net/sfc: support link status change interrupt
authorAndrew Rybchenko <arybchenko@solarflare.com>
Thu, 15 Dec 2016 12:50:57 +0000 (12:50 +0000)
committerFerruh Yigit <ferruh.yigit@intel.com>
Tue, 17 Jan 2017 18:40:50 +0000 (19:40 +0100)
Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
Reviewed-by: Andrew Lee <alee@solarflare.com>
Reviewed-by: Robert Stonehouse <rstonehouse@solarflare.com>
doc/guides/nics/features/sfc_efx.ini
doc/guides/nics/sfc_efx.rst
drivers/net/sfc/sfc.c
drivers/net/sfc/sfc.h
drivers/net/sfc/sfc_ethdev.c
drivers/net/sfc/sfc_ev.c
drivers/net/sfc/sfc_intr.c

index 25472f8..693d35e 100644 (file)
@@ -5,6 +5,7 @@
 ;
 [Features]
 Link status          = Y
+Link status event    = Y
 Flow control         = Y
 L3 checksum offload  = P
 L4 checksum offload  = P
index 06b0c14..58f8242 100644 (file)
@@ -44,7 +44,7 @@ SFC EFX PMD has support for:
 
 - Multiple transmit and receive queues
 
-- Link state information
+- Link state information including link status change interrupt
 
 - IPv4/IPv6 TCP/UDP transmit checksum offload
 
@@ -61,8 +61,6 @@ Non-supported Features
 
 The features not yet supported include:
 
-- Link status change interrupt
-
 - Receive queue interupts
 
 - Priority-based flow control
index 4757e39..6b3dc48 100644 (file)
@@ -116,7 +116,9 @@ sfc_check_conf(struct sfc_adapter *sa)
                rc = EINVAL;
        }
 
-       if (conf->intr_conf.lsc != 0) {
+       if ((conf->intr_conf.lsc != 0) &&
+           (sa->intr.type != EFX_INTR_LINE) &&
+           (sa->intr.type != EFX_INTR_MESSAGE)) {
                sfc_err(sa, "Link status change interrupt not supported");
                rc = EINVAL;
        }
index 913da8c..83c4430 100644 (file)
@@ -115,6 +115,8 @@ struct sfc_mcdi {
 
 struct sfc_intr {
        efx_intr_type_t                 type;
+       rte_intr_callback_fn            handler;
+       boolean_t                       lsc_intr;
 };
 
 struct sfc_evq_info;
@@ -122,6 +124,8 @@ struct sfc_rxq_info;
 struct sfc_txq_info;
 
 struct sfc_port {
+       unsigned int                    lsc_seq;
+
        unsigned int                    flow_ctrl;
        boolean_t                       flow_ctrl_autoneg;
        size_t                          pdu;
index 0fb5e32..4308dbb 100644 (file)
@@ -681,6 +681,7 @@ static struct eth_driver sfc_efx_pmd = {
        .pci_drv = {
                .id_table = pci_id_sfc_efx_map,
                .drv_flags =
+                       RTE_PCI_DRV_INTR_LSC |
                        RTE_PCI_DRV_NEED_MAPPING,
                .probe = rte_eth_dev_pci_probe,
                .remove = rte_eth_dev_pci_remove,
index de42845..c788986 100644 (file)
@@ -287,11 +287,25 @@ sfc_ev_link_change(void *arg, efx_link_mode_t link_mode)
        struct sfc_adapter *sa = evq->sa;
        struct rte_eth_link *dev_link = &sa->eth_dev->data->dev_link;
        struct rte_eth_link new_link;
+       uint64_t new_link_u64;
+       uint64_t old_link_u64;
 
        EFX_STATIC_ASSERT(sizeof(*dev_link) == sizeof(rte_atomic64_t));
 
        sfc_port_link_mode_to_info(link_mode, &new_link);
-       rte_atomic64_set((rte_atomic64_t *)dev_link, *(uint64_t *)&new_link);
+
+       new_link_u64 = *(uint64_t *)&new_link;
+       do {
+               old_link_u64 = rte_atomic64_read((rte_atomic64_t *)dev_link);
+               if (old_link_u64 == new_link_u64)
+                       break;
+
+               if (rte_atomic64_cmpset((volatile uint64_t *)dev_link,
+                                       old_link_u64, new_link_u64)) {
+                       evq->sa->port.lsc_seq++;
+                       break;
+               }
+       } while (B_TRUE);
 
        return B_FALSE;
 }
@@ -521,6 +535,12 @@ sfc_ev_start(struct sfc_adapter *sa)
        if (rc != 0)
                goto fail_mgmt_evq_start;
 
+       if (sa->intr.lsc_intr) {
+               rc = sfc_ev_qprime(sa->evq_info[sa->mgmt_evq_index].evq);
+               if (rc != 0)
+                       goto fail_evq0_prime;
+       }
+
        rte_spinlock_unlock(&sa->mgmt_evq_lock);
 
