Revert "[perl #117855] Store CopFILEGV in a pad under ithreads"

This reverts commit c82ecf3.

It turn out to be faulty, because a location shared betweens threads
(the cop) was holding a reference count on a pad entry in a particu-
lar thread.  So when you free the cop, how do you know where to do
SvREFCNT_dec?

In reverting c82ecf3, this commit still preserves the bug fix from
1311cfc, but shifts it around.

Author: Father Chrysostomos

MANIFEST

@@ -3870,7 +3870,7 @@ ext/XS-APItest/t/cleanup.t	test stack behaviour on unwinding
 ext/XS-APItest/t/clone-with-stack.t	test clone with CLONEf_COPY_STACKS works
 ext/XS-APItest/t/cophh.t	test COPHH API
 ext/XS-APItest/t/coplabel.t	test cop_*_label
-ext/XS-APItest/t/cop.t		test other cop stuff
+ext/XS-APItest/t/copstash.t	test alloccopstash
 ext/XS-APItest/t/copyhints.t	test hv_copy_hints_hv() API
 ext/XS-APItest/t/customop.t	XS::APItest: tests for custom ops
 ext/XS-APItest/t/eval-filter.t	Simple source filter/eval test

cop.h

@@ -389,8 +389,7 @@ struct cop {
 #ifdef USE_ITHREADS
     PADOFFSET	cop_stashoff;	/* offset into PL_stashpad, for the
 				   package the line was compiled in */
-    PADOFFSET	cop_filegvoff;	/* PL_filegv offset, for the file name the
-				   following line # is from */
+    char *	cop_file;	/* file name the following line # is from */
 #else
     HV *	cop_stash;	/* package line was compiled in */
     GV *	cop_filegv;	/* file the following line # is from */
@@ -405,32 +404,54 @@ struct cop {
 };
 
 #ifdef USE_ITHREADS
-#  define CopFILEGV(c)		PL_filegvpad[(c)->cop_filegvoff]
-#  define CopFILEGV_set(c,gv)	((c)->cop_filegvoff = (gv) \
-				 ? allocfilegv((GV *)SvREFCNT_inc_NN(gv)) \
-				 : 0)
+#  define CopFILE(c)		((c)->cop_file)
+#  define CopFILEGV(c)		(CopFILE(c) \
+				 ? gv_fetchfile(CopFILE(c)) : NULL)
+				 
+#  ifdef NETWARE
+#    define CopFILE_set(c,pv)	((c)->cop_file = savepv(pv))
+#    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savepv((pv),(l)))
+#  else
+#    define CopFILE_set(c,pv)	((c)->cop_file = savesharedpv(pv))
+#    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savesharedpvn((pv),(l)))
+#  endif
+
+#  define CopFILESV(c)		(CopFILE(c) \
+				 ? GvSV(gv_fetchfile(CopFILE(c))) : NULL)
+#  define CopFILEAV(c)		(CopFILE(c) \
+				 ? GvAV(gv_fetchfile(CopFILE(c))) : NULL)
+#  define CopFILEAVx(c)		(assert_(CopFILE(c)) \
+				   GvAV(gv_fetchfile(CopFILE(c))))
 
 #  define CopSTASH(c)           PL_stashpad[(c)->cop_stashoff]
 #  define CopSTASH_set(c,hv)	((c)->cop_stashoff = (hv)		\
 				    ? alloccopstash(hv)			\
 				    : 0)
-#  define CopFILE_free(c)	S_CopFILE_free(aTHX_ c)
+#  ifdef NETWARE
+#    define CopFILE_free(c) SAVECOPFILE_FREE(c)
+#  else
+#    define CopFILE_free(c)	(PerlMemShared_free(CopFILE(c)),(CopFILE(c) = NULL))
+#  endif
 #else
 #  define CopFILEGV(c)		((c)->cop_filegv)
 #  define CopFILEGV_set(c,gv)	((c)->cop_filegv = (GV*)SvREFCNT_inc(gv))
+#  define CopFILE_set(c,pv)	CopFILEGV_set((c), gv_fetchfile(pv))
+#  define CopFILE_setn(c,pv,l)	CopFILEGV_set((c), gv_fetchfile_flags((pv),(l),0))
+#  define CopFILESV(c)		(CopFILEGV(c) ? GvSV(CopFILEGV(c)) : NULL)
+#  define CopFILEAV(c)		(CopFILEGV(c) ? GvAV(CopFILEGV(c)) : NULL)
+#  ifdef DEBUGGING
+#    define CopFILEAVx(c)	(assert(CopFILEGV(c)), GvAV(CopFILEGV(c)))
+#  else
+#    define CopFILEAVx(c)	(GvAV(CopFILEGV(c)))
+# endif
+#  define CopFILE(c)		(CopFILEGV(c) \
+				    ? GvNAME(CopFILEGV(c))+2 : NULL)
 #  define CopSTASH(c)		((c)->cop_stash)
 #  define CopSTASH_set(c,hv)	((c)->cop_stash = (hv))
 #  define CopFILE_free(c)	(SvREFCNT_dec(CopFILEGV(c)),(CopFILEGV(c) = NULL))
 
