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authorSteve French <sfrench@us.ibm.com>2011-01-10 02:18:16 +0300
committerSteve French <sfrench@us.ibm.com>2011-01-10 02:18:16 +0300
commitacc6f11272ce4f77c40b1a6292eb198fd6aaf8c3 (patch)
tree2da3a61b6726707a89f1cf93446aabd2fb00e1f0 /include/linux/average.h
parent7e12eddb73d4f288b0339ee13832a34d6bc4fd90 (diff)
parent0c21e3aaf6ae85bee804a325aa29c325209180fd (diff)
downloadlinux-acc6f11272ce4f77c40b1a6292eb198fd6aaf8c3.tar.xz
Merge branch 'master' of /pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts: fs/cifs/dir.c
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 */