diff options
| author | Edward Cree <ecree@solarflare.com> | 2017-01-13 22:20:14 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-01-16 20:00:46 +0100 |
| commit | de1deff994286f464d5cad152d97830a5155f9ba (patch) | |
| tree | e2977c4ce0b4ef87eaa226226b0c52c4ca9de2de /drivers/net/ethernet/sfc/ef10.c | |
| parent | sctp: remove useless code from sctp_apply_peer_addr_params (diff) | |
| download | linux-de1deff994286f464d5cad152d97830a5155f9ba.tar.xz linux-de1deff994286f464d5cad152d97830a5155f9ba.zip | |
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/ef10.c')
| -rw-r--r-- | drivers/net/ethernet/sfc/ef10.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/net/ethernet/sfc/ef10.c b/drivers/net/ethernet/sfc/ef10.c index 208e0048709b..f6e29a975e4e 100644 --- a/drivers/net/ethernet/sfc/ef10.c +++ b/drivers/net/ethernet/sfc/ef10.c @@ -2358,7 +2358,11 @@ static void efx_ef10_tx_write(struct efx_tx_queue *tx_queue) /* Create TX descriptor ring entry */ if (buffer->flags & EFX_TX_BUF_OPTION) { *txd = buffer->option; + if (EFX_QWORD_FIELD(*txd, ESF_DZ_TX_OPTION_TYPE) == 1) + /* PIO descriptor */ + tx_queue->packet_write_count = tx_queue->write_count; } else { + tx_queue->packet_write_count = tx_queue->write_count; BUILD_BUG_ON(EFX_TX_BUF_CONT != 1); EFX_POPULATE_QWORD_3( *txd, @@ -5796,6 +5800,7 @@ const struct efx_nic_type efx_hunt_a0_nic_type = { .rx_ts_offset = ES_DZ_RX_PREFIX_TSTAMP_OFST, .can_rx_scatter = true, .always_rx_scatter = true, + .option_descriptors = true, .max_interrupt_mode = EFX_INT_MODE_MSIX, .timer_period_max = 1 << ERF_DD_EVQ_IND_TIMER_VAL_WIDTH, .offload_features = EF10_OFFLOAD_FEATURES, |