 #endif /* USE_ITHREADS */
 
-#define CopFILE_set(c,pv)	CopFILEGV_set((c), gv_fetchfile(pv))
-#define CopFILE_setn(c,pv,l)	CopFILEGV_set((c), gv_fetchfile_flags((pv),(l),0))
-#define CopFILESV(c)		(CopFILEGV(c) ? GvSV(CopFILEGV(c)) : NULL)
-#define CopFILEAV(c)		(CopFILEGV(c) ? GvAV(CopFILEGV(c)) : NULL)
-#define CopFILEAVx(c)		(assert_(CopFILEGV(c)) GvAV(CopFILEGV(c)))
-#define CopFILE(c)		(CopFILEGV(c) \
-				    ? GvNAME(CopFILEGV(c))+2 : NULL)
 #define CopSTASHPV(c)		(CopSTASH(c) ? HvNAME_get(CopSTASH(c)) : NULL)
    /* cop_stash is not refcounted */
 #define CopSTASHPV_set(c,pv)	CopSTASH_set((c), gv_stashpv(pv,GV_ADD))

embed.fnc

@@ -1024,7 +1024,6 @@ p	|PADOFFSET|allocmy	|NN const char *const name|const STRLEN len\
 				|const U32 flags
 #ifdef USE_ITHREADS
 AMp	|PADOFFSET|alloccopstash|NN HV *hv
-AMp	|PADOFFSET|allocfilegv	|NN GV *gv
 #endif
 : Used in perly.y
 pR	|OP*	|oopsAV		|NN OP* o
@@ -2660,8 +2659,4 @@ op	|void	|populate_isa	|NN const char *name|STRLEN len|...
 Xop	|bool	|feature_is_enabled|NN const char *const name \
 		|STRLEN namelen
 
-: Some static inline functions that implement macros need predeclaration
-: because they are used inside other static inline functions.
-Aoi	|void	|SvREFCNT_dec_NN|NN SV *sv
-
 : ex: set ts=8 sts=4 sw=4 noet:

embed.h

@@ -806,7 +806,6 @@
 #endif
 #if defined(USE_ITHREADS)
 #define alloccopstash(a)	Perl_alloccopstash(aTHX_ a)
-#define allocfilegv(a)		Perl_allocfilegv(aTHX_ a)
 #define any_dup(a,b)		Perl_any_dup(aTHX_ a,b)
 #define cx_dup(a,b,c,d)		Perl_cx_dup(aTHX_ a,b,c,d)
 #define dirp_dup(a,b)		Perl_dirp_dup(aTHX_ a,b)

embedvar.h

@@ -146,9 +146,6 @@
 #define PL_exitlist		(vTHX->Iexitlist)
 #define PL_exitlistlen		(vTHX->Iexitlistlen)
 #define PL_fdpid		(vTHX->Ifdpid)
-#define PL_filegvpad		(vTHX->Ifilegvpad)
-#define PL_filegvpadix		(vTHX->Ifilegvpadix)
-#define PL_filegvpadmax		(vTHX->Ifilegvpadmax)
 #define PL_filemode		(vTHX->Ifilemode)
 #define PL_firstgv		(vTHX->Ifirstgv)
 #define PL_forkprocess		(vTHX->Iforkprocess)

