[PATCH net-next 1/7] timecounter: provide a macro to initialize the cyclecounter mask field.

From: Richard Cochran
Date: Thu Jan 01 2015 - 05:45:53 EST


There is no need for users of the timecounter/cyclecounter code to include
clocksource.h just for a single macro.

Signed-off-by: Richard Cochran <richardcochran@xxxxxxxxx>
---
include/linux/timecounter.h | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/include/linux/timecounter.h b/include/linux/timecounter.h
index 74f4549..4382035 100644
--- a/include/linux/timecounter.h
+++ b/include/linux/timecounter.h
@@ -19,6 +19,9 @@

#include <linux/types.h>

+/* simplify initialization of mask field */
+#define CYCLECOUNTER_MASK(bits) (cycle_t)((bits) < 64 ? ((1ULL<<(bits))-1) : -1)
+
/**
* struct cyclecounter - hardware abstraction for a free running counter
* Provides completely state-free accessors to the underlying hardware.
@@ -29,7 +32,7 @@
* @read: returns the current cycle value
* @mask: bitmask for two's complement
* subtraction of non 64 bit counters,
- * see CLOCKSOURCE_MASK() helper macro
+ * see CYCLECOUNTER_MASK() helper macro
* @mult: cycle to nanosecond multiplier
* @shift: cycle to nanosecond divisor (power of two)
*/
--
1.7.10.4

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