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authorDmitry Torokhov <dmitry.torokhov@gmail.com>2011-03-18 23:38:50 -0700
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2011-03-18 23:38:50 -0700
commit97eb3f24352ec6632c2127b35d8087d2a809a9b9 (patch)
tree722948059bbd325bbca232269490124231df80d4 /include/linux/average.h
parent439581ec07fa9cf3f519dd461a2cf41cfd3adcb4 (diff)
parentdef179c271ac9b5020deca798470521f14d11edd (diff)
Merge branch 'next' into for-linus
Diffstat (limited to 'include/linux/average.h')
-rw-r--r--include/linux/average.h30
1 files changed, 30 insertions, 0 deletions
diff --git a/include/linux/average.h b/include/linux/average.h
new file mode 100644
index 000000000000..c6028fd742c1
--- /dev/null
+++ b/include/linux/average.h
@@ -0,0 +1,30 @@
+#ifndef _LINUX_AVERAGE_H
+#define _LINUX_AVERAGE_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 avg->internal >> avg->factor;
+}
+
+#endif /* _LINUX_AVERAGE_H */