X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Frts%2FGC.c;h=448b43bd280514c1ce0e5013a929d8d4650fc837;hb=8d2d17b9bcd6b6dc130ff6a34c177a9971f59435;hp=05728ca3eaa73ea80360d7e94cfd23488b129d97;hpb=d4e0cee2445d9845bb7b0a0687bad84ff32bac28;p=ghc-hetmet.git diff --git a/ghc/rts/GC.c b/ghc/rts/GC.c index 05728ca..448b43b 100644 --- a/ghc/rts/GC.c +++ b/ghc/rts/GC.c @@ -1,5 +1,5 @@ /* ----------------------------------------------------------------------------- - * $Id: GC.c,v 1.57 1999/03/26 10:29:04 simonm Exp $ + * $Id: GC.c,v 1.81 2000/04/27 16:31:46 sewardj Exp $ * * (c) The GHC Team 1998-1999 * @@ -7,6 +7,25 @@ * * ---------------------------------------------------------------------------*/ +//@menu +//* Includes:: +//* STATIC OBJECT LIST:: +//* Static function declarations:: +//* Garbage Collect:: +//* Weak Pointers:: +//* Evacuation:: +//* Scavenging:: +//* Reverting CAFs:: +//* Sanity code for CAF garbage collection:: +//* Lazy black holing:: +//* Stack squeezing:: +//* Pausing a thread:: +//* Index:: +//@end menu + +//@node Includes, STATIC OBJECT LIST +//@subsection Includes + #include "Rts.h" #include "RtsFlags.h" #include "RtsUtils.h" @@ -19,12 +38,23 @@ #include "GC.h" #include "BlockAlloc.h" #include "Main.h" -#include "DebugProf.h" +#include "ProfHeap.h" #include "SchedAPI.h" #include "Weak.h" #include "StablePriv.h" +#include "Prelude.h" +#if defined(GRAN) || defined(PAR) +# include "GranSimRts.h" +# include "ParallelRts.h" +# include "FetchMe.h" +# if defined(DEBUG) +# include "Printer.h" +# include "ParallelDebug.h" +# endif +#endif -StgCAF* enteredCAFs; +//@node STATIC OBJECT LIST, Static function declarations, Includes +//@subsection STATIC OBJECT LIST /* STATIC OBJECT LIST. * @@ -77,11 +107,16 @@ static rtsBool major_gc; */ static nat evac_gen; -/* WEAK POINTERS +/* Weak pointers */ static StgWeak *old_weak_ptr_list; /* also pending finaliser list */ static rtsBool weak_done; /* all done for this pass */ +/* List of all threads during GC + */ +static StgTSO *old_all_threads; +static StgTSO *resurrected_threads; + /* Flag indicating failure to evacuate an object to the desired * generation. */ @@ -91,11 +126,15 @@ static rtsBool failed_to_evac; */ bdescr *old_to_space; + /* Data used for allocation area sizing. */ lnat new_blocks; /* blocks allocated during this GC */ lnat g0s0_pcnt_kept = 30; /* percentage of g0s0 live at last minor GC */ +//@node Static function declarations, Garbage Collect, STATIC OBJECT LIST +//@subsection Static function declarations + /* ----------------------------------------------------------------------------- Static function declarations -------------------------------------------------------------------------- */ @@ -103,7 +142,6 @@ lnat g0s0_pcnt_kept = 30; /* percentage of g0s0 live at last minor GC */ static StgClosure * evacuate ( StgClosure *q ); static void zero_static_object_list ( StgClosure* first_static ); static void zero_mutable_list ( StgMutClosure *first ); -static void revert_dead_CAFs ( void ); static rtsBool traverse_weak_ptr_list ( void ); static void cleanup_weak_ptr_list ( StgWeak **list ); @@ -119,6 +157,9 @@ static void scavenge_mut_once_list ( generation *g ); static void gcCAFs ( void ); #endif +//@node Garbage Collect, Weak Pointers, Static function declarations +//@subsection Garbage Collect + /* ----------------------------------------------------------------------------- GarbageCollect @@ -141,8 +182,9 @@ static void gcCAFs ( void ); - free from-space in each step, and set from-space = to-space. -------------------------------------------------------------------------- */ +//@cindex GarbageCollect -void GarbageCollect(void (*get_roots)(void)) +void GarbageCollect ( void (*get_roots)(void), rtsBool force_major_gc ) { bdescr *bd; step *step; @@ -153,6 +195,11 @@ void GarbageCollect(void (*get_roots)(void)) CostCentreStack *prev_CCS; #endif +#if defined(DEBUG) && defined(GRAN) + IF_DEBUG(gc, belch("@@ Starting garbage collection at %ld (%lx)\n", + Now, Now)); +#endif + /* tell the stats department that we've started a GC */ stat_startGC(); @@ -162,38 +209,28 @@ void GarbageCollect(void (*get_roots)(void)) CCCS = CCS_GC; #endif - /* We might have been called from Haskell land by _ccall_GC, in - * which case we need to call threadPaused() because the scheduler - * won't have done it. - */ - if (CurrentTSO) { threadPaused(CurrentTSO); } - - /* Approximate how much we allocated: number of blocks in the - * nursery + blocks allocated via allocate() - unused nusery blocks. - * This leaves a little slop at the end of each block, and doesn't - * take into account large objects (ToDo). - */ - allocated = (nursery_blocks * BLOCK_SIZE_W) + allocated_bytes(); - for ( bd = current_nursery->link; bd != NULL; bd = bd->link ) { - allocated -= BLOCK_SIZE_W; - } - if (current_nursery->free < current_nursery->start + BLOCK_SIZE_W) { - allocated -= (current_nursery->start + BLOCK_SIZE_W) - - current_nursery->free; - } + /* Approximate how much we allocated */ + allocated = calcAllocated(); /* Figure out which generation to collect */ - N = 0; - for (g = 0; g < RtsFlags.GcFlags.generations; g++) { - if (generations[g].steps[0].n_blocks >= generations[g].max_blocks) { - N = g; + if (force_major_gc) { + N = RtsFlags.GcFlags.generations - 1; + major_gc = rtsTrue; + } else { + N = 0; + for (g = 0; g < RtsFlags.GcFlags.generations; g++) { + if (generations[g].steps[0].n_blocks >= generations[g].max_blocks) { + N = g; + } } + major_gc = (N == RtsFlags.GcFlags.generations-1); } - major_gc = (N == RtsFlags.GcFlags.generations-1); /* check stack sanity *before* GC (ToDo: check all threads) */ - /*IF_DEBUG(sanity, checkTSO(MainTSO,0)); */ +#if defined(GRAN) + // ToDo!: check sanity IF_DEBUG(sanity, checkTSOsSanity()); +#endif IF_DEBUG(sanity, checkFreeListSanity()); /* Initialise the static object lists @@ -313,6 +350,8 @@ void GarbageCollect(void (*get_roots)(void)) /* Do the mut-once lists first */ for (g = RtsFlags.GcFlags.generations-1; g > N; g--) { + IF_PAR_DEBUG(verbose, + printMutOnceList(&generations[g])); scavenge_mut_once_list(&generations[g]); evac_gen = g; for (st = generations[g].n_steps-1; st >= 0; st--) { @@ -321,6 +360,8 @@ void GarbageCollect(void (*get_roots)(void)) } for (g = RtsFlags.GcFlags.generations-1; g > N; g--) { + IF_PAR_DEBUG(verbose, + printMutableList(&generations[g])); scavenge_mutable_list(&generations[g]); evac_gen = g; for (st = generations[g].n_steps-1; st >= 0; st--) { @@ -334,11 +375,18 @@ void GarbageCollect(void (*get_roots)(void)) evac_gen = 0; get_roots(); +#if defined(PAR) /* And don't forget to mark the TSO if we got here direct from * Haskell! */ + /* Not needed in a seq version? if (CurrentTSO) { CurrentTSO = (StgTSO *)MarkRoot((StgClosure *)CurrentTSO); } + */ + + /* Mark the entries in the GALA table of the parallel system */ + markLocalGAs(major_gc); +#endif /* Mark the weak pointer list, and prepare to detect dead weak * pointers. @@ -347,6 +395,13 @@ void GarbageCollect(void (*get_roots)(void)) weak_ptr_list = NULL; weak_done = rtsFalse; + /* The all_threads list is like the weak_ptr_list. + * See traverse_weak_ptr_list() for the details. + */ + old_all_threads = all_threads; + all_threads = END_TSO_QUEUE; + resurrected_threads = END_TSO_QUEUE; + /* Mark the stable pointer table. */ markStablePtrTable(major_gc); @@ -373,6 +428,8 @@ void GarbageCollect(void (*get_roots)(void)) /* scavenge static objects */ if (major_gc && static_objects != END_OF_STATIC_LIST) { + IF_DEBUG(sanity, + checkStaticObjects()); scavenge_static(); } @@ -426,9 +483,13 @@ void GarbageCollect(void (*get_roots)(void)) */ gcStablePtrTable(major_gc); - /* revert dead CAFs and update enteredCAFs list */ - revert_dead_CAFs(); - +#if defined(PAR) + /* Reconstruct the Global Address tables used in GUM */ + rebuildGAtables(major_gc); + IF_DEBUG(sanity, checkGlobalTSOList(rtsTrue/*check TSOs, too*/)); + IF_DEBUG(sanity, checkLAGAtable(rtsTrue/*check closures, too*/)); +#endif + /* Set the maximum blocks for the oldest generation, based on twice * the amount of live data now, adjusted to fit the maximum heap * size if necessary. @@ -600,7 +661,7 @@ void GarbageCollect(void (*get_roots)(void)) int pc_free; adjusted_blocks = (RtsFlags.GcFlags.maxHeapSize - 2 * blocks); - IF_DEBUG(gc, fprintf(stderr, "Near maximum heap size of 0x%x blocks, blocks = %d, adjusted to %d\n", RtsFlags.GcFlags.maxHeapSize, blocks, adjusted_blocks)); + IF_DEBUG(gc, fprintf(stderr, "@@ Near maximum heap size of 0x%x blocks, blocks = %d, adjusted to %d\n", RtsFlags.GcFlags.maxHeapSize, blocks, adjusted_blocks)); pc_free = adjusted_blocks * 100 / RtsFlags.GcFlags.maxHeapSize; if (pc_free < RtsFlags.GcFlags.pcFreeHeap) /* might even be < 0 */ { heapOverflow(); @@ -669,17 +730,14 @@ void GarbageCollect(void (*get_roots)(void)) /* Reset the nursery */ - for (bd = g0s0->blocks; bd; bd = bd->link) { - bd->free = bd->start; - ASSERT(bd->gen == g0); - ASSERT(bd->step == g0s0); - IF_DEBUG(sanity,memset(bd->start, 0xaa, BLOCK_SIZE)); - } - current_nursery = g0s0->blocks; + resetNurseries(); /* start any pending finalizers */ scheduleFinalizers(old_weak_ptr_list); + /* send exceptions to any threads which were about to die */ + resurrectThreads(resurrected_threads); + /* check sanity after GC */ IF_DEBUG(sanity, checkSanity(N)); @@ -693,6 +751,7 @@ void GarbageCollect(void (*get_roots)(void)) /* restore enclosing cost centre */ #ifdef PROFILING + heapCensus(); CCCS = prev_CCS; #endif @@ -703,6 +762,9 @@ void GarbageCollect(void (*get_roots)(void)) stat_endGC(allocated, collected, live, copied, N); } +//@node Weak Pointers, Evacuation, Garbage Collect +//@subsection Weak Pointers + /* ----------------------------------------------------------------------------- Weak Pointers @@ -722,6 +784,7 @@ void GarbageCollect(void (*get_roots)(void)) probably be optimised by keeping per-generation lists of weak pointers, but for a few weak pointers this scheme will work. -------------------------------------------------------------------------- */ +//@cindex traverse_weak_ptr_list static rtsBool traverse_weak_ptr_list(void) @@ -782,7 +845,45 @@ traverse_weak_ptr_list(void) continue; } } - + + /* Now deal with the all_threads list, which behaves somewhat like + * the weak ptr list. If we discover any threads that are about to + * become garbage, we wake them up and administer an exception. + */ + { + StgTSO *t, *tmp, *next, **prev; + + prev = &old_all_threads; + for (t = old_all_threads; t != END_TSO_QUEUE; t = next) { + + /* Threads which have finished or died get dropped from + * the list. + */ + switch (t->what_next) { + case ThreadKilled: + case ThreadComplete: + next = t->global_link; + *prev = next; + continue; + default: + } + + /* Threads which have already been determined to be alive are + * moved onto the all_threads list. + */ + (StgClosure *)tmp = isAlive((StgClosure *)t); + if (tmp != NULL) { + next = tmp->global_link; + tmp->global_link = all_threads; + all_threads = tmp; + *prev = next; + } else { + prev = &(t->global_link); + next = t->global_link; + } + } + } + /* If we didn't make any changes, then we can go round and kill all * the dead weak pointers. The old_weak_ptr list is used as a list * of pending finalizers later on. @@ -792,6 +893,19 @@ traverse_weak_ptr_list(void) for (w = old_weak_ptr_list; w; w = w->link) { w->finalizer = evacuate(w->finalizer); } + + /* And resurrect any threads which were about to become garbage. + */ + { + StgTSO *t, *tmp, *next; + for (t = old_all_threads; t != END_TSO_QUEUE; t = next) { + next = t->global_link; + (StgClosure *)tmp = evacuate((StgClosure *)t); + tmp->global_link = resurrected_threads; + resurrected_threads = tmp; + } + } + weak_done = rtsTrue; } @@ -810,6 +924,8 @@ traverse_weak_ptr_list(void) evacuated need to be evacuated now. -------------------------------------------------------------------------- */ +//@cindex cleanup_weak_ptr_list + static void cleanup_weak_ptr_list ( StgWeak **list ) { @@ -837,10 +953,13 @@ cleanup_weak_ptr_list ( StgWeak **list ) closure if it is alive, or NULL otherwise. -------------------------------------------------------------------------- */ +//@cindex isAlive + StgClosure * isAlive(StgClosure *p) { - StgInfoTable *info; + const StgInfoTable *info; + nat size; while (1) { @@ -871,6 +990,33 @@ isAlive(StgClosure *p) /* alive! */ return ((StgEvacuated *)p)->evacuee; + case BCO: + size = bco_sizeW((StgBCO*)p); + goto large; + + case ARR_WORDS: + size = arr_words_sizeW((StgArrWords *)p); + goto large; + + case MUT_ARR_PTRS: + case MUT_ARR_PTRS_FROZEN: + size = mut_arr_ptrs_sizeW((StgMutArrPtrs *)p); + goto large; + + case TSO: + if (((StgTSO *)p)->what_next == ThreadRelocated) { + p = (StgClosure *)((StgTSO *)p)->link; + continue; + } + + size = tso_sizeW((StgTSO *)p); + large: + if (size >= LARGE_OBJECT_THRESHOLD/sizeof(W_) + && Bdescr((P_)p)->evacuated) + return p; + else + return NULL; + default: /* dead. */ return NULL; @@ -878,12 +1024,21 @@ isAlive(StgClosure *p) } } +//@cindex MarkRoot StgClosure * MarkRoot(StgClosure *root) { +# if 0 && defined(PAR) && defined(DEBUG) + StgClosure *foo = evacuate(root); + // ASSERT(closure_STATIC(foo) || maybeLarge(foo) || Bdescr(foo)->evacuated); + ASSERT(isAlive(foo)); // must be in to-space + return foo; +# else return evacuate(root); +# endif } +//@cindex addBlock static void addBlock(step *step) { bdescr *bd = allocBlock(); @@ -905,6 +1060,8 @@ static void addBlock(step *step) new_blocks++; } +//@cindex upd_evacuee + static __inline__ void upd_evacuee(StgClosure *p, StgClosure *dest) { @@ -912,6 +1069,8 @@ upd_evacuee(StgClosure *p, StgClosure *dest) ((StgEvacuated *)p)->evacuee = dest; } +//@cindex copy + static __inline__ StgClosure * copy(StgClosure *src, nat size, step *step) { @@ -953,6 +1112,8 @@ copy(StgClosure *src, nat size, step *step) * used to optimise evacuation of BLACKHOLEs. */ +//@cindex copyPart + static __inline__ StgClosure * copyPart(StgClosure *src, nat size_to_reserve, nat size_to_copy, step *step) { @@ -981,6 +1142,9 @@ copyPart(StgClosure *src, nat size_to_reserve, nat size_to_copy, step *step) return (StgClosure *)dest; } +//@node Evacuation, Scavenging, Weak Pointers +//@subsection Evacuation + /* ----------------------------------------------------------------------------- Evacuate a large object @@ -992,6 +1156,8 @@ copyPart(StgClosure *src, nat size_to_reserve, nat size_to_copy, step *step) evacuated, or 0 otherwise. -------------------------------------------------------------------------- */ +//@cindex evacuate_large + static inline void evacuate_large(StgPtr p, rtsBool mutable) { @@ -1054,6 +1220,8 @@ evacuate_large(StgPtr p, rtsBool mutable) the promotion until the next GC. -------------------------------------------------------------------------- */ +//@cindex mkMutCons + static StgClosure * mkMutCons(StgClosure *ptr, generation *gen) { @@ -1103,7 +1271,7 @@ mkMutCons(StgClosure *ptr, generation *gen) didn't manage to evacuate this object into evac_gen. -------------------------------------------------------------------------- */ - +//@cindex evacuate static StgClosure * evacuate(StgClosure *q) @@ -1130,16 +1298,38 @@ loop: } step = bd->step->to; } +#ifdef DEBUG + else step = NULL; /* make sure copy() will crash if HEAP_ALLOCED is wrong */ +#endif /* make sure the info pointer is into text space */ ASSERT(q && (LOOKS_LIKE_GHC_INFO(GET_INFO(q)) || IS_HUGS_CONSTR_INFO(GET_INFO(q)))); - info = get_itbl(q); + /* + if (info->type==RBH) { + info = REVERT_INFOPTR(info); + IF_DEBUG(gc, + belch("@_ Trying to evacuate an RBH %p (%s); reverting to IP %p (%s)", + q, info_type(q), info, info_type_by_ip(info))); + } + */ + switch (info -> type) { case BCO: - return copy(q,bco_sizeW(stgCast(StgBCO*,q)),step); + { + nat size = bco_sizeW((StgBCO*)q); + + if (size >= LARGE_OBJECT_THRESHOLD/sizeof(W_)) { + evacuate_large((P_)q, rtsFalse); + to = q; + } else { + /* just copy the block */ + to = copy(q,size,step); + } + return to; + } case MUT_VAR: ASSERT(q->header.info != &MUT_CONS_info); @@ -1189,6 +1379,8 @@ loop: return copy(q,sizeW_fromITBL(info),step); case CAF_BLACKHOLE: + case SE_CAF_BLACKHOLE: + case SE_BLACKHOLE: case BLACKHOLE: return copyPart(q,BLACKHOLE_sizeW(),sizeofW(StgHeader),step); @@ -1249,15 +1441,15 @@ loop: case IND_PERM: case IND_OLDGEN: case IND_OLDGEN_PERM: - selectee = stgCast(StgInd *,selectee)->indirectee; + selectee = ((StgInd *)selectee)->indirectee; goto selector_loop; case CAF_ENTERED: - selectee = stgCast(StgCAF *,selectee)->value; + selectee = ((StgCAF *)selectee)->value; goto selector_loop; case EVACUATED: - selectee = stgCast(StgEvacuated*,selectee)->evacuee; + selectee = ((StgEvacuated *)selectee)->evacuee; goto selector_loop; case THUNK: @@ -1271,13 +1463,16 @@ loop: /* aargh - do recursively???? */ case CAF_UNENTERED: case CAF_BLACKHOLE: + case SE_CAF_BLACKHOLE: + case SE_BLACKHOLE: case BLACKHOLE: case BLACKHOLE_BQ: /* not evaluated yet */ break; default: - barf("evacuate: THUNK_SELECTOR: strange selectee"); + barf("evacuate: THUNK_SELECTOR: strange selectee %d", + (int)(selectee_info->type)); } } return copy(q,THUNK_SELECTOR_sizeW(),step); @@ -1337,13 +1532,26 @@ loop: case CATCH_FRAME: case SEQ_FRAME: /* shouldn't see these */ - barf("evacuate: stack frame\n"); + barf("evacuate: stack frame at %p\n", q); case AP_UPD: case PAP: - /* these are special - the payload is a copy of a chunk of stack, - tagging and all. */ - return copy(q,pap_sizeW(stgCast(StgPAP*,q)),step); + /* PAPs and AP_UPDs are special - the payload is a copy of a chunk + * of stack, tagging and all. + * + * They can be larger than a block in size. Both are only + * allocated via allocate(), so they should be chained on to the + * large_object list. + */ + { + nat size = pap_sizeW((StgPAP*)q); + if (size >= LARGE_OBJECT_THRESHOLD/sizeof(W_)) { + evacuate_large((P_)q, rtsFalse); + return q; + } else { + return copy(q,size,step); + } + } case EVACUATED: /* Already evacuated, just return the forwarding address. @@ -1356,7 +1564,7 @@ loop: if (evac_gen > 0) { /* optimisation */ StgClosure *p = ((StgEvacuated*)q)->evacuee; if (Bdescr((P_)p)->gen->no < evac_gen) { - /* fprintf(stderr,"evac failed!