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authorDmitry Torokhov <dmitry.torokhov@gmail.com>2011-01-31 21:16:22 -0800
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2011-01-31 21:16:22 -0800
commita1f3d4bba8ea395a39d34ade6017afee8be16031 (patch)
tree874d843d35622f17aa6c3e048e42cf0d679bcb75 /include/linux/average.h
parent723d928417bffff6467da155d8ebbbe016464012 (diff)
parentebf53826e105f488f4f628703a108e98940d1dc5 (diff)
Merge commit 'v2.6.38-rc3' into next
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 */