ionic: separate interrupt for Tx and Rx

Add the capability to split the Tx queues onto their own
interrupts with their own napi contexts.  This gives the
opportunity for more direct control of Tx interrupt
handling, such as CPU affinity and interrupt coalescing,
useful for some traffic loads.

v2: use ethtool -L, not a vendor specific priv-flag
v3: simplify logging, drop unnecessary "no-change" tests

Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/pensando/ionic/ionic_ethtool.c b/drivers/net/ethernet/pensando/ionic/ionic_ethtool.c
index 095561924bdc13a3039edb5b42501da40a297743..3c57c331729f2a8a53957faaa2e52c4db90ead31 100644 (file)
--- a/drivers/net/ethernet/pensando/ionic/ionic_ethtool.c
+++ b/drivers/net/ethernet/pensando/ionic/ionic_ethtool.c
@@ -403,8 +403,7 @@ static int ionic_get_coalesce(struct net_device *netdev,
 {
        struct ionic_lif *lif = netdev_priv(netdev);
 
-       /* Tx uses Rx interrupt */
-       coalesce->tx_coalesce_usecs = lif->rx_coalesce_usecs;
+       coalesce->tx_coalesce_usecs = lif->tx_coalesce_usecs;
        coalesce->rx_coalesce_usecs = lif->rx_coalesce_usecs;
 
        return 0;
@@ -417,7 +416,8 @@ static int ionic_set_coalesce(struct net_device *netdev,
        struct ionic_identity *ident;
        struct ionic_qcq *qcq;
        unsigned int i;
-       u32 coal;
+       u32 rx_coal;
+       u32 tx_coal;
 
        ident = &lif->ionic->ident;
        if (ident->dev.intr_coal_div == 0) {
@@ -426,26 +426,31 @@ static int ionic_set_coalesce(struct net_device *netdev,
                return -EIO;
        }
 
-       /* Tx uses Rx interrupt, so only change Rx */
-       if (coalesce->tx_coalesce_usecs != lif->rx_coalesce_usecs) {
+       /* Tx normally shares Rx interrupt, so only change Rx */
+       if (!test_bit(IONIC_LIF_F_SPLIT_INTR, lif->state) &&
+           coalesce->tx_coalesce_usecs != lif->rx_coalesce_usecs) {
                netdev_warn(netdev, "only the rx-usecs can be changed\n");
                return -EINVAL;
        }
 
-       /* Convert the usec request to a HW useable value.  If they asked
+       /* Convert the usec request to a HW usable value.  If they asked
         * for non-zero and it resolved to zero, bump it up
         */
-       coal = ionic_coal_usec_to_hw(lif->ionic, coalesce->rx_coalesce_usecs);
-       if (!coal && coalesce->rx_coalesce_usecs)
-               coal = 1;
-
-       if (coal > IONIC_INTR_CTRL_COAL_MAX)
+       rx_coal = ionic_coal_usec_to_hw(lif->ionic, coalesce->rx_coalesce_usecs);
+       if (!rx_coal && coalesce->rx_coalesce_usecs)
+               rx_coal = 1;
+       tx_coal = ionic_coal_usec_to_hw(lif->ionic, coalesce->tx_coalesce_usecs);
+       if (!tx_coal && coalesce->tx_coalesce_usecs)
+               tx_coal = 1;
+
+       if (rx_coal > IONIC_INTR_CTRL_COAL_MAX ||
+           tx_coal > IONIC_INTR_CTRL_COAL_MAX)
                return -ERANGE;
 
-       /* Save the new value */
+       /* Save the new values */
        lif->rx_coalesce_usecs = coalesce->rx_coalesce_usecs;
-       if (coal != lif->rx_coalesce_hw) {
-               lif->rx_coalesce_hw = coal;
+       if (rx_coal != lif->rx_coalesce_hw) {
+               lif->rx_coalesce_hw = rx_coal;
 
                if (test_bit(IONIC_LIF_F_UP, lif->state)) {
                        for (i = 0; i < lif->nxqs; i++) {
@@ -457,6 +462,23 @@ static int ionic_set_coalesce(struct net_device *netdev,
                }
        }
 