\n");*/ + IF_DEBUG(gc, belch("@@ evacuate: evac of EVACUATED node %p failed!", p)); failed_to_evac = rtsTrue; TICK_GC_FAILED_PROMOTION(); } @@ -1365,7 +1573,7 @@ loop: case ARR_WORDS: { - nat size = arr_words_sizeW(stgCast(StgArrWords*,q)); + nat size = arr_words_sizeW((StgArrWords *)q); if (size >= LARGE_OBJECT_THRESHOLD/sizeof(W_)) { evacuate_large((P_)q, rtsFalse); @@ -1379,7 +1587,7 @@ loop: case MUT_ARR_PTRS: case MUT_ARR_PTRS_FROZEN: { - nat size = mut_arr_ptrs_sizeW(stgCast(StgMutArrPtrs*,q)); + nat size = mut_arr_ptrs_sizeW((StgMutArrPtrs *)q); if (size >= LARGE_OBJECT_THRESHOLD/sizeof(W_)) { evacuate_large((P_)q, info->type == MUT_ARR_PTRS); @@ -1396,10 +1604,17 @@ loop: case TSO: { - StgTSO *tso = stgCast(StgTSO *,q); + StgTSO *tso = (StgTSO *)q; nat size = tso_sizeW(tso); int diff; + /* Deal with redirected TSOs (a TSO that's had its stack enlarged). + */ + if (tso->what_next == ThreadRelocated) { + q = (StgClosure *)tso->link; + goto loop; + } + /* Large TSOs don't get moved, so no relocation is required. */ if (size >= LARGE_OBJECT_THRESHOLD/sizeof(W_)) { @@ -1426,13 +1641,47 @@ loop: } } +#if defined(PAR) + case RBH: // cf. BLACKHOLE_BQ + { + //StgInfoTable *rip = get_closure_info(q, &size, &ptrs, &nonptrs, &vhs, str); + to = copy(q,BLACKHOLE_sizeW(),step); + //ToDo: derive size etc from reverted IP + //to = copy(q,size,step); + recordMutable((StgMutClosure *)to); + IF_DEBUG(gc, + belch("@@ evacuate: RBH %p (%s) to %p (%s)", + q, info_type(q), to, info_type(to))); + return to; + } + case BLOCKED_FETCH: + ASSERT(sizeofW(StgBlockedFetch) >= MIN_NONUPD_SIZE); + to = copy(q,sizeofW(StgBlockedFetch),step); + IF_DEBUG(gc, + belch("@@ evacuate: %p (%s) to %p (%s)", + q, info_type(q), to, info_type(to))); + return to; + case FETCH_ME: - fprintf(stderr,"evacuate: unimplemented/strange closure type\n"); - return q; + ASSERT(sizeofW(StgBlockedFetch) >= MIN_UPD_SIZE); + to = copy(q,sizeofW(StgFetchMe),step); + IF_DEBUG(gc, + belch("@@ evacuate: %p (%s) to %p (%s)", + q, info_type(q), to, info_type(to))); + return to; + + case FETCH_ME_BQ: + ASSERT(sizeofW(StgBlockedFetch) >= MIN_UPD_SIZE); + to = copy(q,sizeofW(StgFetchMeBlockingQueue),step); + IF_DEBUG(gc, + belch("@@ evacuate: %p (%s) to %p (%s)", + q, info_type(q), to, info_type(to))); + return to; +#endif default: - barf("evacuate: strange closure type"); + barf("evacuate: strange closure type %d", (int)(info->type)); } barf("evacuate"); @@ -1442,6 +1691,7 @@ loop: relocate_TSO is called just after a TSO has been copied from src to dest. It adjusts the update frame list for the new location. -------------------------------------------------------------------------- */ +//@cindex relocate_TSO StgTSO * relocate_TSO(StgTSO *src, StgTSO *dest) @@ -1482,7 +1732,7 @@ relocate_TSO(StgTSO *src, StgTSO *dest) break; default: - barf("relocate_TSO"); + barf("relocate_TSO %d", (int)(get_itbl(su)->type)); } break; } @@ -1490,6 +1740,11 @@ relocate_TSO(StgTSO *src, StgTSO *dest) return dest; } +//@node Scavenging, Reverting CAFs, Evacuation +//@subsection Scavenging + +//@cindex scavenge_srt + static inline void scavenge_srt(const StgInfoTable *info) { @@ -1499,7 +1754,7 @@ scavenge_srt(const StgInfoTable *info) * srt field in the info table. That's ok, because we'll * never dereference it. */ - srt = stgCast(StgClosure **,info->srt); + srt = (StgClosure **)(info->srt); srt_end = srt + info->srt_len; for (; srt < srt_end; srt++) { /* Special-case to handle references to closures hiding out in DLLs, since @@ -1511,8 +1766,8 @@ scavenge_srt(const StgInfoTable *info) If the SRT entry hasn't got bit 0 set, the SRT entry points to a closure that's fixed at link-time, and no extra magic is required. */ -#ifdef HAVE_WIN32_DLL_SUPPORT - if ( stgCast(unsigned long,*srt) & 0x1 ) { +#ifdef ENABLE_WIN32_DLL_SUPPORT + if ( (unsigned long)(*srt) & 0x1 ) { evacuate(*stgCast(StgClosure**,(stgCast(unsigned long, *srt) & ~0x1))); } else { evacuate(*srt); @@ -1524,6 +1779,33 @@ scavenge_srt(const StgInfoTable *info) } /* ----------------------------------------------------------------------------- + Scavenge a TSO. + -------------------------------------------------------------------------- */ + +static void +scavengeTSO (StgTSO *tso) +{ + /* chase the link field for any TSOs on the same queue */ + (StgClosure *)tso->link = evacuate((StgClosure *)tso->link); + if ( tso->why_blocked == BlockedOnMVar + || tso->why_blocked == BlockedOnBlackHole + || tso->why_blocked == BlockedOnException +#if defined(PAR) + || tso->why_blocked == BlockedOnGA + || tso->why_blocked == BlockedOnGA_NoSend +#endif + ) { + tso->block_info.closure = evacuate(tso->block_info.closure); + } + if ( tso->blocked_exceptions != NULL ) { + tso->blocked_exceptions = + (StgTSO *)evacuate((StgClosure *)tso->blocked_exceptions); + } + /* scavenge this thread's stack */ + scavenge_stack(tso->sp, &(tso->stack[tso->stack_size])); +} + +/* ----------------------------------------------------------------------------- Scavenge a given step until there are no more objects in this step to scavenge. @@ -1535,7 +1817,7 @@ scavenge_srt(const StgInfoTable *info) scavenging a mutable object where early promotion isn't such a good idea. -------------------------------------------------------------------------- */ - +//@cindex scavenge static void scavenge(step *step) @@ -1569,11 +1851,16 @@ scavenge(step *step) || IS_HUGS_CONSTR_INFO(GET_INFO((StgClosure *)p)))); info = get_itbl((StgClosure *)p); + /* + if (info->type==RBH) + info = REVERT_INFOPTR(info); + */ + switch (info -> type) { case BCO: { - StgBCO* bco = stgCast(StgBCO*,p); + StgBCO* bco = (StgBCO *)p; nat i; for (i = 0; i < bco->n_ptrs; i++) { bcoConstCPtr(bco,i) = evacuate(bcoConstCPtr(bco,i)); @@ -1722,6 +2009,8 @@ scavenge(step *step) break; case CAF_BLACKHOLE: + case SE_CAF_BLACKHOLE: + case SE_BLACKHOLE: case BLACKHOLE: p += BLACKHOLE_sizeW(); break; @@ -1780,7 +2069,7 @@ scavenge(step *step) * evacuate the function pointer too... */ { - StgPAP* pap = stgCast(StgPAP*,p); + StgPAP* pap = (StgPAP *)p; pap->fun = evacuate(pap->fun); scavenge_stack((P_)pap->payload, (P_)pap->payload + pap->n_args); @@ -1790,7 +2079,7 @@ scavenge(step *step) case ARR_WORDS: /* nothing to follow */ - p += arr_words_sizeW(stgCast(StgArrWords*,p)); + p += arr_words_sizeW((StgArrWords *)p); break; case MUT_ARR_PTRS: @@ -1826,29 +2115,87 @@ scavenge(step *step) case TSO: { - StgTSO *tso; - - tso = (StgTSO *)p; + StgTSO *tso = (StgTSO *)p; evac_gen = 0; - /* chase the link field for any TSOs on the same queue */ - (StgClosure *)tso->link = evacuate((StgClosure *)tso->link); - if (tso->blocked_on) { - tso->blocked_on = evacuate(tso->blocked_on); - } - /* scavenge this thread's stack */ - scavenge_stack(tso->sp, &(tso->stack[tso->stack_size])); + scavengeTSO(tso); evac_gen = saved_evac_gen; p += tso_sizeW(tso); break; } +#if defined(PAR) + case RBH: // cf. BLACKHOLE_BQ + { + // nat size, ptrs, nonptrs, vhs; + // char str[80]; + // StgInfoTable *rip = get_closure_info(p, &size, &ptrs, &nonptrs, &vhs, str); + StgRBH *rbh = (StgRBH *)p; + (StgClosure *)rbh->blocking_queue = + evacuate((StgClosure *)rbh->blocking_queue); + if (failed_to_evac) { + failed_to_evac = rtsFalse; + recordMutable((StgMutClosure *)rbh); + } + IF_DEBUG(gc, + belch("@@ scavenge: RBH %p (%s) (new blocking_queue link=%p)", + p, info_type(p), (StgClosure *)rbh->blocking_queue)); + // ToDo: use size of reverted closure here! + p += BLACKHOLE_sizeW(); + break; + } + case BLOCKED_FETCH: + { + StgBlockedFetch *bf = (StgBlockedFetch *)p; + /* follow the pointer to the node which is being demanded */ + (StgClosure *)bf->node = + evacuate((StgClosure *)bf->node); + /* follow the link to the rest of the blocking queue */ + (StgClosure *)bf->link = + evacuate((StgClosure *)bf->link); + if (failed_to_evac) { + failed_to_evac = rtsFalse; + recordMutable((StgMutClosure *)bf); + } + IF_DEBUG(gc, + belch("@@ scavenge: %p (%s); node is now %p; exciting, isn't it", + bf, info_type((StgClosure *)bf), + bf->node, info_type(bf->node))); + p += sizeofW(StgBlockedFetch); + break; + } + case FETCH_ME: + IF_DEBUG(gc, + belch("@@ scavenge: HWL claims nothing to do for %p (%s)", + p, info_type((StgClosure *)p))); + p += sizeofW(StgFetchMe); + break; // nothing to do in this case + + case FETCH_ME_BQ: // cf. BLACKHOLE_BQ + { + StgFetchMeBlockingQueue *fmbq = (StgFetchMeBlockingQueue *)p; + (StgClosure *)fmbq->blocking_queue = + evacuate((StgClosure *)fmbq->blocking_queue); + if (failed_to_evac) { + failed_to_evac = rtsFalse; + recordMutable((StgMutClosure *)fmbq); + } + IF_DEBUG(gc, + belch("@@ scavenge: %p (%s) exciting, isn't it", + p, info_type((StgClosure *)p))); + p += sizeofW(StgFetchMeBlockingQueue); + break; + } +#endif + case EVACUATED: - barf("scavenge: unimplemented/strange closure type\n"); + barf("scavenge: unimplemented/strange closure type %d @ %p", + info->type, p); default: - barf("scavenge"); + barf("scavenge: unimplemented/strange closure type %d @ %p", + info->type, p); } /* If we didn't manage to promote all the objects pointed to by @@ -1872,10 +2219,12 @@ scavenge(step *step) because they contain old-to-new generation pointers. Only certain objects can have this property. -------------------------------------------------------------------------- */ +//@cindex scavenge_one + static rtsBool scavenge_one(StgClosure *p) { - StgInfoTable *info; + const StgInfoTable *info; rtsBool no_luck; ASSERT(p && (LOOKS_LIKE_GHC_INFO(GET_INFO(p)) @@ -1883,6 +2232,11 @@ scavenge_one(StgClosure *p) info = get_itbl(p); + /* ngoq moHqu'! + if (info->type==RBH) + info = REVERT_INFOPTR(info); // if it's an RBH, look at the orig closure + */ + switch (info -> type) { case FUN: @@ -1919,6 +2273,8 @@ scavenge_one(StgClosure *p) } case CAF_BLACKHOLE: + case SE_CAF_BLACKHOLE: + case SE_BLACKHOLE: case BLACKHOLE: break; @@ -1951,7 +2307,7 @@ scavenge_one(StgClosure *p) break; default: - barf("scavenge_one: strange object"); + barf("scavenge_one: strange object %d", (int)(info->type)); } no_luck = failed_to_evac; @@ -1967,11 +2323,12 @@ scavenge_one(StgClosure *p) generations older than the one being collected) as roots. We also remove non-mutable objects from the mutable list at this point. -------------------------------------------------------------------------- */ +//@cindex scavenge_mut_once_list static void scavenge_mut_once_list(generation *gen) { - StgInfoTable *info; + const StgInfoTable *info; StgMutClosure *p, *next, *new_list; p = gen->mut_once_list; @@ -1988,6 +2345,10 @@ scavenge_mut_once_list(generation *gen) || IS_HUGS_CONSTR_INFO(GET_INFO(p)))); info = get_itbl(p); + /* + if (info->type==RBH) + info = REVERT_INFOPTR(info); // if it's an RBH, look at the orig closure + */ switch(info->type) { case IND_OLDGEN: @@ -1999,7 +2360,8 @@ scavenge_mut_once_list(generation *gen) ((StgIndOldGen *)p)->indirectee = evacuate(((StgIndOldGen *)p)->indirectee); -#if 0 +#ifdef DEBUG + if (RtsFlags.DebugFlags.gc) /* Debugging code to print out the size of the thing we just * promoted */ @@ -2091,18 +2453,19 @@ scavenge_mut_once_list(generation *gen) default: /* shouldn't have anything else on the mutables list */ - barf("scavenge_mut_once_list: strange object?"); + barf("scavenge_mut_once_list: strange object? %d", (int)(info->type)); } } gen->mut_once_list = new_list; } +//@cindex scavenge_mutable_list static void scavenge_mutable_list(generation *gen) { - StgInfoTable *info; + const StgInfoTable *info; StgMutClosure *p, *next; p = gen->saved_mut_list; @@ -2118,6 +2481,10 @@ scavenge_mutable_list(generation *gen) || IS_HUGS_CONSTR_INFO(GET_INFO(p)))); info = get_itbl(p); + /* + if (info->type==RBH) + info = REVERT_INFOPTR(info); // if it's an RBH, look at the orig closure + */ switch(info->type) { case MUT_ARR_PTRS_FROZEN: @@ -2182,11 +2549,7 @@ scavenge_mutable_list(generation *gen) { StgTSO *tso = (StgTSO *)p; - (StgClosure *)tso->link = evacuate((StgClosure *)tso->link); - if (tso->blocked_on) { - tso->blocked_on = evacuate(tso->blocked_on); - } - scavenge_stack(tso->sp, &(tso->stack[tso->stack_size])); + scavengeTSO(tso); /* Don't take this TSO off the mutable list - it might still * point to some younger objects (because we set evac_gen to 0 @@ -2207,13 +2570,91 @@ scavenge_mutable_list(generation *gen) continue; } + /* Happens if a BLACKHOLE_BQ in the old generation is updated: + */ + case IND_OLDGEN: + case IND_OLDGEN_PERM: + /* Try to pull the indirectee into this generation, so we can + * remove the indirection from the mutable list. + */ + evac_gen = gen->no; + ((StgIndOldGen *)p)->indirectee = + evacuate(((StgIndOldGen *)p)->indirectee); + evac_gen = 0; + + if (failed_to_evac) { + failed_to_evac = rtsFalse; + p->mut_link = gen->mut_once_list; + gen->mut_once_list = p; + } else { + p->mut_link = NULL; + } + continue; + +#if defined(PAR) + // HWL: check whether all of these are necessary + + case RBH: // cf. BLACKHOLE_BQ + { + // nat size, ptrs, nonptrs, vhs; + // char str[80]; + // StgInfoTable *rip = get_closure_info(p, &size, &ptrs, &nonptrs, &vhs, str); + StgRBH *rbh = (StgRBH *)p; + (StgClosure *)rbh->blocking_queue = + evacuate((StgClosure *)rbh->blocking_queue); + if (failed_to_evac) { + failed_to_evac = rtsFalse; + recordMutable((StgMutClosure *)rbh); + } + // ToDo: use size of reverted closure here! + p += BLACKHOLE_sizeW(); + break; + } + + case BLOCKED_FETCH: + { + StgBlockedFetch *bf = (StgBlockedFetch *)p; + /* follow the pointer to the node which is being demanded */ + (StgClosure *)bf->node = + evacuate((StgClosure *)bf->node); + /* follow the link to the rest of the blocking queue */ + (StgClosure *)bf->link = + evacuate((StgClosure *)bf->link); + if (failed_to_evac) { + failed_to_evac = rtsFalse; + recordMutable((StgMutClosure *)bf); + } + p += sizeofW(StgBlockedFetch); + break; + } + + case FETCH_ME: + p += sizeofW(StgFetchMe); + break; // nothing to do in this case + + case FETCH_ME_BQ: // cf. BLACKHOLE_BQ + { + StgFetchMeBlockingQueue *fmbq = (StgFetchMeBlockingQueue *)p; + (StgClosure *)fmbq->blocking_queue = + evacuate((StgClosure *)fmbq->blocking_queue); + if (failed_to_evac) { + failed_to_evac = rtsFalse; + recordMutable((StgMutClosure *)fmbq); + } + p += sizeofW(StgFetchMeBlockingQueue); + break; + } +#endif + default: /* shouldn't have anything else on the mutables list */ - barf("scavenge_mut_list: strange object?"); + barf("scavenge_mutable_list: strange object? %d", (int)(info->type)); } } } +//@cindex scavenge_static + static void scavenge_static(void) { @@ -2229,7 +2670,10 @@ scavenge_static(void) while (p != END_OF_STATIC_LIST) { info = get_itbl(p); - + /* + if (info->type==RBH) + info = REVERT_INFOPTR(info); // if it's an RBH, look at the orig closure + */ /* make sure the info pointer is into text space */ ASSERT(p && (LOOKS_LIKE_GHC_INFO(GET_INFO(p)) || IS_HUGS_CONSTR_INFO(GET_INFO(p)))); @@ -2280,12 +2724,12 @@ scavenge_static(void) } default: - barf("scavenge_static"); + barf("scavenge_static: strange closure %d", (int)(info->type)); } ASSERT(failed_to_evac == rtsFalse); - /* get the next static object from the list. Remeber, there might + /* get the next static object from the list. Remember, there might * be more stuff on this list now that we've done some evacuating! * (static_objects is a global) */ @@ -2298,6 +2742,7 @@ scavenge_static(void) objects pointed to by it. We can use the same code for walking PAPs, since these are just sections of copied stack. -------------------------------------------------------------------------- */ +//@cindex scavenge_stack static void scavenge_stack(StgPtr p, StgPtr stack_end) @@ -2306,6 +2751,8 @@ scavenge_stack(StgPtr p, StgPtr stack_end) const StgInfoTable* info; StgWord32 bitmap; + //IF_DEBUG(sanity, belch(" scavenging stack between %p and %p", p, stack_end)); + /* * Each time around this loop, we are looking at a chunk of stack * that starts with either a pending argument section or an @@ -2323,11 +2770,10 @@ scavenge_stack(StgPtr p, StgPtr stack_end) /* Is q a pointer to a closure? */ - - if (! LOOKS_LIKE_GHC_INFO(q)) { + if (! LOOKS_LIKE_GHC_INFO(q) ) { #ifdef DEBUG if ( 0 && LOOKS_LIKE_STATIC_CLOSURE(q) ) { /* Is it a static closure? */ - ASSERT(closure_STATIC(stgCast(StgClosure*,q))); + ASSERT(closure_STATIC((StgClosure *)q)); } /* otherwise, must be a pointer into the allocation space. */ #endif @@ -2355,8 +2801,18 @@ scavenge_stack(StgPtr p, StgPtr stack_end) /* probably a slow-entry point return address: */ case FUN: case FUN_STATIC: - p++; + { +#if 0 + StgPtr old_p = p; + p++; p++; + IF_DEBUG(sanity, + belch("HWL: scavenge_stack: FUN(_STATIC) adjusting p from %p to %p (instead of %p)", + old_p, p, old_p+1)); +#else + p++; /* what if FHS!=1 !? -- HWL */ +#endif goto follow_srt; + } /* Specialised code for update frames, since they're so common. * We *know* the updatee points to a BLACKHOLE, CAF_BLACKHOLE, @@ -2403,20 +2859,23 @@ scavenge_stack(StgPtr p, StgPtr stack_end) recordMutable((StgMutClosure *)to); continue; default: + /* will never be SE_{,CAF_}BLACKHOLE, since we + don't push an update frame for single-entry thunks. KSW 1999-01. */ barf("scavenge_stack: UPDATE_FRAME updatee"); } } } /* small bitmap (< 32 entries, or 64 on a 64-bit machine) */ - case RET_BCO: - case RET_SMALL: - case RET_VEC_SMALL: case STOP_FRAME: case CATCH_FRAME: case SEQ_FRAME: + case RET_BCO: + case RET_SMALL: + case RET_VEC_SMALL: bitmap = info->layout.bitmap; p++; + /* this assumes that the payload starts immediately after the info-ptr */ small_bitmap: while (bitmap != 0) { if ((bitmap & 1) == 0) { @@ -2464,7 +2923,7 @@ scavenge_stack(StgPtr p, StgPtr stack_end) } default: - barf("scavenge_stack: weird activation record found on stack.\n"); + barf("scavenge_stack: weird activation record found on stack: %d", (int)(info->type)); } } } @@ -2477,6 +2936,7 @@ scavenge_stack(StgPtr p, StgPtr stack_end) objects are (repeatedly) mutable, so most of the time evac_gen will be zero. --------------------------------------------------------------------------- */ +//@cindex scavenge_large static void scavenge_large(step *step) @@ -2500,7 +2960,7 @@ scavenge_large(step *step) dbl_link_onto(bd, &step->scavenged_large_objects); p = bd->start; - info = get_itbl(stgCast(StgClosure*,p)); + info = get_itbl((StgClosure *)p); switch (info->type) { @@ -2541,7 +3001,7 @@ scavenge_large(step *step) case BCO: { - StgBCO* bco = stgCast(StgBCO*,p); + StgBCO* bco = (StgBCO *)p; nat i; evac_gen = saved_evac_gen; for (i = 0; i < bco->n_ptrs; i++) { @@ -2552,26 +3012,29 @@ scavenge_large(step *step) } case TSO: + scavengeTSO((StgTSO *)p); + continue; + + case AP_UPD: + case PAP: { - StgTSO *tso; + StgPAP* pap = (StgPAP *)p; - tso = (StgTSO *)p; - /* chase the link field