This commit was generated by cvs2svn to compensate for changes in r1650,

[iproute2.git] / tc / tc_estimator.c

diff --git a/tc/tc_estimator.c b/tc/tc_estimator.c
new file mode 100644 (file)
index 0000000..434db0f
--- /dev/null
+++ b/tc/tc_estimator.c
@@ -0,0 +1,44 @@
+/*
+ * tc_core.c           TC core library.
+ *
+ *             This program is free software; you can redistribute it and/or
+ *             modify it under the terms of the GNU General Public License
+ *             as published by the Free Software Foundation; either version
+ *             2 of the License, or (at your option) any later version.
+ *
+ * Authors:    Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <syslog.h>
+#include <fcntl.h>
+#include <math.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <string.h>
+
+#include "tc_core.h"
+
+int tc_setup_estimator(unsigned A, unsigned time_const, struct tc_estimator *est)
+{
+       for (est->interval=0; est->interval<=5; est->interval++) {
+               if (A <= (1<<est->interval)*(1000000/4))
+                       break;
+       }
+       if (est->interval > 5)
+               return -1;
+       est->interval -= 2;
+       for (est->ewma_log=1; est->ewma_log<32; est->ewma_log++) {
+               double w = 1.0 - 1.0/(1<<est->ewma_log);
+               if (A/(-log(w)) > time_const)
+                       break;
+       }
+       est->ewma_log--;
+       if (est->ewma_log==0 || est->ewma_log >= 31)
+               return -1;
+       return 0;
+}