/* -----------------------------------------------------------------------------
- * $Id: GC.c,v 1.52 1999/03/15 16:53:11 simonm Exp $
+ * $Id: GC.c,v 1.72 2000/01/22 18:00:03 simonmar Exp $
*
* (c) The GHC Team 1998-1999
*
*
* ---------------------------------------------------------------------------*/
+//@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"
#include "GC.h"
#include "BlockAlloc.h"
#include "Main.h"
-#include "DebugProf.h"
+#include "ProfHeap.h"
#include "SchedAPI.h"
#include "Weak.h"
#include "StablePriv.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.
*
* During GC:
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
-------------------------------------------------------------------------- */
static void gcCAFs ( void );
#endif
+//@node Garbage Collect, Weak Pointers, Static function declarations
+//@subsection Garbage Collect
+
/* -----------------------------------------------------------------------------
GarbageCollect
- free from-space in each step, and set from-space = to-space.
-------------------------------------------------------------------------- */
+//@cindex GarbageCollect
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();
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
*/
major_gc = (N == RtsFlags.GcFlags.generations-1);
/* check stack sanity *before* GC (ToDo: check all threads) */
- /*IF_DEBUG(sanity, checkTSO(MainTSO,0)); */
- IF_DEBUG(sanity, checkFreeListSanity());
+#if defined(GRAN)
+ // ToDo!: check sanity IF_DEBUG(sanity, checkTSOsSanity());
+#endif
+ IF_DEBUG(sanity, checkFreeListSanity());
/* Initialise the static object lists
*/
/* 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--) {
}
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--) {
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.
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();
/* 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();
+
+#if defined(PAR)
+ /* Reconstruct the Global Address tables used in GUM */
+ RebuildGAtables(major_gc);
+#endif
/* start any pending finalizers */
scheduleFinalizers(old_weak_ptr_list);
/* restore enclosing cost centre */
#ifdef PROFILING
+ heapCensus();
CCCS = prev_CCS;
#endif
stat_endGC(allocated, collected, live, copied, N);
}
+//@node Weak Pointers, Evacuation, Garbage Collect
+//@subsection Weak Pointers
+
/* -----------------------------------------------------------------------------
Weak Pointers
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)
evacuated need to be evacuated now.
-------------------------------------------------------------------------- */
+//@cindex cleanup_weak_ptr_list
+
static void
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;
while (1) {
* for static closures with an empty SRT or CONSTR_STATIC_NOCAFs.
*/
+#if 1 || !defined(PAR)
/* ignore closures in generations that we're not collecting. */
+ /* In GUM we use this routine when rebuilding GA tables; for some
+ reason it has problems with the LOOKS_LIKE_STATIC macro -- HWL */
if (LOOKS_LIKE_STATIC(p) || Bdescr((P_)p)->gen->no > N) {
return p;
}
+#endif
switch (info->type) {
}
}
+//@cindex MarkRoot
StgClosure *
MarkRoot(StgClosure *root)
{
return evacuate(root);
}
+//@cindex addBlock
static void addBlock(step *step)
{
bdescr *bd = allocBlock();
new_blocks++;
}
+//@cindex upd_evacuee
+
static __inline__ void
upd_evacuee(StgClosure *p, StgClosure *dest)
{
((StgEvacuated *)p)->evacuee = dest;
}
+//@cindex copy
+
static __inline__ StgClosure *
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)
{
return (StgClosure *)dest;
}
+//@node Evacuation, Scavenging, Weak Pointers
+//@subsection Evacuation
+
/* -----------------------------------------------------------------------------
Evacuate a large object
evacuated, or 0 otherwise.
-------------------------------------------------------------------------- */
+//@cindex evacuate_large
+
static inline void
evacuate_large(StgPtr p, rtsBool mutable)
{
the promotion until the next GC.
-------------------------------------------------------------------------- */
+//@cindex mkMutCons
+
static StgClosure *
mkMutCons(StgClosure *ptr, generation *gen)
{
didn't manage to evacuate this object into evac_gen.
-------------------------------------------------------------------------- */
-
+//@cindex evacuate
static StgClosure *
evacuate(StgClosure *q)
}
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);
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);
/* 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);
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:
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();
}
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->whatNext == 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_)) {
}
}
+#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");
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)
break;
default:
- barf("relocate_TSO");
+ barf("relocate_TSO %d", (int)(get_itbl(su)->type));
}
break;
}
return dest;
}
+//@node Scavenging, Reverting CAFs, Evacuation
+//@subsection Scavenging
+
+//@cindex scavenge_srt
+
static inline void
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
+#ifdef ENABLE_WIN32_DLL_SUPPORT
if ( stgCast(unsigned long,*srt) & 0x1 ) {
evacuate(*stgCast(StgClosure**,(stgCast(unsigned long, *srt) & ~0x1)));
} else {
}
/* -----------------------------------------------------------------------------
+ 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) {
+ 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.
scavenging a mutable object where early promotion isn't such a good
idea.