for any TSOs on the same queue */ - (StgClosure *)tso->link = evacuate((StgClosure *)tso->link); - if (tso->blocked_on) { - tso->blocked_on = evacuate(tso->blocked_on); - } - /* scavenge this thread's stack */ - scavenge_stack(tso->sp, &(tso->stack[tso->stack_size])); + evac_gen = saved_evac_gen; /* not really mutable */ + pap->fun = evacuate(pap->fun); + scavenge_stack((P_)pap->payload, (P_)pap->payload + pap->n_args); + evac_gen = 0; continue; } default: - barf("scavenge_large: unknown/strange object"); + barf("scavenge_large: unknown/strange object %d", (int)(info->type)); } } } +//@cindex zero_static_object_list + static void zero_static_object_list(StgClosure* first_static) { @@ -2594,6 +3057,8 @@ zero_static_object_list(StgClosure* first_static) * It doesn't do any harm to zero all the mutable link fields on the * mutable list. */ +//@cindex zero_mutable_list + static void zero_mutable_list( StgMutClosure *first ) { @@ -2605,44 +3070,43 @@ zero_mutable_list( StgMutClosure *first ) } } +//@node Reverting CAFs, Sanity code for CAF garbage collection, Scavenging +//@subsection Reverting CAFs + /* ----------------------------------------------------------------------------- Reverting CAFs -------------------------------------------------------------------------- */ +//@cindex RevertCAFs void RevertCAFs(void) { - while (enteredCAFs != END_CAF_LIST) { - StgCAF* caf = enteredCAFs; - - enteredCAFs = caf->link; - ASSERT(get_itbl(caf)->type == CAF_ENTERED); - SET_INFO(caf,&CAF_UNENTERED_info); - caf->value = stgCast(StgClosure*,0xdeadbeef); - caf->link = stgCast(StgCAF*,0xdeadbeef); - } - enteredCAFs = END_CAF_LIST; +#ifdef INTERPRETER + StgInt i; + + /* Deal with CAFs created by compiled code. */ + for (i = 0; i < usedECafTable; i++) { + SET_INFO( (StgInd*)(ecafTable[i].closure), ecafTable[i].origItbl ); + ((StgInd*)(ecafTable[i].closure))->indirectee = 0; + } + + /* Deal with CAFs created by the interpreter. */ + while (ecafList != END_ECAF_LIST) { + StgCAF* caf = ecafList; + ecafList = caf->link; + ASSERT(get_itbl(caf)->type == CAF_ENTERED); + SET_INFO(caf,&CAF_UNENTERED_info); + caf->value = (StgClosure *)0xdeadbeef; + caf->link = (StgCAF *)0xdeadbeef; + } + + /* Empty out both the table and the list. */ + clearECafTable(); + ecafList = END_ECAF_LIST; +#endif } -void revert_dead_CAFs(void) -{ - StgCAF* caf = enteredCAFs; - enteredCAFs = END_CAF_LIST; - while (caf != END_CAF_LIST) { - StgCAF *next, *new; - next = caf->link; - new = (StgCAF*)isAlive((StgClosure*)caf); - if (new) { - new->link = enteredCAFs; - enteredCAFs = new; - } else { - ASSERT(0); - SET_INFO(caf,&CAF_UNENTERED_info); - caf->value = (StgClosure*)0xdeadbeef; - caf->link = (StgCAF*)0xdeadbeef; - } - caf = next; - } -} +//@node Sanity code for CAF garbage collection, Lazy black holing, Reverting CAFs +//@subsection Sanity code for CAF garbage collection /* ----------------------------------------------------------------------------- Sanity code for CAF garbage collection. @@ -2657,6 +3121,8 @@ void revert_dead_CAFs(void) -------------------------------------------------------------------------- */ #ifdef DEBUG +//@cindex gcCAFs + static void gcCAFs(void) { @@ -2694,6 +3160,9 @@ gcCAFs(void) } #endif +//@node Lazy black holing, Stack squeezing, Sanity code for CAF garbage collection +//@subsection Lazy black holing + /* ----------------------------------------------------------------------------- Lazy black holing. @@ -2701,6 +3170,7 @@ gcCAFs(void) some work, we have to run down the stack and black-hole all the closures referred to by update frames. -------------------------------------------------------------------------- */ +//@cindex threadLazyBlackHole static void threadLazyBlackHole(StgTSO *tso) @@ -2716,7 +3186,7 @@ threadLazyBlackHole(StgTSO *tso) switch (get_itbl(update_frame)->type) { case CATCH_FRAME: - update_frame = stgCast(StgCatchFrame*,update_frame)->link; + update_frame = ((StgCatchFrame *)update_frame)->link; break; case UPDATE_FRAME: @@ -2735,6 +3205,9 @@ threadLazyBlackHole(StgTSO *tso) if (bh->header.info != &BLACKHOLE_BQ_info && bh->header.info != &CAF_BLACKHOLE_info) { +#if (!defined(LAZY_BLACKHOLING)) && defined(DEBUG) + fprintf(stderr,"Unexpected lazy BHing required at 0x%04x\n",(int)bh); +#endif SET_INFO(bh,&BLACKHOLE_info); } @@ -2742,7 +3215,7 @@ threadLazyBlackHole(StgTSO *tso) break; case SEQ_FRAME: - update_frame = stgCast(StgSeqFrame*,update_frame)->link; + update_frame = ((StgSeqFrame *)update_frame)->link; break; case STOP_FRAME: @@ -2753,6 +3226,9 @@ threadLazyBlackHole(StgTSO *tso) } } +//@node Stack squeezing, Pausing a thread, Lazy black holing +//@subsection Stack squeezing + /* ----------------------------------------------------------------------------- * Stack squeezing * @@ -2760,6 +3236,7 @@ threadLazyBlackHole(StgTSO *tso) * lazy black holing here. * * -------------------------------------------------------------------------- */ +//@cindex threadSqueezeStack static void threadSqueezeStack(StgTSO *tso) @@ -2770,6 +3247,14 @@ threadSqueezeStack(StgTSO *tso) StgUpdateFrame *prev_frame; /* Temporally previous */ StgPtr bottom; rtsBool prev_was_update_frame; +#if DEBUG + StgUpdateFrame *top_frame; + nat upd_frames=0, stop_frames=0, catch_frames=0, seq_frames=0, + bhs=0, squeezes=0; + void printObj( StgClosure *obj ); // from Printer.c + + top_frame = tso->su; +#endif bottom = &(tso->stack[tso->stack_size]); frame = tso->su; @@ -2795,6 +3280,30 @@ threadSqueezeStack(StgTSO *tso) frame->link = next_frame; next_frame = frame; frame = prev_frame; +#if DEBUG + IF_DEBUG(sanity, + if (!