0c52c4ca9de2de /drivers/net/ethernet/sfc/tx.c
parentsctp: remove useless code from sctp_apply_peer_addr_params (diff)
sfc: allow PIO more often
If an option descriptor has been sent on a queue but not followed by a packet, there will have been no completion event, so the read and write counts won't match and we'll think we can't do PIO. This combines with the fact that we have two TX queues (for en/disable checksum offload), and that both must be empty for PIO to happen. This patch adds a separate "packet_write_count" that tracks the most recent write_count we expect to see a completion event for; this excludes option descriptors but _includes_ PIO descriptors (even though they look like option descriptors). This is then used, rather than write_count, in efx_nic_tx_is_empty(). We only bother to maintain packet_write_count on EF10, since on Siena (a) there are no option descriptors and it always equals write_count, and (b) there's no PIO, so we don't need it anyway. Signed-off-by: Edward Cree <ecree@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/sfc/tx.c')
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/net/ethernet/sfc/tx.c b/drivers/net/ethernet/sfc/tx.c
index 3c0151424d12..beaf98080a0b 100644
--- a/drivers/net/ethernet/sfc/tx.c
+++ b/drivers/net/ethernet/sfc/tx.c
@@ -817,6 +817,7 @@ void efx_init_tx_queue(struct efx_tx_queue *tx_queue)
tx_queue->insert_count = 0;
tx_queue->write_count = 0;
+ tx_queue->packet_write_count = 0;
tx_queue->old_write_count = 0;
tx_queue->read_count = 0;
tx_queue->old_read_count = 0;