+       if (test_bit(IONIC_LIF_F_SPLIT_INTR, lif->state))
+               lif->tx_coalesce_usecs = coalesce->tx_coalesce_usecs;
+       else
+               lif->tx_coalesce_usecs = coalesce->rx_coalesce_usecs;
+       if (tx_coal != lif->tx_coalesce_hw) {
+               lif->tx_coalesce_hw = tx_coal;
+
+               if (test_bit(IONIC_LIF_F_UP, lif->state)) {
+                       for (i = 0; i < lif->nxqs; i++) {
+                               qcq = lif->txqcqs[i].qcq;
+                               ionic_intr_coal_init(lif->ionic->idev.intr_ctrl,
+                                                    qcq->intr.index,
+                                                    lif->tx_coalesce_hw);
+                       }
+               }
+       }
+
        return 0;
 }
 
@@ -510,29 +532,63 @@ static void ionic_get_channels(struct net_device *netdev,
 
        /* report maximum channels */
        ch->max_combined = lif->ionic->ntxqs_per_lif;
+       ch->max_rx = lif->ionic->ntxqs_per_lif / 2;
+       ch->max_tx = lif->ionic->ntxqs_per_lif / 2;
 
        /* report current channels */
-       ch->combined_count = lif->nxqs;
+       if (test_bit(IONIC_LIF_F_SPLIT_INTR, lif->state)) {
+               ch->rx_count = lif->nxqs;
+               ch->tx_count = lif->nxqs;
+       } else {
+               ch->combined_count = lif->nxqs;
+       }
 }
 
 static void ionic_set_queuecount(struct ionic_lif *lif, void *arg)
 {
        struct ethtool_channels *ch = arg;
 
-       lif->nxqs = ch->combined_count;
+       if (ch->combined_count) {
+               lif->nxqs = ch->combined_count;
+               if (test_bit(IONIC_LIF_F_SPLIT_INTR, lif->state)) {
+                       clear_bit(IONIC_LIF_F_SPLIT_INTR, lif->state);
+                       lif->tx_coalesce_usecs = lif->rx_coalesce_usecs;
+                       lif->tx_coalesce_hw = lif->rx_coalesce_hw;
+                       netdev_info(lif->netdev, "Sharing queue interrupts\n");
+               }
+       } else {
+               lif->nxqs = ch->rx_count;
+               if (!test_bit(IONIC_LIF_F_SPLIT_INTR, lif->state)) {
+                       set_bit(IONIC_LIF_F_SPLIT_INTR, lif->state);
+                       netdev_info(lif->netdev, "Splitting queue interrupts\n");
+               }
+       }
 }
 
 static int ionic_set_channels(struct net_device *netdev,
                              struct ethtool_channels *ch)
 {
        struct ionic_lif *lif = netdev_priv(netdev);
+       int new_cnt;
 
-       if (!ch->combined_count || ch->other_count ||
-           ch->rx_count || ch->tx_count)
+       if (ch->rx_count != ch->tx_count) {
+               netdev_info(netdev, "The rx and tx count must be equal\n");
                return -EINVAL;
+       }
 
-       if (ch->combined_count == lif->nxqs)
-               return 0;
+       if (ch->combined_count && ch->rx_count) {
+               netdev_info(netdev, "Use either combined_count or rx/tx_count, not both\n");
+               return -EINVAL;
+       }
+
+       if (ch->combined_count)
+               new_cnt = ch->combined_count;
+       else
+               new_cnt = ch->rx_count;
+
+       if (lif->nxqs != new_cnt)
+               netdev_info(netdev, "Changing queue count from %d to %d\n",
+                           lif->nxqs, new_cnt);
 
