selftests/user_events: Add non-spacing separator check

The ABI documentation indicates that field separators do not need a
space between them, only a ';'. When no spacing is used, the register
must work. Any subsequent register, with or without spaces, must match
and not return -EADDRINUSE.

Add a non-spacing separator case to our self-test register case to ensure
it works going forward.

Link: https://lore.kernel.org/linux-trace-kernel/20240423162338.292-3-beaub@linux.microsoft.com

Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

Author: beaubelgrave

tools/testing/selftests/user_events/ftrace_test.c

@@ -261,6 +261,12 @@ TEST_F(user, register_events) {
 	ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, &reg));
 	ASSERT_EQ(0, reg.write_index);
 
+	/* Register without separator spacing should still match */
+	reg.enable_bit = 29;
+	reg.name_args = (__u64)"__test_event u32 field1;u32 field2";
+	ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, &reg));
+	ASSERT_EQ(0, reg.write_index);
+
 	/* Multiple registers to same name but different args should fail */
 	reg.enable_bit = 29;
 	reg.name_args = (__u64)"__test_event u32 field1;";
@@ -288,6 +294,8 @@ TEST_F(user, register_events) {
 	ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSUNREG, &unreg));
 	unreg.disable_bit = 30;
 	ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSUNREG, &unreg));
+	unreg.disable_bit = 29;
+	ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSUNREG, &unreg));
 
 	/* Delete should have been auto-done after close and unregister */
 	close(self->data_fd);