        /*
@@ -538,6 +558,9 @@ sfc_ev_start(struct sfc_adapter *sa)
 
        return 0;
 
+fail_evq0_prime:
+       sfc_ev_qstop(sa, 0);
+
 fail_mgmt_evq_start:
        rte_spinlock_unlock(&sa->mgmt_evq_lock);
        efx_ev_fini(sa->nic);
@@ -639,7 +662,10 @@ sfc_ev_qinit_info(struct sfc_adapter *sa, unsigned int sw_index)
        SFC_ASSERT(rte_is_power_of_2(max_entries));
 
        evq_info->max_entries = max_entries;
-       evq_info->flags = sa->evq_flags | EFX_EVQ_FLAGS_NOTIFY_DISABLED;
+       evq_info->flags = sa->evq_flags |
+               ((sa->intr.lsc_intr && sw_index == sa->mgmt_evq_index) ?
+                       EFX_EVQ_FLAGS_NOTIFY_INTERRUPT :
+                       EFX_EVQ_FLAGS_NOTIFY_DISABLED);
 
        return 0;
 }
index 622b7cb..d06980e 100644 (file)
  * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+/*
+ * At the momemt of writing DPDK v16.07 has notion of two types of
+ * interrupts: LSC (link status change) and RXQ (receive indication).
+ * It allows to register interrupt callback for entire device which is
+ * not intended to be used for receive indication (i.e. link status
+ * change indication only). The handler has no information which HW
+ * interrupt has triggered it, so we don't know which event queue should
+ * be polled/reprimed (except qmask in the case of legacy line interrupt).
+ */
+
+#include <rte_common.h>
+#include <rte_interrupts.h>
+
 #include "efx.h"
 
 #include "sfc.h"
 #include "sfc_log.h"
+#include "sfc_ev.h"
+
+static void
+sfc_intr_handle_mgmt_evq(struct sfc_adapter *sa)
+{
+       struct sfc_evq *evq;
+
+       rte_spinlock_lock(&sa->mgmt_evq_lock);
+
+       evq = sa->evq_info[sa->mgmt_evq_index].evq;
+
+       if (evq->init_state != SFC_EVQ_STARTED) {
+               sfc_log_init(sa, "interrupt on stopped EVQ %u", evq->evq_index);
+       } else {
+               sfc_ev_qpoll(evq);
+
+               if (sfc_ev_qprime(evq) != 0)
+                       sfc_err(sa, "cannot prime EVQ %u", evq->evq_index);
+       }
+
+       rte_spinlock_unlock(&sa->mgmt_evq_lock);
+}
+
+static void
+sfc_intr_line_handler(struct rte_intr_handle *intr_handle, void *cb_arg)
+{
+       struct sfc_adapter *sa = (struct sfc_adapter *)cb_arg;
+       efx_nic_t *enp = sa->nic;
+       boolean_t fatal;
+       uint32_t qmask;
+       unsigned int lsc_seq = sa->port.lsc_seq;
+
+       sfc_log_init(sa, "entry");
+
+       if (sa->state != SFC_ADAPTER_STARTED &&
+           sa->state != SFC_ADAPTER_STARTING &&
+           sa->state != SFC_ADAPTER_STOPPING) {
+               sfc_log_init(sa,
+                            "interrupt on stopped adapter, don't reenable");
+               goto exit;
+       }
+
+       efx_intr_status_line(enp, &fatal, &qmask);
+       if (fatal) {
+               (void)efx_intr_disable(enp);
+               (void)efx_intr_fatal(enp);
+               sfc_err(sa, "fatal, interrupts disabled");
+               goto exit;
+       }
+
+       if (qmask & (1 << sa->mgmt_evq_index))
+               sfc_intr_handle_mgmt_evq(sa);
+
+       if (rte_intr_enable(intr_handle) != 0)
+               sfc_err(sa, "cannot reenable interrupts");
+
+       sfc_log_init(sa, "done");
+
+exit:
+       if (lsc_seq != sa->port.lsc_seq) {
+               sfc_info(sa, "link status change event: link %s",
+                        sa->eth_dev->data->dev_link.link_status ?
+                        "UP" : "DOWN");
+               _rte_eth_dev_callback_process(sa->eth_dev,
+                                             RTE_ETH_EVENT_INTR_LSC, NULL);
+       }
+}
+
+static void
+sfc_intr_message_handler(struct rte_intr_handle *intr_handle, void *cb_arg)
+{
+       struct sfc_adapter *sa = (struct sfc_adapter *)cb_arg;
+       efx_nic_t *enp = sa->nic;
+       boolean_t fatal;
+       unsigned int lsc_seq = sa->port.lsc_seq;
+
+       sfc_log_init(sa, "entry");
+
+       if (sa->state != SFC_ADAPTER_STARTED &&
+           sa->state != SFC_ADAPTER_STARTING &&
+           sa->state != SFC_ADAPTER_STOPPING) {
+               sfc_log_init(sa, "adapter not-started, don't reenable");
+               goto exit;
+       }
+
+       efx_intr_status_message(enp, sa->mgmt_evq_index, &fatal);
+       if (fatal) {
+               (void)efx_intr_disable(enp);
+               (void)efx_intr_fatal(enp);
+               sfc_err(sa, "fatal, interrupts disabled");
+               goto exit;
+       }
+
+       sfc_intr_handle_mgmt_evq(sa);
+
+       if (rte_intr_enable(intr_handle) != 0)
+               sfc_err(sa, "cannot reenable interrupts");
+
+       sfc_log_init(sa, "done");
+
+exit:
+       if (lsc_seq != sa->port.lsc_seq) {
+               sfc_info(sa, "link status change event");
+               _rte_eth_dev_callback_process(sa->eth_dev,
+                                             RTE_ETH_EVENT_INTR_LSC, NULL);
+       }
+}
 
