diff options
| -rw-r--r-- | Include/objimpl.h | 12 | ||||
| -rw-r--r-- | Modules/gcmodule.c | 22 |
2 files changed, 26 insertions, 8 deletions
diff --git a/Include/objimpl.h b/Include/objimpl.h index e037322..28f3661 100644 --- a/Include/objimpl.h +++ b/Include/objimpl.h @@ -262,12 +262,18 @@ extern PyGC_Head *_PyGC_generation0; #define _Py_AS_GC(o) ((PyGC_Head *)(o)-1) +#define _PyGC_REFS_UNTRACKED (-2) +#define _PyGC_REFS_REACHABLE (-3) +#define _PyGC_REFS_TENTATIVELY_UNREACHABLE (-4) + /* Tell the GC to track this object. NB: While the object is tracked the * collector it must be safe to call the ob_traverse method. */ #define _PyObject_GC_TRACK(o) do { \ PyGC_Head *g = _Py_AS_GC(o); \ - if (g->gc.gc_next != NULL) \ - Py_FatalError("GC object already in linked list"); \ + if (g->gc.gc_refs != _PyGC_REFS_UNTRACKED) \ + Py_FatalError("GC object already tracked"); \ + assert(g->gc.gc_refs == _PyGC_REFS_UNTRACKED); \ + g->gc.gc_refs = _PyGC_REFS_REACHABLE; \ g->gc.gc_next = _PyGC_generation0; \ g->gc.gc_prev = _PyGC_generation0->gc.gc_prev; \ g->gc.gc_prev->gc.gc_next = g; \ @@ -277,6 +283,8 @@ extern PyGC_Head *_PyGC_generation0; /* Tell the GC to stop tracking this object. */ #define _PyObject_GC_UNTRACK(o) do { \ PyGC_Head *g = _Py_AS_GC(o); \ + assert(g->gc.gc_refs != _PyGC_REFS_UNTRACKED); \ + g->gc.gc_refs = _PyGC_REFS_UNTRACKED; \ g->gc.gc_prev->gc.gc_next = g->gc.gc_next; \ g->gc.gc_next->gc.gc_prev = g->gc.gc_prev; \ g->gc.gc_next = NULL; \ diff --git a/Modules/gcmodule.c b/Modules/gcmodule.c index cb56253..7148e4c 100644 --- a/Modules/gcmodule.c +++ b/Modules/gcmodule.c @@ -82,8 +82,9 @@ static int debug; */ /* Special gc_refs values. */ -#define GC_REACHABLE -123 -#define GC_TENTATIVELY_UNREACHABLE -42 +#define GC_UNTRACKED _PyGC_REFS_UNTRACKED +#define GC_REACHABLE _PyGC_REFS_REACHABLE +#define GC_TENTATIVELY_UNREACHABLE _PyGC_REFS_TENTATIVELY_UNREACHABLE #define IS_REACHABLE(o) ((AS_GC(o))->gc.gc_refs == GC_REACHABLE) #define IS_TENTATIVELY_UNREACHABLE(o) ( \ @@ -179,8 +180,10 @@ static void update_refs(PyGC_Head *containers) { PyGC_Head *gc = containers->gc.gc_next; - for (; gc != containers; gc = gc->gc.gc_next) + for (; gc != containers; gc = gc->gc.gc_next) { + assert(gc->gc.gc_refs == GC_REACHABLE); gc->gc.gc_refs = FROM_GC(gc)->ob_refcnt; + } } /* A traversal callback for subtract_refs. */ @@ -222,7 +225,7 @@ subtract_refs(PyGC_Head *containers) static int visit_reachable(PyObject *op, PyGC_Head *reachable) { - if (PyObject_IS_GC(op) && IS_TRACKED(op)) { + if (PyObject_IS_GC(op)) { PyGC_Head *gc = AS_GC(op); const int gc_refs = gc->gc.gc_refs; @@ -250,8 +253,14 @@ visit_reachable(PyObject *op, PyGC_Head *reachable) * list, and move_unreachable will eventually get to it. * If gc_refs == GC_REACHABLE, it's either in some other * generation so we don't care about it, or move_unreachable - * already dealt with it. + * already deat with it. + * If gc_refs == GC_UNTRACKED, it must be ignored. */ + else { + assert(gc_refs > 0 + || gc_refs == GC_REACHABLE + || gc_refs == GC_UNTRACKED); + } } return 0; } @@ -352,7 +361,7 @@ static int visit_move(PyObject *op, PyGC_Head *tolist) { if (PyObject_IS_GC(op)) { - if (IS_TRACKED(op) && IS_TENTATIVELY_UNREACHABLE(op)) { + if (IS_TENTATIVELY_UNREACHABLE(op)) { PyGC_Head *gc = AS_GC(op); gc_list_remove(gc); gc_list_append(gc, tolist); @@ -966,6 +975,7 @@ _PyObject_GC_Malloc(size_t basicsize) if (g == NULL) return PyErr_NoMemory(); g->gc.gc_next = NULL; + g->gc.gc_refs = GC_UNTRACKED; generations[0].count++; /* number of allocated GC objects */ if (generations[0].count > generations[0].threshold && enabled && |