[PATCH 3/3] time: clocksource: Add a comment to CLOCK_SOURCE_SUSPEND_NONSTOP

From: Xunlei Pang
Date: Tue Jan 20 2015 - 11:49:51 EST


When doing timekeeping_resume(), if the nonstop clocksource wraps
back, "cycle_delta" will miss the wrap time.

So add a comment to indicate that if have this flag set, you are
aware that this nonstop clocksource won't wrap during suspension.

Signed-off-by: Xunlei Pang <pang.xunlei@xxxxxxxxxx>
---
include/linux/clocksource.h | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index abcafaa..20bca76 100644
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -207,6 +207,11 @@ struct clocksource {
#define CLOCK_SOURCE_WATCHDOG 0x10
#define CLOCK_SOURCE_VALID_FOR_HRES 0x20
#define CLOCK_SOURCE_UNSTABLE 0x40
+
+/*
+ * Setting this flag, also means it doesn't wrap back during
+ * system suspend/resume. See timekeeping_resume().
+ */
#define CLOCK_SOURCE_SUSPEND_NONSTOP 0x80
#define CLOCK_SOURCE_RESELECT 0x100

--
1.9.1

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