From d36c4857cbaede959e012045711a3467e857e132 Mon Sep 17 00:00:00 2001
From: Sameer Wadgaonkar <sameer.wadgaonkar@unisys.com>
Date: Fri, 19 May 2017 16:17:58 -0400
Subject: [PATCH] staging: unisys: visorbus: add comment to explain polling
logic in controlvm_periodic_work
Added a comment to explain polling frequency variation logic in
controlvm_periodic_logic() in visorchipset.c.
Signed-off-by: Sameer Wadgaonkar <sameer.wadgaonkar@unisys.com>
Reported-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: David Kershner <david.kershner@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/staging/unisys/visorbus/visorchipset.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/drivers/staging/unisys/visorbus/visorchipset.c b/drivers/staging/unisys/visorbus/visorchipset.c
index c40a3701670a..8438b717b7b6 100644
--- a/drivers/staging/unisys/visorbus/visorchipset.c
+++ b/drivers/staging/unisys/visorbus/visorchipset.c
@@ -1787,6 +1787,11 @@ controlvm_periodic_work(struct work_struct *work)
/* parahotplug_worker */
parahotplug_process_list();
+/*
+ * The controlvm messages are sent in a bulk. If we start receiving messages, we
+ * want the polling to be fast. If we do not receive any message for
+ * MIN_IDLE_SECONDS, we can slow down the polling.
+ */
schedule_out:
if (time_after(jiffies, chipset_dev->most_recent_message_jiffies +
(HZ * MIN_IDLE_SECONDS))) {
--
2.30.9