rtos task can not work when bluetooth connected.

Question

Hi all, 
 
 I creat a main task to process events, when the bluetooth connected, this main task can not work, and the bluetooth can still work. 
 I try to add the main task's priority, but it still unuseful. 
 below is my code: 
 the sdk is nRF5_SDK_15.0.0_a53641a, 
 work on SEGGER Embedded Studio for ARM 4.12, 
 //create main task in main()
UNUSED_VARIABLE(xTaskCreate(user_common_task, "COMMON_TASK", 256*3, NULL, 2, common_task_handle));

//the task function
static void user_common_task(void* arg)
{

	common_irq_Semaphore = xSemaphoreCreateBinary();
	
	for(;;)
	{
 if(xSemaphoreTake(common_irq_Semaphore, portMAX_DELAY ) != pdFALSE)
 {
 uint8_t ret = 0;
 switch (key_evt) 
 {
 case BSP_EVENT_KEY_0:
 DspLog(0xDCCC, 1111);
 break;
 case BSP_EVENT_KEY_0_LONG_PRESS:
 DspLog(0xDeee, 2222);
 if(ble_state == BLE_STATE_IDLE || ble_state == BLE_STATE_INIT)
 {
 hal_user_advertising_start(true);
 }
 break;
 default:
 break;
 }
 }
	}
}

//key event handler, send the semaphore to the main task to process the key event.
static void bsp_evt_handler(bsp_event_t evt)
{

	key_evt = evt;
	BaseType_t xHigherPriorityTaskWoken = pdFALSE;
	xSemaphoreGiveFromISR(common_irq_Semaphore, &xHigherPriorityTaskWoken);

}
--------------------------------------------------------------------------------------
//ble init related called in main(),copy from the example(ble_app_hrs_freertos)
{
	ble_state = BLE_STATE_INIT;
	ble_stack_init();
	gap_params_init();
	gatt_init();
	services_init();
	advertising_init();
	conn_params_init();
	peer_manager_init();

	nrf_sdh_freertos_init(NULL, (void *)0);
}

void nrf_sdh_freertos_init(nrf_sdh_freertos_task_hook_t hook_fn, void * p_context)
{
 NRF_LOG_DEBUG("Creating a SoftDevice task.");

 m_task_hook = hook_fn;

 BaseType_t xReturned = xTaskCreate(softdevice_task,
 "BLE",
 256*3,
 (void *)0,
 2,
 &m_softdevice_task);

	if (xReturned != pdPASS)
 {
 NRF_LOG_ERROR("SoftDevice task not created.");
 APP_ERROR_HANDLER(NRF_ERROR_NO_MEM);
 }
}

/* This function gets events from the SoftDevice and processes them. */
static void softdevice_task(void * pvParameter)
{
 NRF_LOG_DEBUG("Enter softdevice_task.");

 if (m_task_hook != NULL)
 {
 m_task_hook(pvParameter);
 }

 while (true)
 {
 nrf_sdh_evts_poll(); // Let the handlers run first, in case the EVENT occured before creating this task.
 vTaskSuspend(NULL);
 }
}

/**@brief Function for handling BLE events.
 *
 * @param[in] p_ble_evt Bluetooth stack event.
 * @param[in] p_context Unused.
 */
static void ble_evt_handler(ble_evt_t const * p_ble_evt, void * p_context)
{
 ret_code_t err_code = NRF_SUCCESS;
#if 1
 switch (p_ble_evt->header.evt_id)
 {
 case BLE_GAP_EVT_DISCONNECTED:
 ble_state = BLE_STATE_DISCON;
 NRF_LOG_INFO("Disconnected.");
 break;

 case BLE_GAP_EVT_CONNECTED:
 ble_state = BLE_STATE_CON;
 #if 1
 m_conn_handle = p_ble_evt->evt.gap_evt.conn_handle;
 err_code = nrf_ble_qwr_conn_handle_assign(&m_qwr, m_conn_handle);
 APP_ERROR_CHECK(err_code);
 #endif
 break;

 case BLE_GAP_EVT_PHY_UPDATE_REQUEST:
 {
 NRF_LOG_DEBUG("PHY update request.");
 ble_gap_phys_t const phys =
 {
 .rx_phys = BLE_GAP_PHY_AUTO,
 .tx_phys = BLE_GAP_PHY_AUTO,
 };
 err_code = sd_ble_gap_phy_update(p_ble_evt->evt.gap_evt.conn_handle, &phys);
 APP_ERROR_CHECK(err_code);
 } break;

 case BLE_GATTC_EVT_TIMEOUT:
 // Disconnect on GATT Client timeout event.
 NRF_LOG_DEBUG("GATT Client Timeout.");
 err_code = sd_ble_gap_disconnect(p_ble_evt->evt.gattc_evt.conn_handle,
 BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
 APP_ERROR_CHECK(err_code);
 break;

 case BLE_GATTS_EVT_TIMEOUT:
 // Disconnect on GATT Server timeout event.
 NRF_LOG_DEBUG("GATT Server Timeout.");
 err_code = sd_ble_gap_disconnect(p_ble_evt->evt.gatts_evt.conn_handle,
 BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
 APP_ERROR_CHECK(err_code);
 break;

 default:
 // No implementation needed.
 break;
 }
#endif
}
 
 Thanks.