diff options
Diffstat (limited to 'drivers/net/ethernet/intel/i40evf/i40e_txrx.c')
| -rw-r--r-- | drivers/net/ethernet/intel/i40evf/i40e_txrx.c | 75 |
1 files changed, 35 insertions, 40 deletions
diff --git a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c index 12b02e530503..c32c62462c84 100644 --- a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c +++ b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c @@ -275,7 +275,7 @@ static bool i40e_clean_tx_irq(struct i40e_vsi *vsi, netdev_tx_completed_queue(txring_txq(tx_ring), total_packets, total_bytes); -#define TX_WAKE_THRESHOLD (DESC_NEEDED * 2) +#define TX_WAKE_THRESHOLD ((s16)(DESC_NEEDED * 2)) if (unlikely(total_packets && netif_carrier_ok(tx_ring->netdev) && (I40E_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD))) { /* Make sure that anybody stopping the queue after this @@ -357,19 +357,31 @@ void i40evf_force_wb(struct i40e_vsi *vsi, struct i40e_q_vector *q_vector) static bool i40e_set_new_dynamic_itr(struct i40e_ring_container *rc) { enum i40e_latency_range new_latency_range = rc->latency_range; - struct i40e_q_vector *qv = rc->ring->q_vector; u32 new_itr = rc->itr; int bytes_per_int; - int usecs; + unsigned int usecs, estimated_usecs; if (rc->total_packets == 0 || !rc->itr) return false; + usecs = (rc->itr << 1) * ITR_COUNTDOWN_START; + bytes_per_int = rc->total_bytes / usecs; + + /* The calculations in this algorithm depend on interrupts actually + * firing at the ITR rate. This may not happen if the packet rate is + * really low, or if we've been napi polling. Check to make sure + * that's not the case before we continue. + */ + estimated_usecs = jiffies_to_usecs(jiffies - rc->last_itr_update); + if (estimated_usecs > usecs) { + new_latency_range = I40E_LOW_LATENCY; + goto reset_latency; + } + /* simple throttlerate management * 0-10MB/s lowest (50000 ints/s) * 10-20MB/s low (20000 ints/s) * 20-1249MB/s bulk (18000 ints/s) - * > 40000 Rx packets per second (8000 ints/s) * * The math works out because the divisor is in 10^(-6) which * turns the bytes/us input value into MB/s values, but @@ -377,9 +389,6 @@ static bool i40e_set_new_dynamic_itr(struct i40e_ring_container *rc) * are in 2 usec increments in the ITR registers, and make sure * to use the smoothed values that the countdown timer gives us. */ - usecs = (rc->itr << 1) * ITR_COUNTDOWN_START; - bytes_per_int = rc->total_bytes / usecs; - switch (new_latency_range) { case I40E_LOWEST_LATENCY: if (bytes_per_int > 10) @@ -392,24 +401,13 @@ static bool i40e_set_new_dynamic_itr(struct i40e_ring_container *rc) new_latency_range = I40E_LOWEST_LATENCY; break; case I40E_BULK_LATENCY: - case I40E_ULTRA_LATENCY: default: if (bytes_per_int <= 20) new_latency_range = I40E_LOW_LATENCY; break; } - /* this is to adjust RX more aggressively when streaming small - * packets. The value of 40000 was picked as it is just beyond - * what the hardware can receive per second if in low latency - * mode. - */ -#define RX_ULTRA_PACKET_RATE 40000 - - if ((((rc->total_packets * 1000000) / usecs) > RX_ULTRA_PACKET_RATE) && - (&qv->rx == rc)) - new_latency_range = I40E_ULTRA_LATENCY; - +reset_latency: rc->latency_range = new_latency_range; switch (new_latency_range) { @@ -422,21 +420,18 @@ static bool i40e_set_new_dynamic_itr(struct i40e_ring_container *rc) case I40E_BULK_LATENCY: new_itr = I40E_ITR_18K; break; - case I40E_ULTRA_LATENCY: - new_itr = I40E_ITR_8K; - break; default: break; } rc->total_bytes = 0; rc->total_packets = 0; + rc->last_itr_update = jiffies; if (new_itr != rc->itr) { rc->itr = new_itr; return true; } - return false; } @@ -1299,7 +1294,7 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget) u16 cleaned_count = I40E_DESC_UNUSED(rx_ring); bool failure = false; - while (likely(total_rx_packets < budget)) { + while (likely(total_rx_packets < (unsigned int)budget)) { struct i40e_rx_buffer *rx_buffer; union i40e_rx_desc *rx_desc; unsigned int size; @@ -1406,7 +1401,7 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget) rx_ring->q_vector->rx.total_bytes += total_rx_bytes; /* guarantee a trip back through this routine if there was a failure */ - return failure ? budget : total_rx_packets; + return failure ? budget : (int)total_rx_packets; } static u32 i40e_buildreg_itr(const int type, const u16 itr) @@ -1575,7 +1570,6 @@ int i40evf_napi_poll(struct napi_struct *napi, int budget) /* If work not completed, return budget and polling will return */ if (!clean_complete) { - const cpumask_t *aff_mask = &q_vector->affinity_mask; int cpu_id = smp_processor_id(); /* It is possible that the interrupt affinity has changed but, @@ -1585,14 +1579,22 @@ int i40evf_napi_poll(struct napi_struct *napi, int budget) * continue to poll, otherwise we must stop polling so the * interrupt can move to the correct cpu. */ - if (likely(cpumask_test_cpu(cpu_id, aff_mask))) { + if (!cpumask_test_cpu(cpu_id, &q_vector->affinity_mask)) { + /* Tell napi that we are done polling */ + napi_complete_done(napi, work_done); + + /* Force an interrupt */ + i40evf_force_wb(vsi, q_vector); + + /* Return budget-1 so that polling stops */ + return budget - 1; + } tx_only: - if (arm_wb) { - q_vector->tx.ring[0].tx_stats.tx_force_wb++; - i40e_enable_wb_on_itr(vsi, q_vector); - } - return budget; + if (arm_wb) { + q_vector->tx.ring[0].tx_stats.tx_force_wb++; + i40e_enable_wb_on_itr(vsi, q_vector); } + return budget; } if (vsi->back->flags & I40E_TXR_FLAGS_WB_ON_ITR) @@ -1601,14 +1603,7 @@ tx_only: /* Work is done so exit the polling mode and re-enable the interrupt */ napi_complete_done(napi, work_done); - /* If we're prematurely stopping polling to fix the interrupt - * affinity we want to make sure polling starts back up so we - * issue a call to i40evf_force_wb which triggers a SW interrupt. - */ - if (!clean_complete) - i40evf_force_wb(vsi, q_vector); - else - i40e_update_enable_itr(vsi, q_vector); + i40e_update_enable_itr(vsi, q_vector); return min(work_done, budget - 1); } |