-------------------------------------------------------------------------- */
-
+//@cindex scavenge
static void
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:
case WEAK:
case FOREIGN:
case STABLE_NAME:
- case IND_PERM:
- case IND_OLDGEN_PERM:
- case CAF_UNENTERED:
{
StgPtr end;
break;
}
+ case IND_PERM:
+ if (step->gen->no != 0) {
+ SET_INFO(((StgClosure *)p), &IND_OLDGEN_PERM_info);
+ }
+ /* fall through */
+ case IND_OLDGEN_PERM:
+ ((StgIndOldGen *)p)->indirectee =
+ evacuate(((StgIndOldGen *)p)->indirectee);
+ if (failed_to_evac) {
+ failed_to_evac = rtsFalse;
+ recordOldToNewPtrs((StgMutClosure *)p);
+ }
+ p += sizeofW(StgIndOldGen);
+ break;
+
+ case CAF_UNENTERED:
+ {
+ StgCAF *caf = (StgCAF *)p;
+
+ caf->body = evacuate(caf->body);
+ if (failed_to_evac) {
+ failed_to_evac = rtsFalse;
+ recordOldToNewPtrs((StgMutClosure *)p);
+ } else {
+ caf->mut_link = NULL;
+ }
+ p += sizeofW(StgCAF);
+ break;
+ }
+
case CAF_ENTERED:
{
StgCAF *caf = (StgCAF *)p;
if (failed_to_evac) {
failed_to_evac = rtsFalse;
recordOldToNewPtrs((StgMutClosure *)p);
+ } else {
+ caf->mut_link = NULL;
}
p += sizeofW(StgCAF);
break;
break;
case CAF_BLACKHOLE:
+ case SE_CAF_BLACKHOLE:
+ case SE_BLACKHOLE:
case BLACKHOLE:
p += BLACKHOLE_sizeW();
break;
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);
- /* 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");
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))
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:
}
case CAF_BLACKHOLE:
+ case SE_CAF_BLACKHOLE:
+ case SE_BLACKHOLE:
case BLACKHOLE:
break;
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;
|| 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:
((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
*/
failed_to_evac = rtsFalse;
p->mut_link = new_list;
new_list = p;
+ } else {
+ p->mut_link = NULL;
}
}
continue;
failed_to_evac = rtsFalse;
p->mut_link = new_list;
new_list = p;
- }
+ } else {
+ p->mut_link = NULL;
+ }
}
continue;
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;
|| 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:
{
StgPtr end, q;
+ IF_DEBUG(gc,
+ belch("@@ scavenge_mut_list: scavenging MUT_ARR_PTRS_FROZEN %p; size: %#x ; next: %p",
+ p, mut_arr_ptrs_sizeW((StgMutArrPtrs*)p), p->mut_link));
+
end = (P_)p + mut_arr_ptrs_sizeW((StgMutArrPtrs*)p);
evac_gen = gen->no;
for (q = (P_)((StgMutArrPtrs *)p)->payload; q < end; q++) {
{
StgPtr end, q;
+ IF_DEBUG(gc,
+ belch("@@ scavenge_mut_list: scavenging MUT_ARR_PTRS %p; size: %#x ; next: %p",
+ p, mut_arr_ptrs_sizeW((StgMutArrPtrs*)p), p->mut_link));
+
end = (P_)p + mut_arr_ptrs_sizeW((StgMutArrPtrs*)p);
for (q = (P_)((StgMutArrPtrs *)p)->payload; q < end; q++) {
(StgClosure *)*q = evacuate((StgClosure *)*q);
* it from the mutable list if possible by promoting whatever it
* points to.
