[RFC] clocksource: dummy: don't show message on first cs read

[Antony Pavlov]

In the commit

    commit 96cae61eba199b9c3f5451f293cf60db2b535164
    Author: Sascha Hauer <s.hauer at pengutronix.de>
    Date:   Tue Sep 30 08:25:55 2014 +0200

        clock: Add a variable with the first timestamp after startup

        For measuring the startup time it's useful to save the first
        timestamp after the clocksource has been registered.

the behaviour of clocksource subsystem is changed: every registered
clocksource is called at least once. So the dummy clocksource (if enabled)
_ALWAYS_ prints a confusing 'Using dummy clocksource' warning.

This patch fixes the situation: now the 'Using dummy clocksource'
warning is printed only if the dummy clocksource is called second time.

Signed-off-by: Antony Pavlov <antonynpavlov at gmail.com>
---
 drivers/clocksource/dummy.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/clocksource/dummy.c b/drivers/clocksource/dummy.c
index 96f9b6e..9a42305 100644
--- a/drivers/clocksource/dummy.c
+++ b/drivers/clocksource/dummy.c
@@ -25,8 +25,11 @@ static uint64_t dummy_cs_read(void)
 {
 	static int first;
 
-	if (!first) {
+	if (first == 1) {
 		pr_warn("Warning: Using dummy clocksource\n");
+		first = 2;
+	}
+	if (!first) {
 		first = 1;
 	}
 
-- 
2.1.1