diff options
| author | Ben Hutchings <bhutchings@solarflare.com> | 2009-03-20 13:30:37 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2009-03-21 19:06:58 -0700 |
| commit | 6fb70fd1b57707a5c7b9fb167b7790b2cba13f04 (patch) | |
| tree | 311192bd4de07e1da571f1a6ac6a3ad123ab3f50 /drivers/net/sfc/falcon.c | |
| parent | 85451a951b9511605475fadcc0a8d3aeccefded8 (diff) | |
sfc: Implement adaptive IRQ moderation
Calculate a score for each 1000 IRQs:
- TX completions are worth 1 point
- RX completions are worth 4 if merged using LRO or 2 otherwise
Reduce moderation if the score is less than 10000, down to a minimum
of 5 us. Increase moderation if the score is more than 20000, up to
the specified maximum.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/sfc/falcon.c')
| -rw-r--r-- | drivers/net/sfc/falcon.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/drivers/net/sfc/falcon.c b/drivers/net/sfc/falcon.c index f42fc60d1df..23a1b148d5b 100644 --- a/drivers/net/sfc/falcon.c +++ b/drivers/net/sfc/falcon.c @@ -729,6 +729,9 @@ static void falcon_handle_tx_event(struct efx_channel *channel, tx_ev_desc_ptr = EFX_QWORD_FIELD(*event, TX_EV_DESC_PTR); tx_ev_q_label = EFX_QWORD_FIELD(*event, TX_EV_Q_LABEL); tx_queue = &efx->tx_queue[tx_ev_q_label]; + channel->irq_mod_score += + (tx_ev_desc_ptr - tx_queue->read_count) & + efx->type->txd_ring_mask; efx_xmit_done(tx_queue, tx_ev_desc_ptr); } else if (EFX_QWORD_FIELD(*event, TX_EV_WQ_FF_FULL)) { /* Rewrite the FIFO write pointer */ @@ -898,6 +901,8 @@ static void falcon_handle_rx_event(struct efx_channel *channel, discard = true; } + channel->irq_mod_score += 2; + /* Handle received packet */ efx_rx_packet(rx_queue, rx_ev_desc_ptr, rx_ev_byte_cnt, checksummed, discard); @@ -1075,14 +1080,15 @@ void falcon_set_int_moderation(struct efx_channel *channel) * program is based at 0. So actual interrupt moderation * achieved is ((x + 1) * res). */ - unsigned int res = 5; - channel->irq_moderation -= (channel->irq_moderation % res); - if (channel->irq_moderation < res) - channel->irq_moderation = res; + channel->irq_moderation -= (channel->irq_moderation % + FALCON_IRQ_MOD_RESOLUTION); + if (channel->irq_moderation < FALCON_IRQ_MOD_RESOLUTION) + channel->irq_moderation = FALCON_IRQ_MOD_RESOLUTION; EFX_POPULATE_DWORD_2(timer_cmd, TIMER_MODE, TIMER_MODE_INT_HLDOFF, TIMER_VAL, - (channel->irq_moderation / res) - 1); + channel->irq_moderation / + FALCON_IRQ_MOD_RESOLUTION - 1); } else { EFX_POPULATE_DWORD_2(timer_cmd, TIMER_MODE, TIMER_MODE_DIS, |