qcacmn: Add watchdog timer for WMI work queue lock-up

WMI work queue rx context can block other work queue
shared on the same CPU if it takes more time.

Add watchdog timer for WMI work queue housekeeping and
assert if takes more time in SLUB DEBUG build

Change-Id: I60b1dad21afbf93a5b88aa855a2835bb0f85b82f
CRs-Fixed: 2104106

wmi/src/wmi_unified.c

@@ -2473,6 +2473,30 @@ end:
 
 }
 
+#define WMI_WQ_WD_TIMEOUT (10 * 1000) /* 10s */
+
+static inline void wmi_workqueue_watchdog_warn(uint16_t msg_type_id)
+{
+	QDF_TRACE(QDF_MODULE_ID_QDF, QDF_TRACE_LEVEL_ERROR,
+		  "%s: Message type %x has exceeded its alloted time of %ds",
+		  __func__, msg_type_id, WMI_WQ_WD_TIMEOUT / 1000);
+}
+
+#ifdef CONFIG_SLUB_DEBUG_ON
+static void wmi_workqueue_watchdog_bite(void *arg)
+{
+	wmi_workqueue_watchdog_warn(*(uint16_t *)arg);
+	QDF_TRACE(QDF_MODULE_ID_QDF, QDF_TRACE_LEVEL_ERROR,
+		  "%s: Going down for WMI WQ Watchdog Bite!", __func__);
+	QDF_BUG(0);
+}
+#else
+static inline void wmi_workqueue_watchdog_bite(void *arg)
+{
+	wmi_workqueue_watchdog_warn(*(uint16_t *)arg);
+}
+#endif
+
 /**
  * wmi_rx_event_work() - process rx event in rx work queue context
  * @arg: opaque pointer to wmi handle
@@ -2485,16 +2509,26 @@ static void wmi_rx_event_work(void *arg)
 {
 	wmi_buf_t buf;
 	struct wmi_unified *wmi = arg;
+	qdf_timer_t wd_timer;
+	uint16_t wd_msg_type_id;
 
+	/* initialize WMI workqueue watchdog timer */
+	qdf_timer_init(NULL, &wd_timer, &wmi_workqueue_watchdog_bite,
+			&wd_msg_type_id, QDF_TIMER_TYPE_SW);
 	qdf_spin_lock_bh(&wmi->eventq_lock);
 	buf = qdf_nbuf_queue_remove(&wmi->event_queue);
 	qdf_spin_unlock_bh(&wmi->eventq_lock);
 	while (buf) {
+		qdf_timer_start(&wd_timer, WMI_WQ_WD_TIMEOUT);
+		wd_msg_type_id =
+		   WMI_GET_FIELD(qdf_nbuf_data(buf), WMI_CMD_HDR, COMMANDID);
 		__wmi_control_rx(wmi, buf);
+		qdf_timer_stop(&wd_timer);
 		qdf_spin_lock_bh(&wmi->eventq_lock);
 		buf = qdf_nbuf_queue_remove(&wmi->event_queue);
 		qdf_spin_unlock_bh(&wmi->eventq_lock);
 	}
+	qdf_timer_free(&wd_timer);
 }
 
 #ifdef FEATURE_RUNTIME_PM