ext/B/B.pm

@@ -1228,8 +1228,6 @@ Since perl 5.17.1
 
 =item file
 
-=item filegvoff (threaded only)
-
 =item cop_seq
 
 =item arybase

ext/B/B.xs

@@ -682,11 +682,7 @@ struct OP_methods {
 #ifdef USE_ITHREADS
     STR_WITH_LEN("pmoffset"),IVp,     offsetof(struct pmop, op_pmoffset),/*20*/
     STR_WITH_LEN("filegv"),  op_offset_special, 0,                       /*21*/
-#  if PERL_VERSION < 19
     STR_WITH_LEN("file"),    char_pp, offsetof(struct cop, cop_file),    /*22*/
-#  else
-    STR_WITH_LEN("file"),    op_offset_special, 0,                       /*22*/
-#  endif
     STR_WITH_LEN("stash"),   op_offset_special, 0,                       /*23*/
 #  if PERL_VERSION < 17
     STR_WITH_LEN("stashpv"), char_pp, offsetof(struct cop, cop_stashpv), /*24*/
@@ -732,11 +728,6 @@ struct OP_methods {
     STR_WITH_LEN("folded"),  op_offset_special, 0,                       /*50*/
 #endif
 #endif
-#if PERL_VERSION < 19 || !defined(USE_ITHREADS)
-    STR_WITH_LEN("filegvoff"),op_offset_special, 0,                      /*51*/
-#else
-    STR_WITH_LEN("filegvoff"),PADOFFSETp,offsetof(struct cop, cop_filegvoff),/*51*/
-#endif
 };
 
 #include "const-c.inc"
@@ -1040,7 +1031,7 @@ next(o)
 		ret = make_sv_object(aTHX_ (SV *)CopFILEGV((COP*)o));
 		break;
 #endif
-#if !defined(USE_ITHREADS) || PERL_VERSION >= 19
+#ifndef USE_ITHREADS
 	    case 22: /* file */
 		ret = sv_2mortal(newSVpv(CopFILE((COP*)o), 0));
 		break;

ext/XS-APItest/APItest.xs

@@ -3387,13 +3387,6 @@ CODE:
 OUTPUT:
     RETVAL
 
-bool
-test_allocfilegv()
-CODE:
-    RETVAL = PL_filegvpad[allocfilegv(PL_defgv)] == PL_defgv;
-OUTPUT:
-    RETVAL
-
 #endif
 
 bool

ext/XS-APItest/t/cop.t renamed to ext/XS-APItest/t/copstash.t

@@ -2,9 +2,8 @@ use Config;
 use Test::More;
 BEGIN { plan skip_all => 'no threads' unless $Config{useithreads} }
 
-plan tests => 2;
+plan tests => 1;
 
 use XS::APItest;
 
 ok test_alloccopstash;
-ok test_allocfilegv;

gv.c

@@ -2105,9 +2105,12 @@ Perl_gv_check(pTHX_ HV *stash)
 		    continue;
 		file = GvFILE(gv);
 		CopLINE_set(PL_curcop, GvLINE(gv));
-		/* set file name for warning */
-		CopFILE_setn(PL_curcop, file, HEK_LEN(GvFILE_HEK(gv)));
-		SvREFCNT_dec(CopFILEGV(PL_curcop));
+#ifdef USE_ITHREADS
+		CopFILE(PL_curcop) = (char *)file;	/* set for warning */
+#else
+		CopFILEGV(PL_curcop)
+		    = gv_fetchfile_flags(file, HEK_LEN(GvFILE_HEK(gv)), 0);
+#endif
 		Perl_warner(aTHX_ packWARN(WARN_ONCE),
 			"Name \"%"HEKf"::%"HEKf
 			"\" used only once: possible typo",

inline.h

@@ -23,20 +23,6 @@ S_av_top_index(pTHX_ AV *av)
     return AvFILL(av);
 }
 
-/* ------------------------------- cop.h ------------------------------ */
-
-#ifdef USE_ITHREADS
-PERL_STATIC_INLINE void
-S_CopFILE_free(pTHX_ COP * const c)
-{
-    GV * const gv = CopFILEGV(c);
-    if (!gv) return;
-    if (SvREFCNT(gv) == 1) PL_filegvpad[c->cop_filegvoff] = NULL;
-    SvREFCNT_dec_NN(gv);
-    c->cop_filegvoff = 0;
-}
-#endif
-
 /* ------------------------------- cv.h ------------------------------- */
 
