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authorJohn W. Linville <linville@tuxdriver.com>2010-11-24 16:49:20 -0500
committerJohn W. Linville <linville@tuxdriver.com>2010-11-24 16:49:20 -0500
commit51cce8a590c4696d62bfacc63378d1036084cef7 (patch)
treedc24485bdff37ca6a83c69e93ffdbe5c5807b59d /include/linux/average.h
parent2fe66ec242d3f76e3b0101f36419e7e5405bcff3 (diff)
parent4f8559383c41262b50dc758e2e310f257ce6a14d (diff)
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next-2.6 into for-davem
Diffstat (limited to 'include/linux/average.h')
-rw-r--r--include/linux/average.h32
1 files changed, 32 insertions, 0 deletions
diff --git a/include/linux/average.h b/include/linux/average.h
new file mode 100644
index 00000000000..7706e40f95f
--- /dev/null
+++ b/include/linux/average.h
@@ -0,0 +1,32 @@
+#ifndef _LINUX_AVERAGE_H
+#define _LINUX_AVERAGE_H
+
+#include <linux/kernel.h>
+
+/* 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 DIV_ROUND_CLOSEST(avg->internal, avg->factor);
+}
+
+#endif /* _LINUX_AVERAGE_H */