merge revision(s) 33361,33460: [Backport #9463]

	* gc.c (slot_sweep, rb_gc_finalize_deferred)
	  (rb_objspace_call_finalizer, rb_gc): run finalizers
	  sequencially.  [ruby-dev:44562]

	* gc.c (rb_gc_finalize_deferred, rb_objspace_call_finalizer):
	  should use ATOMIC_EXCHANGE() to check the previous value.
	  [ruby-dev:44596] [Bug #5439]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_3@44762 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 11 insertions, 3 deletions

diff --git a/gc.c b/gc.c
index 0f84e22966..c32a189dcc 100644
--- a/gc.c
+++ b/gc.c
@@ -377,6 +377,7 @@ typedef struct rb_objspace {
 	int dont_gc;
 	int dont_lazy_sweep;
 	int during_gc;
+	rb_atomic_t finalizing;
     } flags;
     struct {
 	st_table *table;
@@ -415,6 +416,7 @@ int *ruby_initial_gc_stress_ptr = &rb_objspace.gc_stress;
 #define heaps_freed		objspace->heap.freed
 #define dont_gc 		objspace->flags.dont_gc
 #define during_gc		objspace->flags.during_gc
+#define finalizing		objspace->flags.finalizing
 #define finalizer_table 	objspace->final.table
 #define deferred_final_list	objspace->final.deferred
 #define global_List		objspace->global_list
@@ -2175,7 +2177,7 @@ slot_sweep(rb_objspace_t *objspace, struct heaps_slot *sweep_slot)
     }
     objspace->heap.final_num += final_num;
 
-    if (deferred_final_list) {
+    if (deferred_final_list && !finalizing) {
         rb_thread_t *th = GET_THREAD();
         if (th) {
             RUBY_VM_SET_FINALIZER_INTERRUPT(th);
@@ -3053,7 +3055,10 @@ finalize_deferred(rb_objspace_t *objspace)
 void
 rb_gc_finalize_deferred(void)
 {
-    finalize_deferred(&rb_objspace);
+    rb_objspace_t *objspace = &rb_objspace;
+    if (ATOMIC_EXCHANGE(finalizing, 1)) return;
+    finalize_deferred(objspace);
+    ATOMIC_SET(finalizing, 0);
 }
 
 struct force_finalize_list {
@@ -3093,6 +3098,8 @@ rb_objspace_call_finalizer(rb_objspace_t *objspace)
     finalize_deferred(objspace);
     assert(deferred_final_list == 0);
 
+    if (ATOMIC_EXCHANGE(finalizing, 1)) return;
+
     /* force to run finalizer */
     while (finalizer_table->num_entries) {
 	struct force_finalize_list *list = 0;
@@ -3147,6 +3154,7 @@ rb_objspace_call_finalizer(rb_objspace_t *objspace)
 
     st_free_table(finalizer_table);
     finalizer_table = 0;
+    ATOMIC_SET(finalizing, 0);
 }
 
 void
@@ -3154,7 +3162,7 @@ rb_gc(void)
 {
     rb_objspace_t *objspace = &rb_objspace;
     garbage_collect(objspace);
-    finalize_deferred(objspace);
+    if (!finalizing) finalize_deferred(objspace);
     free_unused_heaps(objspace);
 }