 PERL_STATIC_INLINE I32 *
@@ -122,7 +108,6 @@ PERL_STATIC_INLINE void
 S_SvREFCNT_dec_NN(pTHX_ SV *sv)
 {
     U32 rc = SvREFCNT(sv);
-    PERL_ARGS_ASSERT_SVREFCNT_DEC_NN;
     if (LIKELY(rc > 1))
 	SvREFCNT(sv) = rc - 1;
     else

intrpvar.h

@@ -657,9 +657,6 @@ PERLVAR(I, regex_padav,   AV *)		/* All regex objects, indexed via the
 PERLVAR(I, stashpad,    HV **)		/* for CopSTASH */
 PERLVARI(I, stashpadmax, PADOFFSET, 64)
 PERLVARI(I, stashpadix, PADOFFSET, 0)
-PERLVAR(I, filegvpad,    GV **)		/* for CopFILEGV */
-PERLVARI(I, filegvpadmax, PADOFFSET, 64)
-PERLVARI(I, filegvpadix, PADOFFSET, 0)
 #endif
 
 #ifdef USE_REENTRANT_API

makedef.pl

@@ -363,9 +363,6 @@ sub readvar {
 		    PL_stashpad
 		    PL_stashpadix
 		    PL_stashpadmax
-		    PL_filegvpad
-		    PL_filegvpadix
-		    PL_filegvpadmax
 		    Perl_alloccopstash
 		    Perl_allocfilegv
 		    Perl_clone_params_del

op.c

@@ -634,64 +634,31 @@ C<PL_stashpad> for the stash passed to it.
 */
 
 #ifdef USE_ITHREADS
-
 PADOFFSET
-S_alloc_global_pad_slot(pTHX_ SV *sv, svtype type, SV ***padp,
-			      PADOFFSET *ixp, PADOFFSET *maxp)
+Perl_alloccopstash(pTHX_ HV *hv)
 {
     PADOFFSET off = 0, o = 1;
     bool found_slot = FALSE;
-    SV **pad = *padp;
 
-    if (pad[*ixp] == sv) return *ixp;
+    PERL_ARGS_ASSERT_ALLOCCOPSTASH;
+
+    if (PL_stashpad[PL_stashpadix] == hv) return PL_stashpadix;
 
-    for (; o < *maxp; ++o) {
-	if (pad[o] == sv) return *ixp = o;
-	if (!pad[o] || SvTYPE(pad[o]) != type)
+    for (; o < PL_stashpadmax; ++o) {
+	if (PL_stashpad[o] == hv) return PL_stashpadix = o;
+	if (!PL_stashpad[o] || SvTYPE(PL_stashpad[o]) != SVt_PVHV)
 	    found_slot = TRUE, off = o;
     }
     if (!found_slot) {
-	Renew(*padp, *maxp + 10, SV *);
-	pad = *padp;
-	Zero(pad + *maxp, 10, SV *);
-	off = *maxp;
-	*maxp += 10;
+	Renew(PL_stashpad, PL_stashpadmax + 10, HV *);
+	Zero(PL_stashpad + PL_stashpadmax, 10, HV *);
+	off = PL_stashpadmax;
+	PL_stashpadmax += 10;
     }
 
-    pad[*ixp = off] = sv;
+    PL_stashpad[PL_stashpadix = off] = hv;
     return off;
 }
-
-PADOFFSET
-Perl_alloccopstash(pTHX_ HV *hv)
-{
-    PERL_ARGS_ASSERT_ALLOCCOPSTASH;
-    return S_alloc_global_pad_slot(aTHX_
-		(SV *)hv, SVt_PVHV, (SV ***)&PL_stashpad, &PL_stashpadix,
-		&PL_stashpadmax
-	   );
-}
-#endif
-
-/*
-=for apidoc allocfilegv
-
-Available only under threaded builds, this function allocates an entry in
-C<PL_filegvpad> for the GV passed to it.
-
-=cut
-*/
-
-#ifdef USE_ITHREADS
-PADOFFSET
-Perl_allocfilegv(pTHX_ GV *gv)
-{
-    PERL_ARGS_ASSERT_ALLOCFILEGV;
-    return S_alloc_global_pad_slot(aTHX_
-		(SV *)gv, SVt_PVGV, (SV ***)&PL_filegvpad, &PL_filegvpadix,
-		&PL_filegvpadmax
-	   );
-}
 #endif
 
