testing/test_runner: Always mount new bpffs

Since we run in a separate mount namespace, we should always mount a new bpffs
during setup. This way, we are sure the bpffs instance will be removed once we
exit the test run, which ensures that no pinned programs are left at the end of
the test.

Signed-off-by: Toke Høiland-Jørgensen <[email protected]>

Author: tohojo

lib/testing/test_runner.sh

@@ -242,6 +242,8 @@ check_prereq()
     if [ "$max_locked_mem" != "unlimited" ]; then
 	ulimit -l unlimited || die "Unable to set ulimit"
     fi
+
+    mount -t bpf bpf /sys/fs/bpf/ || die "Unable to mount bpffs"
 }
 
 gen_nsname()
@@ -301,10 +303,6 @@ init_ns()
     OUTSIDE_IP6="${IP6_PREFIX}1"
     OUTSIDE_IP4="${IP4_PREFIX}1"
 
-    if ! mount | grep -q /sys/fs/bpf; then
-        mount -t bpf bpf /sys/fs/bpf/
-    fi
-
     ip netns add "$nsname"
     ip link add dev "$nsname" type veth peer name "$peername"
     set_sysctls $nsname