net: napi_schedule_rps() cleanup

napi_schedule_rps() return value is ignored, remove it.

Change the comment to clarify the intent.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Tested-by: Jason Xing <kerneljasonxing@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net/core/dev.c

@@ -4582,11 +4582,18 @@ static void trigger_rx_softirq(void *data)
 }
 
 /*
- * Check if this softnet_data structure is another cpu one
- * If yes, queue it to our IPI list and return 1
- * If no, return 0
+ * After we queued a packet into sd->input_pkt_queue,
+ * we need to make sure this queue is serviced soon.
+ *
+ * - If this is another cpu queue, link it to our rps_ipi_list,
+ *   and make sure we will process rps_ipi_list from net_rx_action().
+ *   As we do not know yet if we are called from net_rx_action(),
+ *   we have to raise NET_RX_SOFTIRQ. This might change in the future.
+ *
+ * - If this is our own queue, NAPI schedule our backlog.
+ *   Note that this also raises NET_RX_SOFTIRQ.
  */
-static int napi_schedule_rps(struct softnet_data *sd)
+static void napi_schedule_rps(struct softnet_data *sd)
 {
 	struct softnet_data *mysd = this_cpu_ptr(&softnet_data);
 
@@ -4596,11 +4603,10 @@ static int napi_schedule_rps(struct softnet_data *sd)
 		mysd->rps_ipi_list = sd;
 
 		__raise_softirq_irqoff(NET_RX_SOFTIRQ);
-		return 1;
+		return;
 	}
 #endif /* CONFIG_RPS */
 	__napi_schedule_irqoff(&mysd->backlog);
-	return 0;
 }
 
 #ifdef CONFIG_NET_FLOW_LIMIT