Merge branch 'master' into measure-analysis

README.md

-#Packet Exchange repository
+# tsn-rt-measures repository
+
+clockres, latency-measure and packet-exchange are C programs wrote using
+the same structure as cyclictest, and borrows large portions of the cyclictest
+code:   
+
+They have a real-time thread doing measurements or time sensitive operations 
+at regular intervals, and a non real-time thread doing the I/O operations to
+report the results shared by the real-time thread.
+The real-time thread can be assigned to CPU1 (which I chose to isolate on the Olimex boards) and
+can have it's priority set as an option, default is to 99. It writes results in a static structure.
+
+* clockres is used to determine the resolution of the clock (CLOCK_MONOTONIC), by doing successive
+calls to clock_gettime
+* latency-measure is used to determine the maximum wakeup latency of a real-time thread. It is
+a simplified version of cyclictest I wrote to have a better understanding and more control.
+* packet-exchange has a client and a server, which exchange UDP ethernet packets using real-time threads,
+and can send them on a ETF qdisc by setting a txtime timestamp.
+* scripts contain useful bash scripts to be used on the boards

scripts/create_qdisc

+#!/bin/bash
+
+usage() {
+  echo "Usage: $0 -e delta|-p" 1>&2;
+  exit 1;
+}
+
+while getopts "e:p" opt; do
+  case "${opt}" in
+    e )
+        delta=${OPTARG}
+        use_etf=1
+        ;;
+    p )
+        use_pfast=1
+      ;;
+    * )
+        usage
+      ;;
+  esac
+done
+
+shift $((OPTIND-1))
+if [ -z "${use_etf}" ] && [ -z "${use_pfast}" ]; then
+  usage
+fi
+if [ -n "${use_etf}" ] && [ -n "${use_pfast}" ]; then
+  usage
+fi
+
+if [ -n "${use_etf}" ]; then
+  echo "Creating ETF qdisc with delta $delta"
+  tc qdisc del root dev eth0;
+  tc qdisc add dev eth0 parent root handle 100 prio bands 2 priomap 1 1 1 1 1 1 1 1 0 1 1 1 1 1 1 1;
+  tc qdisc add dev eth0 parent 100:1 etf clockid CLOCK_TAI delta $delta;
+  tc qdisc show dev eth0;
+elif [ -n "${use_pfast}" ]; then
+  echo "Creating pfast qdisc"
+  tc qdisc del root dev eth0;
+  tc qdisc show;
+fi