(frame>=top_frame && frame<=(StgUpdateFrame *)bottom)) { + printObj((StgClosure *)prev_frame); + barf("threadSqueezeStack: current frame is rubbish %p; previous was %p\n", + frame, prev_frame); + }) + switch (get_itbl(frame)->type) { + case UPDATE_FRAME: upd_frames++; + if (frame->updatee->header.info == &BLACKHOLE_info) + bhs++; + break; + case STOP_FRAME: stop_frames++; + break; + case CATCH_FRAME: catch_frames++; + break; + case SEQ_FRAME: seq_frames++; + break; + default: + barf("Found non-frame during stack squeezing at %p (prev frame was %p)\n", + frame, prev_frame); + printObj((StgClosure *)prev_frame); + } +#endif if (get_itbl(frame)->type == UPDATE_FRAME && frame->updatee->header.info == &BLACKHOLE_info) { break; @@ -2844,8 +3353,9 @@ threadSqueezeStack(StgTSO *tso) StgClosure *updatee_keep = prev_frame->updatee; StgClosure *updatee_bypass = frame->updatee; -#if 0 /* DEBUG */ - fprintf(stderr, "squeezing frame at %p\n", frame); +#if DEBUG + IF_DEBUG(gc, fprintf(stderr, "@@ squeezing frame at %p\n", frame)); + squeezes++; #endif /* Deal with blocking queues. If both updatees have blocked @@ -2858,7 +3368,12 @@ threadSqueezeStack(StgTSO *tso) * slower --SDM */ #if 0 /* do it properly... */ - if (GET_INFO(updatee_bypass) == BLACKHOLE_BQ_info) { +# if (!defined(LAZY_BLACKHOLING)) && defined(DEBUG) +# error Unimplemented lazy BH warning. (KSW 1999-01) +# endif + if (GET_INFO(updatee_bypass) == BLACKHOLE_BQ_info + || GET_INFO(updatee_bypass) == CAF_BLACKHOLE_info + ) { /* Sigh. It has one. Don't lose those threads! */ if (GET_INFO(updatee_keep) == BLACKHOLE_BQ_info) { /* Urgh. Two queues. Merge them. */ @@ -2883,7 +3398,11 @@ threadSqueezeStack(StgTSO *tso) #endif TICK_UPD_SQUEEZED(); - UPD_IND(updatee_bypass, updatee_keep); /* this wakes the threads up */ + /* wasn't there something about update squeezing and ticky to be + * sorted out? oh yes: we aren't counting each enter properly + * in this case. See the log somewhere. KSW 1999-04-21 + */ + UPD_IND_NOLOCK(updatee_bypass, updatee_keep); /* this wakes the threads up */ sp = (P_)frame - 1; /* sp = stuff to slide */ displacement += sizeofW(StgUpdateFrame); @@ -2896,8 +3415,12 @@ threadSqueezeStack(StgTSO *tso) */ if (is_update_frame) { StgBlockingQueue *bh = (StgBlockingQueue *)frame->updatee; - if (bh->header.info != &BLACKHOLE_BQ_info && + if (bh->header.info != &BLACKHOLE_info && + bh->header.info != &BLACKHOLE_BQ_info && bh->header.info != &CAF_BLACKHOLE_info) { +#if (!defined(LAZY_BLACKHOLING)) && defined(DEBUG) + fprintf(stderr,"Unexpected lazy BHing required at 0x%04x\n",(int)bh); +#endif SET_INFO(bh,&BLACKHOLE_info); } } @@ -2917,9 +3440,10 @@ threadSqueezeStack(StgTSO *tso) else next_frame_bottom = tso->sp - 1; -#if 0 /* DEBUG */ - fprintf(stderr, "sliding [%p, %p] by %ld\n", sp, next_frame_bottom, - displacement); +#if DEBUG + IF_DEBUG(gc, + fprintf(stderr, "sliding [%p, %p] by %ld\n", sp, next_frame_bottom, + displacement)) #endif while (sp >= next_frame_bottom) { @@ -2933,8 +3457,16 @@ threadSqueezeStack(StgTSO *tso) tso->sp += displacement; tso->su = prev_frame; +#if DEBUG + IF_DEBUG(gc, + fprintf(stderr, "@@ threadSqueezeStack: squeezed %d update-frames; found %d BHs; found %d update-, %d stop-, %d catch, %d seq-frames\n", + squeezes, bhs, upd_frames, stop_frames, catch_frames, seq_frames)) +#endif } +//@node Pausing a thread, Index, Stack squeezing +//@subsection Pausing a thread + /* ----------------------------------------------------------------------------- * Pausing a thread * @@ -2942,7 +3474,7 @@ threadSqueezeStack(StgTSO *tso) * here. We also take the opportunity to do stack squeezing if it's * turned on. * -------------------------------------------------------------------------- */ - +//@cindex threadPaused void threadPaused(StgTSO *tso) { @@ -2951,3 +3483,97 @@ threadPaused(StgTSO *tso) else threadLazyBlackHole(tso); } + +/* ----------------------------------------------------------------------------- + * Debugging + * -------------------------------------------------------------------------- */ + +#if DEBUG +//@cindex printMutOnceList +void +printMutOnceList(generation *gen) +{ + StgMutClosure *p, *next; + + p = gen->mut_once_list; + next = p->mut_link; + + fprintf(stderr, "@@ Mut once list %p: ", gen->mut_once_list); + for (; p != END_MUT_LIST; p = next, next = p->mut_link) { + fprintf(stderr, "%p (%s), ", + p, info_type((StgClosure *)p)); + } + fputc('\n', stderr); +} + +//@cindex printMutableList +void +printMutableList(generation *gen) +{ + StgMutClosure *p, *next; + + p = gen->mut_list; + next = p->mut_link; + + fprintf(stderr, "@@ Mutable list %p: ", gen->mut_list); + for (; p != END_MUT_LIST; p = next, next = p->mut_link) { + fprintf(stderr, "%p (%s), ", + p, info_type((StgClosure *)p)); + } + fputc('\n', stderr); +} + +//@cindex maybeLarge +static inline rtsBool +maybeLarge(StgClosure *closure) +{ + StgInfoTable *info = get_itbl(closure); + + /* closure types that may be found on the new_large_objects list; + see scavenge_large */ + return (info->type == MUT_ARR_PTRS || + info->type == MUT_ARR_PTRS_FROZEN || + info->type == TSO || + info->type == ARR_WORDS || + info->type == BCO); +} + + +#endif /* DEBUG */ + +//@node Index, , Pausing a thread +//@subsection Index + +//@index +//* GarbageCollect:: @cindex\s-+GarbageCollect +//* MarkRoot:: @cindex\s-+MarkRoot +//* RevertCAFs:: @cindex\s-+RevertCAFs +//* addBlock:: @cindex\s-+addBlock +//* cleanup_weak_ptr_list:: @cindex\s-+cleanup_weak_ptr_list +//* copy:: @cindex\s-+copy +//* copyPart:: @cindex\s-+copyPart +//* evacuate:: @cindex\s-+evacuate +//* evacuate_large:: @cindex\s-+evacuate_large +//* gcCAFs:: @cindex\s-+gcCAFs +//* isAlive:: @cindex\s-+isAlive +//* maybeLarge:: @cindex\s-+maybeLarge +//* mkMutCons:: @cindex\s-+mkMutCons +//* printMutOnceList:: @cindex\s-+printMutOnceList +//* printMutableList:: @cindex\s-+printMutableList +//* relocate_TSO:: @cindex\s-+relocate_TSO +//* scavenge:: @cindex\s-+scavenge +//* scavenge_large:: @cindex\s-+scavenge_large +//* scavenge_mut_once_list:: @cindex\s-+scavenge_mut_once_list +//* scavenge_mutable_list:: @cindex\s-+scavenge_mutable_list +//* scavenge_one:: @cindex\s-+scavenge_one +//* scavenge_srt:: @cindex\s-+scavenge_srt +//* scavenge_stack:: @cindex\s-+scavenge_stack +//* scavenge_static:: @cindex\s-+scavenge_static +//* threadLazyBlackHole:: @cindex\s-+threadLazyBlackHole +//* threadPaused:: @cindex\s-+threadPaused +//* threadSqueezeStack:: @cindex\s-+threadSqueezeStack +//* traverse_weak_ptr_list:: @cindex\s-+traverse_weak_ptr_list +//* upd_evacuee:: @cindex\s-+upd_evacuee +//* zero_mutable_list:: @cindex\s-+zero_mutable_list +//* zero_static_object_list:: @cindex\s-+zero_static_object_list +//@end index