selftests/bpf: Bump internal send_signal/send_signal_tracepoint timeout

The send_signal/send_signal_tracepoint is pretty flaky, with at least
one failure in every ten runs on a few attempts I've tried it:
  > test_send_signal_common:PASS:pipe_c2p 0 nsec
  > test_send_signal_common:PASS:pipe_p2c 0 nsec
  > test_send_signal_common:PASS:fork 0 nsec
  > test_send_signal_common:PASS:skel_open_and_load 0 nsec
  > test_send_signal_common:PASS:skel_attach 0 nsec
  > test_send_signal_common:PASS:pipe_read 0 nsec
  > test_send_signal_common:PASS:pipe_write 0 nsec
  > test_send_signal_common:PASS:reading pipe 0 nsec
  > test_send_signal_common:PASS:reading pipe error: size 0 0 nsec
  > test_send_signal_common:FAIL:incorrect result unexpected incorrect result: actual 48 != expected 50
  > test_send_signal_common:PASS:pipe_write 0 nsec
  > #139/1   send_signal/send_signal_tracepoint:FAIL

The reason does not appear to be a correctness issue in the strict
sense. Rather, we merely do not receive the signal we are waiting for
within the provided timeout.
Let's bump the timeout by a factor of ten. With that change I have not
been able to reproduce the failure in 150+ iterations. I am also sneaking
in a small simplification to the test_progs test selection logic.
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220727182955.4044988-1-deso@posteo.net

tools/testing/selftests/bpf/prog_tests/send_signal.c

@@ -64,7 +64,7 @@ static void test_send_signal_common(struct perf_event_attr *attr,
 		ASSERT_EQ(read(pipe_p2c[0], buf, 1), 1, "pipe_read");
 
 		/* wait a little for signal handler */
-		for (int i = 0; i < 100000000 && !sigusr1_received; i++)
+		for (int i = 0; i < 1000000000 && !sigusr1_received; i++)
 			j /= i + j + 1;
 
 		buf[0] = sigusr1_received ? '2' : '0';

tools/testing/selftests/bpf/test_progs.c

@@ -1604,11 +1604,8 @@ int main(int argc, char **argv)
 		struct prog_test_def *test = &prog_test_defs[i];
 
 		test->test_num = i + 1;
-		if (should_run(&env.test_selector,
-				test->test_num, test->test_name))
-			test->should_run = true;
-		else
-			test->should_run = false;
+		test->should_run = should_run(&env.test_selector,
+					      test->test_num, test->test_name);
 
 		if ((test->run_test == NULL && test->run_serial_test == NULL) ||
 		    (test->run_test != NULL && test->run_serial_test != NULL)) {