mtr runs only "big" tests, if --big-test is repeated twice

mysql-test/lib/mtr_cases.pm

@@ -925,6 +925,13 @@ sub collect_one_test_case {
     return $tinfo
   }
 
+  if ( ! $tinfo->{'big_test'} and $::opt_big_test > 1 )
+  {
+    $tinfo->{'skip'}= 1;
+    $tinfo->{'comment'}= "Small test";
+    return $tinfo
+  }
+
   if ( $tinfo->{'need_debug'} && ! $::debug_compiled_binaries )
   {
     $tinfo->{'skip'}= 1;

mysql-test/mysql-test-run.pl

@@ -986,7 +986,7 @@ sub command_line_setup {
              'skip-test=s'              => \&collect_option,
              'do-test=s'                => \&collect_option,
              'start-from=s'             => \&collect_option,
-             'big-test'                 => \$opt_big_test,
+             'big-test+'                => \$opt_big_test,
 	     'combination=s'            => \@opt_combinations,
              'skip-combinations'        => \&collect_option,
              'experimental=s'           => \@opt_experimentals,
@@ -5984,7 +5984,8 @@ Options to control what test suites or cases to run
                         list of suite names.
                         The default is: "$DEFAULT_SUITES"
   skip-rpl              Skip the replication test cases.
-  big-test              Also run tests marked as "big"
+  big-test              Also run tests marked as "big". Repeat this option
+                        twice to run only "big" tests.
   staging-run           Run a limited number of tests (no slow tests). Used
                         for running staging trees with valgrind.
   enable-disabled       Run also tests marked as disabled