From: Andrea Parri <parri.andrea@gmail.com>
Date: Thu, 9 Jan 2020 17:06:50 +0100
Patch-mainline: v5.6-rc1
Subject: clocksource/drivers/hyper-v: Set TSC clocksource as default w/ InvariantTSC
Git-commit: 9e0333ae38eeb42249e10f95d209244a6e22ac9f
References: bsc#1170620, bsc#1170621

Change the Hyper-V clocksource ratings to 250, below the TSC clocksource
rating of 300.  In configurations where Hyper-V offers an InvariantTSC,
the TSC is not marked "unstable", so the TSC clocksource is available
and preferred.  With the higher rating, it will be the default.  On
older hardware and Hyper-V versions, the TSC is marked "unstable", so no
TSC clocksource is created and the selected Hyper-V clocksource will be
the default.

Signed-off-by: Andrea Parri <parri.andrea@gmail.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200109160650.16150-3-parri.andrea@gmail.com
Acked-by: Olaf Hering <ohering@suse.de>
---
 drivers/clocksource/hyperv_timer.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/clocksource/hyperv_timer.c b/drivers/clocksource/hyperv_timer.c
--- a/drivers/clocksource/hyperv_timer.c
+++ b/drivers/clocksource/hyperv_timer.c
@@ -240,7 +240,7 @@ static u64 read_hv_clock_tsc(struct cloc
 
 static struct clocksource hyperv_cs_tsc = {
 	.name	= "hyperv_clocksource_tsc_page",
-	.rating	= 400,
+	.rating	= 250,
 	.read	= read_hv_clock_tsc,
 	.mask	= CLOCKSOURCE_MASK(64),
 	.flags	= CLOCK_SOURCE_IS_CONTINUOUS,
@@ -266,7 +266,7 @@ static u64 read_hv_clock_msr(struct cloc
 
 static struct clocksource hyperv_cs_msr = {
 	.name	= "hyperv_clocksource_msr",
-	.rating	= 400,
+	.rating	= 250,
 	.read	= read_hv_clock_msr,
 	.mask	= CLOCKSOURCE_MASK(64),
 	.flags	= CLOCK_SOURCE_IS_CONTINUOUS,