        return ionic_reset_queues(lif, ionic_set_queuecount, ch);
 }

diff --git a/drivers/net/ethernet/pensando/ionic/ionic_lif.c b/drivers/net/ethernet/pensando/ionic/ionic_lif.c
index c951ccc17dc4cb1616f0f829467837683122d887..1944bf5264dbb9537ee4075615307f15a41f75ce 100644 (file)
--- a/drivers/net/ethernet/pensando/ionic/ionic_lif.c
+++ b/drivers/net/ethernet/pensando/ionic/ionic_lif.c
@@ -616,7 +616,6 @@ static int ionic_lif_txq_init(struct ionic_lif *lif, struct ionic_qcq *qcq)
                        .index = cpu_to_le32(q->index),
                        .flags = cpu_to_le16(IONIC_QINIT_F_IRQ |
                                             IONIC_QINIT_F_SG),
-                       .intr_index = cpu_to_le16(lif->rxqcqs[q->index].qcq->intr.index),
                        .pid = cpu_to_le16(q->pid),
                        .ring_size = ilog2(q->num_descs),
                        .ring_base = cpu_to_le64(q->base_pa),
@@ -624,14 +623,22 @@ static int ionic_lif_txq_init(struct ionic_lif *lif, struct ionic_qcq *qcq)
                        .sg_ring_base = cpu_to_le64(q->sg_base_pa),
                },
        };
+       unsigned int intr_index;
        int err;
 
+       if (test_bit(IONIC_LIF_F_SPLIT_INTR, lif->state))
+               intr_index = qcq->intr.index;
+       else
+               intr_index = lif->rxqcqs[q->index].qcq->intr.index;
+       ctx.cmd.q_init.intr_index = cpu_to_le16(intr_index);
+
        dev_dbg(dev, "txq_init.pid %d\n", ctx.cmd.q_init.pid);
        dev_dbg(dev, "txq_init.index %d\n", ctx.cmd.q_init.index);
        dev_dbg(dev, "txq_init.ring_base 0x%llx\n", ctx.cmd.q_init.ring_base);
        dev_dbg(dev, "txq_init.ring_size %d\n", ctx.cmd.q_init.ring_size);
        dev_dbg(dev, "txq_init.flags 0x%x\n", ctx.cmd.q_init.flags);
        dev_dbg(dev, "txq_init.ver %d\n", ctx.cmd.q_init.ver);
+       dev_dbg(dev, "txq_init.intr_index %d\n", ctx.cmd.q_init.intr_index);
 
        q->tail = q->info;
        q->head = q->tail;
@@ -648,6 +655,10 @@ static int ionic_lif_txq_init(struct ionic_lif *lif, struct ionic_qcq *qcq)
        dev_dbg(dev, "txq->hw_type %d\n", q->hw_type);
        dev_dbg(dev, "txq->hw_index %d\n", q->hw_index);
 
+       if (test_bit(IONIC_LIF_F_SPLIT_INTR, lif->state))
+               netif_napi_add(lif->netdev, &qcq->napi, ionic_tx_napi,
+                              NAPI_POLL_WEIGHT);
+
        qcq->flags |= IONIC_QCQ_F_INITED;
 
        return 0;
@@ -684,6 +695,7 @@ static int ionic_lif_rxq_init(struct ionic_lif *lif, struct ionic_qcq *qcq)
        dev_dbg(dev, "rxq_init.ring_size %d\n", ctx.cmd.q_init.ring_size);
        dev_dbg(dev, "rxq_init.flags 0x%x\n", ctx.cmd.q_init.flags);
        dev_dbg(dev, "rxq_init.ver %d\n", ctx.cmd.q_init.ver);
+       dev_dbg(dev, "rxq_init.intr_index %d\n", ctx.cmd.q_init.intr_index);
 
        q->tail = q->info;
        q->head = q->tail;
@@ -700,8 +712,12 @@ static int ionic_lif_rxq_init(struct ionic_lif *lif, struct ionic_qcq *qcq)
        dev_dbg(dev, "rxq->hw_type %d\n", q->hw_type);
        dev_dbg(dev, "rxq->hw_index %d\n", q->hw_index);
 
-       netif_napi_add(lif->netdev, &qcq->napi, ionic_rx_napi,
-                      NAPI_POLL_WEIGHT);
+       if (test_bit(IONIC_LIF_F_SPLIT_INTR, lif->state))
+               netif_napi_add(lif->netdev, &qcq->napi, ionic_rx_napi,
+                              NAPI_POLL_WEIGHT);
+       else
+               netif_napi_add(lif->netdev, &qcq->napi, ionic_txrx_napi,
+                              NAPI_POLL_WEIGHT);
 
        qcq->flags |= IONIC_QCQ_F_INITED;
 
