merges r32345 from trunk into ruby_1_9_2.

--
* thread.c (rb_threadptr_check_signal): only wake up main thread.
* thread.c (rb_threadptr_execute_interrupts_common): check signal
  deliverly if it is main thread.
  fixes [ruby-dev:44005] [Ruby 1.9 - Bug #4950]
* bootstraptest/test_fork.rb: add a test for above.
* signal.c (rb_get_next_signal): skip if signal_buff is empty.
  (check signal_buff.size first)
* vm_core.h: remove unused variable rb_thread_t::exec_signal.
* thread.c (rb_thread_check_trap_pending): check
  rb_signal_buff_size() because rb_thread_t::exec_signal
  is no longer available.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_2@32926 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 8 insertions, 19 deletions

diff --git a/thread.c b/thread.c
index 10da7fff02..f8be654e6a 100644
--- a/thread.c
+++ b/thread.c
@@ -985,7 +985,7 @@ rb_thread_check_ints(void)
 int
 rb_thread_check_trap_pending(void)
 {
-    return GET_THREAD()->exec_signal != 0;
+    return rb_signal_buff_size() != 0;
 }
 
 /* This function can be called in blocking region. */
@@ -1252,25 +1252,22 @@ thread_s_pass(VALUE klass)
 static void
 rb_threadptr_execute_interrupts_rec(rb_thread_t *th, int sched_depth)
 {
-    if (GET_VM()->main_thread == th) {
-	while (rb_signal_buff_size() && !th->exec_signal) native_thread_yield();
-    }
-
     if (th->raised_flag) return;
 
     while (th->interrupt_flag) {
 	enum rb_thread_status status = th->status;
 	int timer_interrupt = th->interrupt_flag & 0x01;
 	int finalizer_interrupt = th->interrupt_flag & 0x04;
+        int sig;
 
 	th->status = THREAD_RUNNABLE;
 	th->interrupt_flag = 0;
 
 	/* signal handling */
-	if (th->exec_signal) {
-	    int sig = th->exec_signal;
-	    th->exec_signal = 0;
-	    rb_signal_exec(th, sig);
+	if (th == th->vm->main_thread) {
+	    while ((sig = rb_get_next_signal()) != 0) {
+		rb_signal_exec(th, sig);
+	    }
 	}
 
 	/* exception from another thread */
@@ -2664,18 +2661,10 @@ int rb_get_next_signal(void);
 void
 rb_threadptr_check_signal(rb_thread_t *mth)
 {
-    int sig;
-
     /* mth must be main_thread */
-
-    if (!mth->exec_signal && (sig = rb_get_next_signal()) > 0) {
-	enum rb_thread_status prev_status = mth->status;
-	thread_debug("main_thread: %s, sig: %d\n",
-		     thread_status_name(prev_status), sig);
-	mth->exec_signal = sig;
-	if (mth->status != THREAD_KILLED) mth->status = THREAD_RUNNABLE;
+    if (rb_signal_buff_size() > 0) {
+	/* wakeup main thread */
 	rb_threadptr_interrupt(mth);
-	mth->status = prev_status;
     }
 }