if (total_tx_packets >= tx_ring->work_limit)
IXGBE_WRITE_REG(&adapter->hw, IXGBE_EICS, tx_ring->eims_value);
+ tx_ring->total_bytes += total_tx_bytes;
+ tx_ring->total_packets += total_tx_packets;
adapter->net_stats.tx_bytes += total_tx_bytes;
adapter->net_stats.tx_packets += total_tx_packets;
cleaned = total_tx_packets ? true : false;
adapter->net_stats.rx_bytes += total_rx_bytes;
adapter->net_stats.rx_packets += total_rx_packets;
+ rx_ring->total_packets += total_rx_packets;
+ rx_ring->total_bytes += total_rx_bytes;
+ adapter->net_stats.rx_bytes += total_rx_bytes;
+ adapter->net_stats.rx_packets += total_rx_packets;
+
return cleaned;
}
IXGBE_WRITE_REG(&adapter->hw, IXGBE_EIAC, mask);
}
+enum latency_range {
+ lowest_latency = 0,
+ low_latency = 1,
+ bulk_latency = 2,
+ latency_invalid = 255
+};
+
+/**
+ * ixgbe_update_itr - update the dynamic ITR value based on statistics
+ * @adapter: pointer to adapter
+ * @eitr: eitr setting (ints per sec) to give last timeslice
+ * @itr_setting: current throttle rate in ints/second
+ * @packets: the number of packets during this measurement interval
+ * @bytes: the number of bytes during this measurement interval
+ *
+ * Stores a new ITR value based on packets and byte
+ * counts during the last interrupt. The advantage of per interrupt
+ * computation is faster updates and more accurate ITR for the current
+ * traffic pattern. Constants in this function were computed
+ * based on theoretical maximum wire speed and thresholds were set based
+ * on testing data as well as attempting to minimize response time
+ * while increasing bulk throughput.
+ * this functionality is controlled by the InterruptThrottleRate module
+ * parameter (see ixgbe_param.c)
+ **/
+static u8 ixgbe_update_itr(struct ixgbe_adapter *adapter,
+ u32 eitr, u8 itr_setting,
+ int packets, int bytes)
+{
+ unsigned int retval = itr_setting;
+ u32 timepassed_us;
+ u64 bytes_perint;
+
+ if (packets == 0)
+ goto update_itr_done;
+
+
+ /* simple throttlerate management
+ * 0-20MB/s lowest (100000 ints/s)
+ * 20-100MB/s low (20000 ints/s)
+ * 100-1249MB/s bulk (8000 ints/s)
+ */
+ /* what was last interrupt timeslice? */
+ timepassed_us = 1000000/eitr;
+ bytes_perint = bytes / timepassed_us; /* bytes/usec */
+
+ switch (itr_setting) {
+ case lowest_latency:
+ if (bytes_perint > adapter->eitr_low)
+ retval = low_latency;
+ break;
+ case low_latency:
+ if (bytes_perint > adapter->eitr_high)
+ retval = bulk_latency;
+ else if (bytes_perint <= adapter->eitr_low)
+ retval = lowest_latency;
+ break;
+ case bulk_latency:
+ if (bytes_perint <= adapter->eitr_high)
+ retval = low_latency;
+ break;
+ }
+
+update_itr_done:
+ return retval;
+}
+
+static void ixgbe_set_itr_msix(struct ixgbe_q_vector *q_vector)
+{
+ struct ixgbe_adapter *adapter = q_vector->adapter;
+ struct ixgbe_hw *hw = &adapter->hw;
+ u32 new_itr;
+ u8 current_itr, ret_itr;
+ int i, r_idx, v_idx = ((void *)q_vector - (void *)(adapter->q_vector)) /
+ sizeof(struct ixgbe_q_vector);
+ struct ixgbe_ring *rx_ring, *tx_ring;
+
+ r_idx = find_first_bit(q_vector->txr_idx, adapter->num_tx_queues);
+ for (i = 0; i < q_vector->txr_count; i++) {
+ tx_ring = &(adapter->tx_ring[r_idx]);
+ ret_itr = ixgbe_update_itr(adapter, q_vector->eitr,
+ q_vector->tx_eitr,
+ tx_ring->total_packets,
+ tx_ring->total_bytes);
+ /* if the result for this queue would decrease interrupt
+ * rate for this vector then use that result */
+ q_vector->tx_eitr = ((q_vector->tx_eitr > ret_itr) ?
+ q_vector->tx_eitr - 1 : ret_itr);
+ r_idx = find_next_bit(q_vector->txr_idx, adapter->num_tx_queues,
+ r_idx + 1);
+ }
+
+ r_idx = find_first_bit(q_vector->rxr_idx, adapter->num_rx_queues);
+ for (i = 0; i < q_vector->rxr_count; i++) {
+ rx_ring = &(adapter->rx_ring[r_idx]);
+ ret_itr = ixgbe_update_itr(adapter, q_vector->eitr,
+ q_vector->rx_eitr,
+ rx_ring->total_packets,
+ rx_ring->total_bytes);
+ /* if the result for this queue would decrease interrupt
+ * rate for this vector then use that result */
+ q_vector->rx_eitr = ((q_vector->rx_eitr > ret_itr) ?
