separate Thread type (func or proc) explicitly.

* vm_core.h (rb_thread_struct): introduce new fields `invoke_type`
  and `invoke_arg`.
  There are two types threads: invoking proc (normal Ruby thread
  created by `Thread.new do ... end`) and invoking func, created
  by C-API. `invoke_type` shows the types.

* thread.c (thread_do_start): copy `invoke_arg.proc.args` contents
  from Array to ALLOCA stack memory if args length is enough small (<8).
  We don't need to keep Array and don't need to cancel using transient heap.

* vm.c (thread_mark): For func invoking threads, they can pass (void *)
  parameter (rb_thread_t::invoke_arg::func::arg). However, a rubyspec test
  (thread_spec.c) passes an Array object and it expect to mark it.
  Clealy it is out of scope (misuse of `rb_thread_create` C-API). However,
  I'm not sure someone else has such kind of misunderstanding.
  So now we mark conservatively this (void *) arg with rb_gc_mark_maybe.

  This misuse is found by this error log.
  http://ci.rvm.jp/results/trunk-theap-asserts@silicon-docker/1448164


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65622 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 11 insertions, 2 deletions

diff --git a/vm.c b/vm.c
index 5f89cacd1c..2844441997 100644
--- a/vm.c
+++ b/vm.c
@@ -2435,8 +2435,17 @@ thread_mark(void *ptr)
     rb_fiber_mark_self(th->ec->fiber_ptr);
 
     /* mark ruby objects */
-    RUBY_MARK_UNLESS_NULL(th->first_proc);
-    if (th->first_proc) RUBY_MARK_UNLESS_NULL(th->first_args);
+    switch (th->invoke_type) {
+      case thread_invoke_type_proc:
+        RUBY_MARK_UNLESS_NULL(th->invoke_arg.proc.proc);
+        RUBY_MARK_UNLESS_NULL(th->invoke_arg.proc.args);
+        break;
+      case thread_invoke_type_func:
+        rb_gc_mark_maybe((VALUE)th->invoke_arg.func.arg);
+        break;
+      default:
+        break;
+    }
 
     RUBY_MARK_UNLESS_NULL(th->thgroup);
     RUBY_MARK_UNLESS_NULL(th->value);