kselftest/runner.sh: add netns support

Add a variable RUN_IN_NETNS if the user wants to run all the selected tests
in namespace in parallel. With this, we can save a lot of testing time.

Note that some tests may not fit to run in namespace, e.g.
net/drop_monitor_tests.sh, as the dwdump needs to be run in init ns.

I also added another parameter -p to make all the logs reported separately
instead of mixing them in the stdout or output.log.

Nit: the NUM in run_one is not used, rename it to test_num.
Acked-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/kselftest/runner.sh

@@ -6,6 +6,7 @@ export skip_rc=4
 export timeout_rc=124
 export logfile=/dev/stdout
 export per_test_logging=
+export RUN_IN_NETNS=
 
 # Defaults for "settings" file fields:
 # "timeout" how many seconds to let each test run before running
@@ -47,7 +48,7 @@ run_one()
 {
 	DIR="$1"
 	TEST="$2"
-	NUM="$3"
+	local test_num="$3"
 
 	BASENAME_TEST=$(basename $TEST)
 
@@ -141,6 +142,33 @@ run_one()
 	fi
 }
 
+in_netns()
+{
+	local name=$1
+	ip netns exec $name bash <<-EOF
+		BASE_DIR=$BASE_DIR
+		source $BASE_DIR/kselftest/runner.sh
+		logfile=$logfile
+		run_one $DIR $TEST $test_num
+	EOF
+}
+
+run_in_netns()
+{
+	local netns=$(mktemp -u ${BASENAME_TEST}-XXXXXX)
+	local tmplog="/tmp/$(mktemp -u ${BASENAME_TEST}-XXXXXX)"
+	ip netns add $netns
+	if [ $? -ne 0 ]; then
+		echo "# Warning: Create namespace failed for $BASENAME_TEST"
+		echo "not ok $test_num selftests: $DIR: $BASENAME_TEST # Create NS failed"
+	fi
+	ip -n $netns link set lo up
+	in_netns $netns &> $tmplog
+	ip netns del $netns &> /dev/null
+	cat $tmplog
+	rm -f $tmplog
+}
+
 run_many()
 {
 	echo "TAP version 13"
@@ -155,6 +183,12 @@ run_many()
 			logfile="/tmp/$BASENAME_TEST"
 			cat /dev/null > "$logfile"
 		fi
-		run_one "$DIR" "$TEST" "$test_num"
+		if [ -n "$RUN_IN_NETNS" ]; then
+			run_in_netns &
+		else
+			run_one "$DIR" "$TEST" "$test_num"
+		fi
 	done
+
+	wait
 }

tools/testing/selftests/run_kselftest.sh

@@ -20,11 +20,13 @@ usage()
 {
 	cat <<EOF
 Usage: $0 [OPTIONS]
-  -s | --summary		Print summary with detailed log in output.log
+  -s | --summary		Print summary with detailed log in output.log (conflict with -p)
+  -p | --per_test_log		Print test log in /tmp with each test name (conflict with -s)
   -t | --test COLLECTION:TEST	Run TEST from COLLECTION
   -c | --collection COLLECTION	Run all tests from COLLECTION
   -l | --list			List the available collection:test entries
   -d | --dry-run		Don't actually run any tests
+  -n | --netns			Run each test in namespace
   -h | --help			Show this usage info
   -o | --override-timeout	Number of seconds after which we timeout
 EOF
@@ -41,6 +43,9 @@ while true; do
 			logfile="$BASE_DIR"/output.log
 			cat /dev/null > $logfile
 			shift ;;
+		-p | --per-test-log)
+			per_test_logging=1
+			shift ;;
 		-t | --test)
 			TESTS="$TESTS $2"
 			shift 2 ;;
@@ -53,6 +58,9 @@ while true; do
 		-d | --dry-run)
 			dryrun="echo"
 			shift ;;
+		-n | --netns)
+			RUN_IN_NETNS=1
+			shift ;;
 		-o | --override-timeout)
 			kselftest_override_timeout="$2"
 			shift 2 ;;