* thread.c (rb_barrier_waiting): save the number of waiting threads

in RBASIC()->flags. [ruby-dev:45002] [Bug #5768]

* thread.c (rb_barrier_wait): increment and decrement around
  rb_mutex_lock, and use rb_barrier_waiting().

* thread.c (rb_barrier_release): use rb_barrier_waiting().

* thread.c (rb_barrier_destroy): ditto.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@34163 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,15 @@
+Sat Dec 31 06:28:37 2011  NARUSE, Yui  <naruse@ruby-lang.org>
+
+	* thread.c (rb_barrier_waiting): save the number of waiting threads
+	  in RBASIC()->flags. [ruby-dev:45002] [Bug #5768]
+
+	* thread.c (rb_barrier_wait): increment and decrement around
+	  rb_mutex_lock, and use rb_barrier_waiting().
+
+	* thread.c (rb_barrier_release): use rb_barrier_waiting().
+
+	* thread.c (rb_barrier_destroy): ditto.
+
 Mon Dec 26 17:20:10 2011  NARUSE, Yui  <naruse@ruby-lang.org>
 
 	* vm.c (vm_exec): add guard to prevent optimization for LLVM clang.

internal.h

@@ -181,7 +181,6 @@ void rb_thread_execute_interrupts(VALUE th);
 void rb_clear_trace_func(void);
 VALUE rb_thread_backtrace(VALUE thval);
 VALUE rb_get_coverages(void);
-int rb_barrier_waiting(VALUE barrier);
 
 /* thread_pthread.c, thread_win32.c */
 void Init_native_thread(void);

thread.c

@@ -3685,6 +3685,21 @@ barrier_alloc(VALUE klass)
 }
 
 #define GetBarrierPtr(obj) ((VALUE)rb_check_typeddata((obj), &barrier_data_type))
+#define BARRIER_WAITING_MASK (FL_USER0|FL_USER1|FL_USER2|FL_USER3|FL_USER4|FL_USER5|FL_USER6|FL_USER7|FL_USER8|FL_USER9|FL_USER10|FL_USER11|FL_USER12|FL_USER13|FL_USER14|FL_USER15|FL_USER16|FL_USER17|FL_USER18|FL_USER19)
+#define BARRIER_WAITING_SHIFT (FL_USHIFT)
+#define rb_barrier_waiting(b) ((RBASIC(b)->flags&BARRIER_WAITING_MASK)>>BARRIER_WAITING_SHIFT)
+#define rb_barrier_waiting_inc(b) do { \
+    int w = rb_barrier_waiting(b); \
+    w++; \
+    RBASIC(b)->flags &= ~BARRIER_WAITING_MASK; \
+    RBASIC(b)->flags |= (w << BARRIER_WAITING_SHIFT); \
+} while (0)
+#define rb_barrier_waiting_dec(b) do { \
+    int w = rb_barrier_waiting(b); \
+    w--; \
+    RBASIC(b)->flags &= ~BARRIER_WAITING_MASK; \
+    RBASIC(b)->flags |= (w << BARRIER_WAITING_SHIFT); \
+} while (0)
 
 VALUE
 rb_barrier_new(void)
@@ -3707,16 +3722,16 @@ rb_barrier_wait(VALUE self)
 {
     VALUE mutex = GetBarrierPtr(self);
     rb_mutex_t *m;
-    int waiting;
 
     if (!mutex) return Qfalse;
     GetMutexPtr(mutex, m);
     if (m->th == GET_THREAD()) return Qnil;
+    rb_barrier_waiting_inc(self);
     rb_mutex_lock(mutex);
+    rb_barrier_waiting_dec(self);
     if (DATA_PTR(self)) return Qtrue;
-    waiting = m->cond_waiting;
     rb_mutex_unlock(mutex);
-    return waiting ? Qnil : Qfalse;
+    return rb_barrier_waiting(self) > 0 ? Qnil : Qfalse;
 }
 
 /*
@@ -3726,10 +3741,8 @@ VALUE
 rb_barrier_release(VALUE self)
 {
     VALUE mutex = GetBarrierPtr(self);
-    rb_mutex_t *m;
     rb_mutex_unlock(mutex);
-    GetMutexPtr(mutex, m);
-    return m->cond_waiting > 0 ? Qtrue : Qfalse;
+    return rb_barrier_waiting(self) > 0 ? Qtrue : Qfalse;
 }
 
 /*
@@ -3739,22 +3752,9 @@ VALUE
 rb_barrier_destroy(VALUE self)
 {
     VALUE mutex = GetBarrierPtr(self);
-    rb_mutex_t *m;
     DATA_PTR(self) = 0;
     rb_mutex_unlock(mutex);
-    GetMutexPtr(mutex, m);
-    return m->cond_waiting > 0 ? Qtrue : Qfalse;
-}
-
-int
-rb_barrier_waiting(VALUE self)
-{
-    VALUE mutex = GetBarrierPtr(self);
-    rb_mutex_t *m;
-
-    if (!mutex) return 0;
-    GetMutexPtr(mutex, m);
-    return m->cond_waiting;
+    return rb_barrier_waiting(self) > 0 ? Qtrue : Qfalse;
 }
 
 /* variables for recursive traversals */