+ q_vector->rx_eitr - 1 : ret_itr);
+ r_idx = find_next_bit(q_vector->rxr_idx, adapter->num_rx_queues,
+ r_idx + 1);
+ }
+
+ current_itr = max(q_vector->rx_eitr, q_vector->tx_eitr);
+
+ switch (current_itr) {
+ /* counts and packets in update_itr are dependent on these numbers */
+ case lowest_latency:
+ new_itr = 100000;
+ break;
+ case low_latency:
+ new_itr = 20000; /* aka hwitr = ~200 */
+ break;
+ case bulk_latency:
+ default:
+ new_itr = 8000;
+ break;
+ }
+
+ if (new_itr != q_vector->eitr) {
+ u32 itr_reg;
+ /* do an exponential smoothing */
+ new_itr = ((q_vector->eitr * 90)/100) + ((new_itr * 10)/100);
+ q_vector->eitr = new_itr;
+ itr_reg = EITR_INTS_PER_SEC_TO_REG(new_itr);
+ /* must write high and low 16 bits to reset counter */
+ DPRINTK(TX_ERR, DEBUG, "writing eitr(%d): %08X\n", v_idx,
+ itr_reg);
+ IXGBE_WRITE_REG(hw, IXGBE_EITR(v_idx), itr_reg | (itr_reg)<<16);
+ }
+
+ return;
+}
+
static irqreturn_t ixgbe_msix_lsc(int irq, void *data)
{
struct net_device *netdev = data;
r_idx = find_first_bit(q_vector->txr_idx, adapter->num_tx_queues);
for (i = 0; i < q_vector->txr_count; i++) {
txr = &(adapter->tx_ring[r_idx]);
+ txr->total_bytes = 0;
+ txr->total_packets = 0;
ixgbe_clean_tx_irq(adapter, txr);
r_idx = find_next_bit(q_vector->txr_idx, adapter->num_tx_queues,
r_idx + 1);
}
-
return IRQ_HANDLED;
}
rxr = &(adapter->rx_ring[r_idx]);
/* disable interrupts on this vector only */
IXGBE_WRITE_REG(&adapter->hw, IXGBE_EIMC, rxr->v_idx);
+ rxr->total_bytes = 0;
+ rxr->total_packets = 0;
netif_rx_schedule(adapter->netdev, &q_vector->napi);
return IRQ_HANDLED;
/* If all Rx work done, exit the polling mode */
if (work_done < budget) {
netif_rx_complete(adapter->netdev, napi);
+ if (adapter->rx_eitr < IXGBE_MIN_ITR_USECS)
+ ixgbe_set_itr_msix(q_vector);
if (!test_bit(__IXGBE_DOWN, &adapter->state))
IXGBE_WRITE_REG(&adapter->hw, IXGBE_EIMS, rxr->v_idx);
}
return err;
}
+static void ixgbe_set_itr(struct ixgbe_adapter *adapter)
+{
+ struct ixgbe_hw *hw = &adapter->hw;
+ struct ixgbe_q_vector *q_vector = adapter->q_vector;
+ u8 current_itr;
+ u32 new_itr = q_vector->eitr;
+ struct ixgbe_ring *rx_ring = &adapter->rx_ring[0];
+ struct ixgbe_ring *tx_ring = &adapter->tx_ring[0];
+
+ q_vector->tx_eitr = ixgbe_update_itr(adapter, new_itr,
+ q_vector->tx_eitr,
+ tx_ring->total_packets,
+ tx_ring->total_bytes);
+ q_vector->rx_eitr = ixgbe_update_itr(adapter, new_itr,
+ q_vector->rx_eitr,
+ rx_ring->total_packets,
+ rx_ring->total_bytes);
+
+ current_itr = max(q_vector->rx_eitr, q_vector->tx_eitr);
+
+ switch (current_itr) {
+ /* counts and packets in update_itr are dependent on these numbers */
+ case lowest_latency:
+ new_itr = 100000;
+ break;
+ case low_latency:
+ new_itr = 20000; /* aka hwitr = ~200 */
+ break;
+ case bulk_latency:
+ new_itr = 8000;
+ break;
+ default:
+ break;
+ }
+
+ if (new_itr != q_vector->eitr) {
+ u32 itr_reg;
+ /* do an exponential smoothing */
+ new_itr = ((q_vector->eitr * 90)/100) + ((new_itr * 10)/100);
+ q_vector->eitr = new_itr;
+ itr_reg = EITR_INTS_PER_SEC_TO_REG(new_itr);
+ /* must write high and low 16 bits to reset counter */
+ IXGBE_WRITE_REG(hw, IXGBE_EITR(0), itr_reg | (itr_reg)<<16);
+ }
+
+ return;
+}
+
static inline void ixgbe_irq_enable(struct ixgbe_adapter *adapter);
/**
if (netif_rx_schedule_prep(netdev, &adapter->q_vector[0].napi)) {
+ adapter->tx_ring[0].total_packets = 0;
+ adapter->tx_ring[0].total_bytes = 0;
+ adapter->rx_ring[0].total_packets = 0;
+ adapter->rx_ring[0].total_bytes = 0;
/* would disable interrupts here but EIAM disabled it */
__netif_rx_schedule(netdev, &adapter->q_vector[0].napi);
}
}
}
-
static void ixgbe_configure(struct ixgbe_adapter *adapter)
{
struct net_device *netdev = adapter->netdev;
/* If budget not fully consumed, exit the polling mode */
if (work_done < budget) {
netif_rx_complete(adapter->netdev, napi);
+ if (adapter->rx_eitr < IXGBE_MIN_ITR_USECS)
+ ixgbe_set_itr(adapter);
if (!test_bit(__IXGBE_DOWN, &adapter->state))
ixgbe_irq_enable(adapter);
}
adapter->ring_feature[RING_F_RSS].indices = rss;
adapter->flags |= IXGBE_FLAG_RSS_ENABLED;
+ /* Enable Dynamic interrupt throttling by default */
+ adapter->rx_eitr = 1;
+ adapter->tx_eitr = 1;
+
/* default flow control settings */
hw->fc.original_type = ixgbe_fc_full;
hw->fc.type = ixgbe_fc_full;
projects / linux-2.6 / commitdiff