@@ -1537,6 +1553,8 @@ static int ionic_txrx_alloc(struct ionic_lif *lif)
                sg_desc_sz = sizeof(struct ionic_txq_sg_desc);
 
        flags = IONIC_QCQ_F_TX_STATS | IONIC_QCQ_F_SG;
+       if (test_bit(IONIC_LIF_F_SPLIT_INTR, lif->state))
+               flags |= IONIC_QCQ_F_INTR;
        for (i = 0; i < lif->nxqs; i++) {
                err = ionic_qcq_alloc(lif, IONIC_QTYPE_TXQ, i, "tx", flags,
                                      lif->ntxq_descs,
@@ -1547,6 +1565,11 @@ static int ionic_txrx_alloc(struct ionic_lif *lif)
                if (err)
                        goto err_out;
 
+               if (flags & IONIC_QCQ_F_INTR)
+                       ionic_intr_coal_init(lif->ionic->idev.intr_ctrl,
+                                            lif->txqcqs[i].qcq->intr.index,
+                                            lif->tx_coalesce_hw);
+
                lif->txqcqs[i].qcq->stats = lif->txqcqs[i].stats;
                ionic_debugfs_add_qcq(lif, lif->txqcqs[i].qcq);
        }
@@ -1562,13 +1585,15 @@ static int ionic_txrx_alloc(struct ionic_lif *lif)
                if (err)
                        goto err_out;
 
-               lif->rxqcqs[i].qcq->stats = lif->rxqcqs[i].stats;
-
                ionic_intr_coal_init(lif->ionic->idev.intr_ctrl,
                                     lif->rxqcqs[i].qcq->intr.index,
                                     lif->rx_coalesce_hw);
-               ionic_link_qcq_interrupts(lif->rxqcqs[i].qcq,
-                                         lif->txqcqs[i].qcq);
+
+               if (!test_bit(IONIC_LIF_F_SPLIT_INTR, lif->state))
+                       ionic_link_qcq_interrupts(lif->rxqcqs[i].qcq,
+                                                 lif->txqcqs[i].qcq);
+
+               lif->rxqcqs[i].qcq->stats = lif->rxqcqs[i].stats;
                ionic_debugfs_add_qcq(lif, lif->rxqcqs[i].qcq);
        }
 
@@ -2071,6 +2096,8 @@ static struct ionic_lif *ionic_lif_alloc(struct ionic *ionic, unsigned int index
        lif->rx_coalesce_usecs = IONIC_ITR_COAL_USEC_DEFAULT;
        lif->rx_coalesce_hw = ionic_coal_usec_to_hw(lif->ionic,
                                                    lif->rx_coalesce_usecs);
+       lif->tx_coalesce_usecs = lif->rx_coalesce_usecs;
+       lif->tx_coalesce_hw = lif->rx_coalesce_hw;
 
        snprintf(lif->name, sizeof(lif->name), "lif%u", index);
 

diff --git a/drivers/net/ethernet/pensando/ionic/ionic_lif.h b/drivers/net/ethernet/pensando/ionic/ionic_lif.h
index 13f173d83970ba3f87f5a50effbf7fbcf781859a..1ee3b14c8d50c7822d3f32b1855f84542343be27 100644 (file)
--- a/drivers/net/ethernet/pensando/ionic/ionic_lif.h
+++ b/drivers/net/ethernet/pensando/ionic/ionic_lif.h
@@ -137,6 +137,7 @@ enum ionic_lif_state_flags {
        IONIC_LIF_F_UP,
        IONIC_LIF_F_LINK_CHECK_REQUESTED,
        IONIC_LIF_F_FW_RESET,
+       IONIC_LIF_F_SPLIT_INTR,
 
        /* leave this as last */
        IONIC_LIF_F_STATE_SIZE
@@ -205,6 +206,8 @@ struct ionic_lif {
        struct dentry *dentry;
        u32 rx_coalesce_usecs;          /* what the user asked for */
        u32 rx_coalesce_hw;             /* what the hw is using */
+       u32 tx_coalesce_usecs;          /* what the user asked for */
+       u32 tx_coalesce_hw;             /* what the hw is using */
 
        struct work_struct tx_timeout_work;
 };

diff --git a/drivers/net/ethernet/pensando/ionic/ionic_txrx.c b/drivers/net/ethernet/pensando/ionic/ionic_txrx.c
index 766f4595895ccf861e92ca8929eaf6c2ce6fe3f3..8107d32c27673a2b8b8aa015a9198668ec040dfe 100644 (file)
--- a/drivers/net/ethernet/pensando/ionic/ionic_txrx.c
+++ b/drivers/net/ethernet/pensando/ionic/ionic_txrx.c
@@ -419,7 +419,74 @@ void ionic_rx_empty(struct ionic_queue *q)
        }
 }
 