 /* free the body of an op without examining its contents.
@@ -5752,10 +5719,7 @@ Perl_newSTATEOP(pTHX_ I32 flags, char *label, OP *o)
 	PL_parser->copline = NOLINE;
     }
 #ifdef USE_ITHREADS
-    /* While CopFILEGV_set does work under ithreads, this is faster, as it
-       avoids a linear scan of the filegv pad: */
-    if((cop->cop_filegvoff = PL_curcop->cop_filegvoff))
-	SvREFCNT_inc_void_NN(PL_filegvpad[cop->cop_filegvoff]);
+    CopFILE_set(cop, CopFILE(PL_curcop));	/* XXX share in a pvtable? */
 #else
     CopFILEGV_set(cop, CopFILEGV(PL_curcop));
 #endif
@@ -10898,7 +10862,7 @@ Perl_rpeep(pTHX_ OP *o)
 		    firstcop->cop_line = secondcop->cop_line;
 #ifdef USE_ITHREADS
 		    firstcop->cop_stashoff = secondcop->cop_stashoff;
-		    firstcop->cop_filegvoff = secondcop->cop_filegvoff;
+		    firstcop->cop_file = secondcop->cop_file;
 #else
 		    firstcop->cop_stash = secondcop->cop_stash;
 		    firstcop->cop_filegv = secondcop->cop_filegv;
@@ -10910,7 +10874,7 @@ Perl_rpeep(pTHX_ OP *o)
 
 #ifdef USE_ITHREADS
 		    secondcop->cop_stashoff = 0;
-		    secondcop->cop_filegvoff = 0;
+		    secondcop->cop_file = NULL;
 #else
 		    secondcop->cop_stash = NULL;
 		    secondcop->cop_filegv = NULL;

perl.c

@@ -286,7 +286,6 @@ perl_construct(pTHXx)
     Perl_av_create_and_push(aTHX_ &PL_regex_padav, newSVpvs(""));
     PL_regex_pad = AvARRAY(PL_regex_padav);
     Newxz(PL_stashpad, PL_stashpadmax, HV *);
-    Newxz(PL_filegvpad, PL_filegvpadmax, GV *);
 #endif
 #ifdef USE_REENTRANT_API
     Perl_reentrant_init(aTHX);
@@ -1093,7 +1092,6 @@ perl_destruct(pTHXx)
 
 #ifdef USE_ITHREADS
     Safefree(PL_stashpad); /* must come after sv_clean_all */
-    Safefree(PL_filegvpad);
 #endif
 
     AvREAL_off(PL_fdpid);		/* no surviving entries */

proto.h

@@ -32,11 +32,6 @@ PERL_CALLCONV void	Perl_Slab_Free(pTHX_ void *op)
 #define PERL_ARGS_ASSERT_SLAB_FREE	\
 	assert(op)
 
-PERL_STATIC_INLINE void	S_SvREFCNT_dec_NN(pTHX_ SV *sv)
-			__attribute__nonnull__(pTHX_1);
-#define PERL_ARGS_ASSERT_SVREFCNT_DEC_NN	\
-	assert(sv)
-
 PERL_CALLCONV bool	Perl__is_uni_FOO(pTHX_ const U8 classnum, const UV c)
 			__attribute__warn_unused_result__;
 
@@ -7651,11 +7646,6 @@ PERL_CALLCONV PADOFFSET	Perl_alloccopstash(pTHX_ HV *hv)
 #define PERL_ARGS_ASSERT_ALLOCCOPSTASH	\
 	assert(hv)
 
-PERL_CALLCONV PADOFFSET	Perl_allocfilegv(pTHX_ GV *gv)
-			__attribute__nonnull__(pTHX_1);
-#define PERL_ARGS_ASSERT_ALLOCFILEGV	\
-	assert(gv)
-
 PERL_CALLCONV void*	Perl_any_dup(pTHX_ void* v, const PerlInterpreter* proto_perl)
 			__attribute__warn_unused_result__
 			__attribute__nonnull__(pTHX_2);