 int
 sfc_intr_start(struct sfc_adapter *sa)
@@ -56,11 +176,49 @@ sfc_intr_start(struct sfc_adapter *sa)
        pci_dev = SFC_DEV_TO_PCI(sa->eth_dev);
        intr_handle = &pci_dev->intr_handle;
 
+       if (intr->handler != NULL) {
+               sfc_log_init(sa, "rte_intr_callback_register");
+               rc = rte_intr_callback_register(intr_handle, intr->handler,
+                                               (void *)sa);
+               if (rc != 0) {
+                       sfc_err(sa,
+                               "cannot register interrupt handler (rc=%d)",
+                               rc);
+                       /*
+                        * Convert error code from negative returned by RTE API
+                        * to positive used in the driver.
+                        */
+                       rc = -rc;
+                       goto fail_rte_intr_cb_reg;
+               }
+
+               sfc_log_init(sa, "rte_intr_enable");
+               rc = rte_intr_enable(intr_handle);
+               if (rc != 0) {
+                       sfc_err(sa, "cannot enable interrupts (rc=%d)", rc);
+                       /*
+                        * Convert error code from negative returned by RTE API
+                        * to positive used in the driver.
+                        */
+                       rc = -rc;
+                       goto fail_rte_intr_enable;
+               }
+
+               sfc_log_init(sa, "efx_intr_enable");
+               efx_intr_enable(sa->nic);
+       }
+
        sfc_log_init(sa, "done type=%u max_intr=%d nb_efd=%u vec=%p",
                     intr_handle->type, intr_handle->max_intr,
                     intr_handle->nb_efd, intr_handle->intr_vec);
        return 0;
 
+fail_rte_intr_enable:
+       rte_intr_callback_unregister(intr_handle, intr->handler, (void *)sa);
+
+fail_rte_intr_cb_reg:
+       efx_intr_fini(sa->nic);
+
 fail_intr_init:
        sfc_log_init(sa, "failed %d", rc);
        return rc;
@@ -69,8 +227,30 @@ fail_intr_init:
 void
 sfc_intr_stop(struct sfc_adapter *sa)
 {
+       struct sfc_intr *intr = &sa->intr;
+       struct rte_pci_device *pci_dev = SFC_DEV_TO_PCI(sa->eth_dev);
+
        sfc_log_init(sa, "entry");
 
+       if (intr->handler != NULL) {
+               struct rte_intr_handle *intr_handle;
+               int rc;
+
+               efx_intr_disable(sa->nic);
+
+               intr_handle = &pci_dev->intr_handle;
+               if (rte_intr_disable(intr_handle) != 0)
+                       sfc_err(sa, "cannot disable interrupts");
+
+               while ((rc = rte_intr_callback_unregister(intr_handle,
+                               intr->handler, (void *)sa)) == -EAGAIN)
+                       ;
+               if (rc != 1)
+                       sfc_err(sa,
+                               "cannot unregister interrupt handler %d",
+                               rc);
+       }
+
        efx_intr_fini(sa->nic);
 
        sfc_log_init(sa, "done");
@@ -79,8 +259,33 @@ sfc_intr_stop(struct sfc_adapter *sa)
 int
 sfc_intr_init(struct sfc_adapter *sa)
 {
+       struct sfc_intr *intr = &sa->intr;
+
        sfc_log_init(sa, "entry");
 
+       intr->handler = NULL;
+       intr->lsc_intr = (sa->eth_dev->data->dev_conf.intr_conf.lsc != 0);
+       if (!intr->lsc_intr) {
+               sfc_info(sa, "LSC tracking using interrupts is disabled");
+               goto done;
+       }
+
+       switch (intr->type) {
+       case EFX_INTR_MESSAGE:
+               intr->handler = sfc_intr_message_handler;
+               break;
+       case EFX_INTR_LINE:
+               intr->handler = sfc_intr_line_handler;
+               break;
+       case EFX_INTR_INVALID:
+               sfc_warn(sa, "interrupts are not supported");
+               break;
+       default:
+               sfc_panic(sa, "unexpected EFX interrupt type %u\n", intr->type);
+               break;
+       }
+
+done:
        sfc_log_init(sa, "done");
        return 0;
 }