+int ionic_tx_napi(struct napi_struct *napi, int budget)
+{
+       struct ionic_qcq *qcq = napi_to_qcq(napi);
+       struct ionic_cq *cq = napi_to_cq(napi);
+       struct ionic_dev *idev;
+       struct ionic_lif *lif;
+       u32 work_done = 0;
+       u32 flags = 0;
+
+       lif = cq->bound_q->lif;
+       idev = &lif->ionic->idev;
+
+       work_done = ionic_cq_service(cq, budget,
+                                    ionic_tx_service, NULL, NULL);
+
+       if (work_done < budget && napi_complete_done(napi, work_done)) {
+               flags |= IONIC_INTR_CRED_UNMASK;
+               DEBUG_STATS_INTR_REARM(cq->bound_intr);
+       }
+
+       if (work_done || flags) {
+               flags |= IONIC_INTR_CRED_RESET_COALESCE;
+               ionic_intr_credits(idev->intr_ctrl,
+                                  cq->bound_intr->index,
+                                  work_done, flags);
+       }
+
+       DEBUG_STATS_NAPI_POLL(qcq, work_done);
+
+       return work_done;
+}
+
 int ionic_rx_napi(struct napi_struct *napi, int budget)
+{
+       struct ionic_qcq *qcq = napi_to_qcq(napi);
+       struct ionic_cq *cq = napi_to_cq(napi);
+       struct ionic_dev *idev;
+       struct ionic_lif *lif;
+       u32 work_done = 0;
+       u32 flags = 0;
+
+       lif = cq->bound_q->lif;
+       idev = &lif->ionic->idev;
+
+       work_done = ionic_cq_service(cq, budget,
+                                    ionic_rx_service, NULL, NULL);
+
+       if (work_done)
+               ionic_rx_fill(cq->bound_q);
+
+       if (work_done < budget && napi_complete_done(napi, work_done)) {
+               flags |= IONIC_INTR_CRED_UNMASK;
+               DEBUG_STATS_INTR_REARM(cq->bound_intr);
+       }
+
+       if (work_done || flags) {
+               flags |= IONIC_INTR_CRED_RESET_COALESCE;
+               ionic_intr_credits(idev->intr_ctrl,
+                                  cq->bound_intr->index,
+                                  work_done, flags);
+       }
+
+       DEBUG_STATS_NAPI_POLL(qcq, work_done);
+
+       return work_done;
+}
+
+int ionic_txrx_napi(struct napi_struct *napi, int budget)
 {
        struct ionic_qcq *qcq = napi_to_qcq(napi);
        struct ionic_cq *rxcq = napi_to_cq(napi);

diff --git a/drivers/net/ethernet/pensando/ionic/ionic_txrx.h b/drivers/net/ethernet/pensando/ionic/ionic_txrx.h
index 71973e3c35a6892893828a2d0fd7fd303e016954..a5883be0413f6da4e6bbef642f049521182e382c 100644 (file)
--- a/drivers/net/ethernet/pensando/ionic/ionic_txrx.h
+++ b/drivers/net/ethernet/pensando/ionic/ionic_txrx.h
@@ -11,6 +11,8 @@ void ionic_rx_fill(struct ionic_queue *q);
 void ionic_rx_empty(struct ionic_queue *q);
 void ionic_tx_empty(struct ionic_queue *q);
 int ionic_rx_napi(struct napi_struct *napi, int budget);
+int ionic_tx_napi(struct napi_struct *napi, int budget);
+int ionic_txrx_napi(struct napi_struct *napi, int budget);
 netdev_tx_t ionic_start_xmit(struct sk_buff *skb, struct net_device *netdev);
 
 #endif /* _IONIC_TXRX_H_ */