qcacld-3.0: avoid free link_stats_results when last cmd isn't complete

For send_ll_stats_req from upper layer,  need send 1 wmi cmd:
WMI_REQUEST_UNIFIED_LL_GET_STA_CMDID,  and need 4 events from F/W
for dbs platform:
1.	radio_stats_event for radio 0
2.	tx_power_level_stats_event for radio 0
3.	radio_stats_event for radio 1
4.	tx_power_level_stats_event  for radio 1.

If new ll_stats_req comes before last send_ll_stats_req finished,
link_stats_results memory wil be freed, left event can't be handled and
last send_ll_stats_req can't get response from low level and time out
after 1.6s,  netlink is blocked during 1.6s,  many app will be blocked.

To fix it, if new ll_stats_req comes before last send_ll_stats_req
finished, don't free link_stats_results memory.

Change-Id: I27453d8a3c72e62b030657323ecdf463114b4ac8
CRs-Fixed: 3106562

core/hdd/src/wlan_hdd_stats.c

@@ -2050,6 +2050,10 @@ static int wlan_hdd_send_ll_stats_req(struct hdd_adapter *adapter,
 
 	hdd_enter_dev(adapter->dev);
 
+	status = wlan_hdd_set_station_stats_request_pending(adapter);
+	if (status == QDF_STATUS_E_ALREADY)
+		return qdf_status_to_os_return(status);
+
 	/*
 	 * FW can send radio stats with multiple events and for the first event
 	 * host allocates memory in wma and processes the events, there is a
@@ -2064,10 +2068,6 @@ static int wlan_hdd_send_ll_stats_req(struct hdd_adapter *adapter,
 	 */
 	sme_radio_tx_mem_free();
 
-	status = wlan_hdd_set_station_stats_request_pending(adapter);
-	if (status == QDF_STATUS_E_ALREADY)
-		return qdf_status_to_os_return(status);
-
 	request = osif_request_alloc(&params);
 	if (!request) {
 		hdd_err("Request Allocation Failure");

core/wma/src/wma_utils.c

@@ -1,6 +1,6 @@
 /*
  * Copyright (c) 2013-2021 The Linux Foundation. All rights reserved.
- * Copyright (c) 2021 Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2021-2022 Qualcomm Innovation Center, Inc. All rights reserved.
  *
  * Permission to use, copy, modify, and/or distribute this software for
  * any purpose with or without fee is hereby granted, provided that the
@@ -1855,6 +1855,8 @@ int wma_unified_radio_tx_mem_free(void *handle)
 
 	if (!wma_handle->link_stats_results)
 		return 0;
+
+	wma_debug("free link_stats_results");
 	qdf_mutex_acquire(&wma_handle->radio_stats_lock);
 	ret = __wma_unified_radio_tx_mem_free(wma_handle);
 	qdf_mutex_release(&wma_handle->radio_stats_lock);