From 2c9f3072fb40cd3ea932449c9af55476e2f398d0 Mon Sep 17 00:00:00 2001
From: Jose Alamos <jose@alamos.cc>
Date: Mon, 22 Aug 2022 01:03:43 +0200
Subject: [PATCH] net/gnrc_netif: add support for priority queues

---
 sys/include/net/gnrc/netif.h                  | 21 ++++++++++++++++++-
 sys/net/gnrc/link_layer/gomach/gomach.c       |  2 +-
 sys/net/gnrc/link_layer/lwmac/lwmac.c         |  2 +-
 sys/net/gnrc/netif/gnrc_netif.c               | 19 +++++++++++++----
 .../gnrc/netif/lorawan/gnrc_netif_lorawan.c   |  2 +-
 5 files changed, 38 insertions(+), 8 deletions(-)

diff --git a/sys/include/net/gnrc/netif.h b/sys/include/net/gnrc/netif.h
index 9247e00f45..923a745539 100644
--- a/sys/include/net/gnrc/netif.h
+++ b/sys/include/net/gnrc/netif.h
@@ -76,6 +76,25 @@
 extern "C" {
 #endif
 
+/**
+ * @brief Index of the high priority queue
+ */
+#define GNRC_NETIF_EVQ_INDEX_PRIO_HIGH  (0)
+
+/**
+ * @brief Index of the low priority queue
+ */
+#if IS_USED(MODULE_BHP_EVENT)
+#define GNRC_NETIF_EVQ_INDEX_PRIO_LOW   (GNRC_NETIF_EVQ_INDEX_PRIO_HIGH + 1)
+#else
+#define GNRC_NETIF_EVQ_INDEX_PRIO_LOW   GNRC_NETIF_EVQ_INDEX_PRIO_HIGH
+#endif
+
+/**
+ * @brief Number of event queues
+ */
+#define GNRC_NETIF_EVQ_NUMOF            (GNRC_NETIF_EVQ_INDEX_PRIO_LOW + 1)
+
 /**
  * @brief   Per-Interface Event Message Buses
  */
@@ -142,7 +161,7 @@ typedef struct {
     /**
      * @brief   Event queue for asynchronous events
      */
-    event_queue_t evq;
+    event_queue_t evq[GNRC_NETIF_EVQ_NUMOF];
     /**
      * @brief   ISR event for the network device
      */
diff --git a/sys/net/gnrc/link_layer/gomach/gomach.c b/sys/net/gnrc/link_layer/gomach/gomach.c
index e4ceaf8c63..90ab50bb13 100644
--- a/sys/net/gnrc/link_layer/gomach/gomach.c
+++ b/sys/net/gnrc/link_layer/gomach/gomach.c
@@ -2030,7 +2030,7 @@ static void _gomach_event_cb(netdev_t *dev, netdev_event_t event)
     gnrc_netif_t *netif = (gnrc_netif_t *) dev->context;
 
     if (event == NETDEV_EVENT_ISR) {
-        event_post(&netif->evq, &netif->event_isr);
+        event_post(&netif->evq[GNRC_NETIF_EVQ_INDEX_PRIO_LOW], &netif->event_isr);
     }
     else {
         DEBUG("gnrc_netdev: event triggered -> %i\n", event);
diff --git a/sys/net/gnrc/link_layer/lwmac/lwmac.c b/sys/net/gnrc/link_layer/lwmac/lwmac.c
index fd5461335f..786ec394d9 100644
--- a/sys/net/gnrc/link_layer/lwmac/lwmac.c
+++ b/sys/net/gnrc/link_layer/lwmac/lwmac.c
@@ -795,7 +795,7 @@ static void _lwmac_event_cb(netdev_t *dev, netdev_event_t event)
     gnrc_netif_t *netif = (gnrc_netif_t *) dev->context;
 
     if (event == NETDEV_EVENT_ISR) {
-        event_post(&netif->evq, &netif->event_isr);
+        event_post(&netif->evq[GNRC_NETIF_EVQ_INDEX_PRIO_LOW], &netif->event_isr);
     }
     else {
         DEBUG("gnrc_netdev: event triggered -> %i\n", event);
diff --git a/sys/net/gnrc/netif/gnrc_netif.c b/sys/net/gnrc/netif/gnrc_netif.c
index 408417c23d..211a02716c 100644
--- a/sys/net/gnrc/netif/gnrc_netif.c
+++ b/sys/net/gnrc/netif/gnrc_netif.c
@@ -1675,6 +1675,18 @@ static void _process_receive_stats(gnrc_netif_t *netdev, gnrc_pktsnip_t *pkt)
     netstats_nb_update_rx(&netdev->netif, src, src_len, hdr->rssi, hdr->lqi);
 }
 
+static event_t *_gnrc_netif_fetch_event(gnrc_netif_t *netif)
+{
+    event_t *ev;
+    /* Iterate from highest priority to lowest priority */
+    for (int i = 0; i < GNRC_NETIF_EVQ_NUMOF; i++) {
+        if ((ev = event_get(&netif->evq[i]))) {
+            return ev;
+        }
+    }
+    return NULL;
+}
+
 /**
  * @brief   Process any pending events and wait for IPC messages
  *
@@ -1697,8 +1709,7 @@ static void _process_events_await_msg(gnrc_netif_t *netif, msg_t *msg)
         event_t *evp;
         /* We can not use event_loop() or event_wait() because then we would not
          * wake up when a message arrives */
-        event_queue_t *evq = &netif->evq;
-        while ((evp = event_get(evq))) {
+        while ((evp = _gnrc_netif_fetch_event(netif))) {
             DEBUG("gnrc_netif: event %p\n", (void *)evp);
             if (evp->handler) {
                 evp->handler(evp);
@@ -1844,7 +1855,7 @@ static void *_gnrc_netif_thread(void *args)
 
     netif->event_isr.handler = _event_handler_isr,
     /* set up the event queue */
-    event_queue_init(&netif->evq);
+    event_queues_init(netif->evq, GNRC_NETIF_EVQ_NUMOF);
 
     /* setup the link-layer's message queue */
     msg_init_queue(msg_queue, GNRC_NETIF_MSG_QUEUE_SIZE);
@@ -1957,7 +1968,7 @@ static void _event_cb(netdev_t *dev, netdev_event_t event)
     gnrc_netif_t *netif = (gnrc_netif_t *) dev->context;
 
     if (event == NETDEV_EVENT_ISR) {
-        event_post(&netif->evq, &netif->event_isr);
+        event_post(&netif->evq[GNRC_NETIF_EVQ_INDEX_PRIO_LOW], &netif->event_isr);
     }
     else {
         DEBUG("gnrc_netif: event triggered -> %i\n", event);
diff --git a/sys/net/gnrc/netif/lorawan/gnrc_netif_lorawan.c b/sys/net/gnrc/netif/lorawan/gnrc_netif_lorawan.c
index d0cf4df17e..8bbdbf4882 100644
--- a/sys/net/gnrc/netif/lorawan/gnrc_netif_lorawan.c
+++ b/sys/net/gnrc/netif/lorawan/gnrc_netif_lorawan.c
@@ -200,7 +200,7 @@ static void _driver_cb(netdev_t *dev, netdev_event_t event)
     gnrc_lorawan_t *mac = &netif->lorawan.mac;
 
     if (event == NETDEV_EVENT_ISR) {
-        event_post(&netif->evq, &netif->event_isr);
+        event_post(&netif->evq[GNRC_NETIF_EVQ_INDEX_PRIO_LOW], &netif->event_isr);
     }
     else {
         DEBUG("gnrc_netif: event triggered -> %i\n", event);