Share the vtables with threaded perls

[perl/modules/Variable-Magic.git] / Magic.xs

diff --git a/Magic.xs b/Magic.xs
index 4ac45e73ec12e7de3d11e359d26b38742c2fc2a9..3fb9739614332542a19485443cc7d737c4a6fa50 100644 (file)
--- a/Magic.xs
+++ b/Magic.xs
@@ -431,10 +431,79 @@ STATIC const char vmg_argstorefailed[] = "Error while storing arguments";
 #define SIG_WZO ((U16) (0x3891))
 #define SIG_WIZ ((U16) (0x3892))
 
-/* --- MGWIZ structure ----------------------------------------------------- */
+/* --- <vmg_vtable> structure ---------------------------------------------- */
+
+#if VMG_THREADSAFE
 
 typedef struct {
  MGVTBL *vtbl;
+ U32     refcount;
+} vmg_vtable;
+
+STATIC vmg_vtable *vmg_vtable_alloc(pTHX) {
+#define vmg_vtable_alloc() vmg_vtable_alloc(aTHX)
+ vmg_vtable *t;
+
+ t = VOID2(vmg_vtable *, PerlMemShared_malloc(sizeof *t));
+
+ t->vtbl     = VOID2(MGVTBL *, PerlMemShared_malloc(sizeof *t->vtbl));
+ t->refcount = 1;
+
+ return t;
+}
+
+#define vmg_vtable_vtbl(T) (T)->vtbl
+
+#if VMG_THREADSAFE
+STATIC perl_mutex vmg_vtable_refcount_mutex;
+#endif
+
+STATIC vmg_vtable *vmg_vtable_dup(pTHX_ vmg_vtable *t) {
+#define vmg_vtable_dup(T) vmg_vtable_dup(aTHX_ (T))
+ VMG_LOCK(&vmg_vtable_refcount_mutex);
+ ++t->refcount;
+ VMG_UNLOCK(&vmg_vtable_refcount_mutex);
+
+ return t;
+}
+
+STATIC void vmg_vtable_free(pTHX_ vmg_vtable *t) {
+#define vmg_vtable_free(T) vmg_vtable_free(aTHX_ (T))
+ U32 refcount;
+
+ VMG_LOCK(&vmg_vtable_refcount_mutex);
+ refcount = --t->refcount;
+ VMG_UNLOCK(&vmg_vtable_refcount_mutex);
+
+ if (!refcount) {
+  PerlMemShared_free(t->vtbl);
+  PerlMemShared_free(t);
+ }
+}
+
+#else /* VMG_THREADSAFE */
+
+typedef MGVTBL vmg_vtable;
+
+STATIC vmg_vtable *vmg_vtable_alloc(pTHX) {
+#define vmg_vtable_alloc() vmg_vtable_alloc(aTHX)
+ vmg_vtable *t;
+
+ Newx(t, 1, vmg_vtable);
+
+ return t;
+}
+
+#define vmg_vtable_vtbl(T) ((MGVTBL *) (T))
+
+#define vmg_vtable_free(T) Safefree(T)
+
+#endif /* !VMG_THREADSAFE */
+
+/* --- MGWIZ structure ----------------------------------------------------- */
+
+typedef struct {
+ vmg_vtable *vtable;
 
  U8 opinfo;
  U8 uvar;
@@ -469,8 +538,7 @@ STATIC MGWIZ *vmg_mgwiz_alloc(pTHX_ UV opinfo) {
  if (w->opinfo)
   vmg_op_info_init(aTHX_ w->opinfo);
 
- Newx(t, 1, MGVTBL);
- w->vtbl = t;
+ w->vtable = vmg_vtable_alloc();
 
  return w;
 }
@@ -509,7 +577,7 @@ STATIC void vmg_mgwiz_free(pTHX_ MGWIZ *w) {
  SvREFCNT_dec(w->cb_delete);
 #endif /* VMG_UVAR */
 
- Safefree(w->vtbl);
+ vmg_vtable_free(w->vtable);
  Safefree(w);
 
  return;
@@ -523,18 +591,14 @@ STATIC void vmg_mgwiz_free(pTHX_ MGWIZ *w) {
 
 STATIC MGWIZ *vmg_mgwiz_clone(pTHX_ const MGWIZ *w) {
 #define vmg_mgwiz_clone(W) vmg_mgwiz_clone(aTHX_ (W))
- MGVTBL *t;
  MGWIZ *z;
 
  if (!w)
   return NULL;
 
- Newx(t, 1, MGVTBL);
- Copy(w->vtbl, t, 1, MGVTBL);
-
  Newx(z, 1, MGWIZ);
 
- z->vtbl   = t;
+ z->vtable = vmg_vtable_dup(w->vtable);
  z->uvar   = w->uvar;
  z->opinfo = w->opinfo;
 
@@ -799,7 +863,7 @@ STATIC UV vmg_cast(pTHX_ SV *sv, const SV *wiz, SV **args, I32 items) {
 
  data = (w->cb_data) ? vmg_data_new(w->cb_data, sv, args, items) : NULL;
  /* sv_magicext() calls mg_magical and increments data's refcount */
- mg   = sv_magicext(sv, data, PERL_MAGIC_ext, w->vtbl,
+ mg   = sv_magicext(sv, data, PERL_MAGIC_ext, vmg_vtable_vtbl(w->vtable),
                               (const char *) wiz, HEf_SVKEY);
  SvREFCNT_dec(data);
  mg->mg_private = SIG_WIZ;
@@ -1375,6 +1439,7 @@ BOOT:
 #endif
  MY_CXT.b__op_stashes[0] = NULL;
 #if VMG_THREADSAFE
+ MUTEX_INIT(&vmg_vtable_refcount_mutex);
  MUTEX_INIT(&vmg_op_name_init_mutex);
  call_atexit(vmg_cleanup, NULL);
 #endif
@@ -1459,7 +1524,7 @@ CODE:
 
  op_info = ST(i++);
  w = vmg_mgwiz_alloc(SvOK(op_info) ? SvUV(op_info) : 0);
- t = w->vtbl;
+ t = vmg_vtable_vtbl(w->vtable);
 
  VMG_SET_CB(ST(i++), data);