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authorJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-11 10:41:07 +0300
committerJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-13 08:17:18 +0300
commite09b41010ba33a20a87472ee821fa407a5b8da36 (patch)
treed10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/include/linux/average.h
parentf93b97fd65072de626c074dbe099a1fff05ce060 (diff)
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page. During the rebasing, the following patch collided: Force tick interrupt and get rid of softirq magic(I70131fb85). Collisions have been removed because its logic was found on the source already. Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769 Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/include/linux/average.h')
-rw-r--r--kernel/include/linux/average.h61
1 files changed, 38 insertions, 23 deletions
diff --git a/kernel/include/linux/average.h b/kernel/include/linux/average.h
index c6028fd74..d04aa5828 100644
--- a/kernel/include/linux/average.h
+++ b/kernel/include/linux/average.h
@@ -3,28 +3,43 @@
/* Exponentially weighted moving average (EWMA) */
-/* For more documentation see lib/average.c */
-
-struct ewma {
- unsigned long internal;
- unsigned long factor;
- unsigned long weight;
-};
-
-extern void ewma_init(struct ewma *avg, unsigned long factor,
- unsigned long weight);
-
-extern struct ewma *ewma_add(struct ewma *avg, unsigned long val);
-
-/**
- * ewma_read() - Get average value
- * @avg: Average structure
- *
- * Returns the average value held in @avg.
- */
-static inline unsigned long ewma_read(const struct ewma *avg)
-{
- return avg->internal >> avg->factor;
-}
+#define DECLARE_EWMA(name, _factor, _weight) \
+ struct ewma_##name { \
+ unsigned long internal; \
+ }; \
+ static inline void ewma_##name##_init(struct ewma_##name *e) \
+ { \
+ BUILD_BUG_ON(!__builtin_constant_p(_factor)); \
+ BUILD_BUG_ON(!__builtin_constant_p(_weight)); \
+ BUILD_BUG_ON_NOT_POWER_OF_2(_factor); \
+ BUILD_BUG_ON_NOT_POWER_OF_2(_weight); \
+ e->internal = 0; \
+ } \
+ static inline unsigned long \
+ ewma_##name##_read(struct ewma_##name *e) \
+ { \
+ BUILD_BUG_ON(!__builtin_constant_p(_factor)); \
+ BUILD_BUG_ON(!__builtin_constant_p(_weight)); \
+ BUILD_BUG_ON_NOT_POWER_OF_2(_factor); \
+ BUILD_BUG_ON_NOT_POWER_OF_2(_weight); \
+ return e->internal >> ilog2(_factor); \
+ } \
+ static inline void ewma_##name##_add(struct ewma_##name *e, \
+ unsigned long val) \
+ { \
+ unsigned long internal = ACCESS_ONCE(e->internal); \
+ unsigned long weight = ilog2(_weight); \
+ unsigned long factor = ilog2(_factor); \
+ \
+ BUILD_BUG_ON(!__builtin_constant_p(_factor)); \
+ BUILD_BUG_ON(!__builtin_constant_p(_weight)); \
+ BUILD_BUG_ON_NOT_POWER_OF_2(_factor); \
+ BUILD_BUG_ON_NOT_POWER_OF_2(_weight); \
+ \
+ ACCESS_ONCE(e->internal) = internal ? \
+ (((internal << weight) - internal) + \
+ (val << factor)) >> weight : \
+ (val << factor); \
+ }
#endif /* _LINUX_AVERAGE_H */