torture: Use numeric taskset argument in jitter.sh

The jitter.sh script has some entertaining awk code to generate a
hex mask from a randomly selected CPU number, which is handed to the
"taskset" command.  Except that this command has a "-c" parameter to
take a comma/dash-separated list of CPU numbers.  This commit therefore
saves a few lines of awk by switching to a single-number CPU list.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

diff --git a/tools/testing/selftests/rcutorture/bin/jitter.sh b/tools/testing/selftests/rcutorture/bin/jitter.sh
index 15d937b..fd1ffaa 100755 (executable)
--- a/tools/testing/selftests/rcutorture/bin/jitter.sh
+++ b/tools/testing/selftests/rcutorture/bin/jitter.sh
@@ -68,16 +68,12 @@ do
        cpumask=`awk -v cpus="$cpus" -v me=$me -v n=$n 'BEGIN {
                srand(n + me + systime());
                ncpus = split(cpus, ca);
-               curcpu = ca[int(rand() * ncpus + 1)];
-               z = "";
-               for (i = 1; 4 * i <= curcpu; i++)
-                       z = z "0";
-               print "0x" 2 ^ (curcpu % 4) z;
+               print ca[int(rand() * ncpus + 1)];
        }' < /dev/null`
        n=$(($n+1))
-       if ! taskset -p $cpumask $$ > /dev/null 2>&1
+       if ! taskset -c -p $cpumask $$ > /dev/null 2>&1
        then
-               echo taskset failure: '"taskset -p ' $cpumask $$ '"'
+               echo taskset failure: '"taskset -c -p ' $cpumask $$ '"'
                exit 1
        fi