*/
+ IF_DEBUG(gc,
+ belch("@@ scavenge_mut_list: scavenging MUT_VAR %p; var: %p ; next: %p",
+ p, ((StgMutVar *)p)->var, p->mut_link));
+
ASSERT(p->header.info != &MUT_CONS_info);
((StgMutVar *)p)->var = evacuate(((StgMutVar *)p)->var);
p->mut_link = gen->mut_list;
case MVAR:
{
StgMVar *mvar = (StgMVar *)p;
+
+ IF_DEBUG(gc,
+ belch("@@ scavenge_mut_list: scavenging MAVR %p; head: %p; tail: %p; value: %p ; next: %p",
+ mvar, mvar->head, mvar->tail, mvar->value, p->mut_link));
+
(StgClosure *)mvar->head = evacuate((StgClosure *)mvar->head);
(StgClosure *)mvar->tail = evacuate((StgClosure *)mvar->tail);
(StgClosure *)mvar->value = evacuate((StgClosure *)mvar->value);
}
case TSO:
- /* follow ptrs and remove this from the mutable list */
{
StgTSO *tso = (StgTSO *)p;
- /* Don't bother scavenging if this thread is dead
- */
- if (!(tso->whatNext == ThreadComplete ||
- tso->whatNext == ThreadKilled)) {
- /* Don't need to chase the link field for any TSOs on the
- * same queue. Just scavenge this thread's stack
- */
- 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
case BLACKHOLE_BQ:
{
StgBlockingQueue *bh = (StgBlockingQueue *)p;
+
+ IF_DEBUG(gc,
+ belch("@@ scavenge_mut_list: scavenging BLACKHOLE_BQ (%p); next: %p",
+ p, p->mut_link));
+
(StgClosure *)bh->blocking_queue =
evacuate((StgClosure *)bh->blocking_queue);
p->mut_link = gen->mut_list;
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;
+
+ // HWL: old PAR code deleted here
+
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)
{
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))));
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)
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
*/
while (p < stack_end) {
- q = *stgCast(StgPtr*,p);
+ q = *(P_ *)p;
/* If we've got a tag, skip over that many words on the stack */
- if (IS_ARG_TAG(stgCast(StgWord,q))) {
+ if (IS_ARG_TAG((W_)q)) {
p += ARG_SIZE(q);
p++; continue;
}
/* 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)));
* record. All activation records have 'bitmap' style layout
* info.
*/
- info = get_itbl(stgCast(StgClosure*,p));
+ info = get_itbl((StgClosure *)p);
switch (info->type) {
/* Dynamic bitmap: the mask is stored on the stack */
case RET_DYN:
- bitmap = stgCast(StgRetDyn*,p)->liveness;
- p = &payloadWord(stgCast(StgRetDyn*,p),0);
+ bitmap = ((StgRetDyn *)p)->liveness;
+ p = (P_)&((StgRetDyn *)p)->payload[0];
goto small_bitmap;
/* 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,
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:
+ {
+ // StgPtr old_p = p; // debugging only -- HWL
+ /* stack frames like these are ordinary closures and therefore may
+ contain setup-specific fixed-header words (as in GranSim!);
+ therefore, these cases should not use p++ but &(p->payload) -- HWL */
+ // IF_DEBUG(gran, IF_DEBUG(sanity, printObj(p)));
+ bitmap = info->layout.bitmap;
+
+ p = (StgPtr)&(((StgClosure *)p)->payload);
+ // IF_DEBUG(sanity, belch("HWL: scavenge_stack: (STOP|CATCH|SEQ)_FRAME adjusting p from %p to %p (instead of %p)", old_p, p, old_p+1));
+ goto small_bitmap;
+ }
+ 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) {
objects are (repeatedly) mutable, so most of the time evac_gen will
be zero.
--------------------------------------------------------------------------- */
+//@cindex scavenge_large
static void
scavenge_large(step *step)
}
case TSO:
- {
- StgTSO *tso;
-
- tso = (StgTSO *)p;
- /* chase the link field for any TSOs on the same queue */
- (StgClosure *)tso->link = evacuate((StgClosure *)tso->link);
- /* scavenge this thread's stack */
- scavenge_stack(tso->sp, &(tso->stack[tso->stack_size]));
+ scavengeTSO((StgTSO *)p);
+ // HWL: old PAR code deleted here
continue;
- }
default:
barf("scavenge_large: unknown/strange object");
}
}
+//@cindex zero_static_object_list
+
static void
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 )
{
}
}
+//@node Reverting CAFs, Sanity code for CAF garbage collection, Scavenging
+//@subsection Reverting CAFs
+
/* -----------------------------------------------------------------------------
Reverting CAFs
-------------------------------------------------------------------------- */
+//@cindex RevertCAFs
void RevertCAFs(void)
{
enteredCAFs = END_CAF_LIST;
}
+//@cindex revert_dead_CAFs
+
void revert_dead_CAFs(void)
{
StgCAF* caf = enteredCAFs;
new->link = enteredCAFs;
enteredCAFs = new;
} else {
- ASSERT(0);
+ /* ASSERT(0); */
SET_INFO(caf,&CAF_UNENTERED_info);
caf->value = (StgClosure*)0xdeadbeef;
caf->link = (StgCAF*)0xdeadbeef;
}
}
+//@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.
-------------------------------------------------------------------------- */
#ifdef DEBUG
+//@cindex gcCAFs
+
static void
gcCAFs(void)
{
}
#endif
+//@node Lazy black holing, Stack squeezing, Sanity code for CAF garbage collection
+//@subsection Lazy black holing
+
/* -----------------------------------------------------------------------------
Lazy black holing.
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)
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);
}
}
}
+//@node Stack squeezing, Pausing a thread, Lazy black holing
+//@subsection Stack squeezing
+
/* -----------------------------------------------------------------------------
* Stack squeezing
*
* lazy black holing here.
*
* -------------------------------------------------------------------------- */
+//@cindex threadSqueezeStack
static void
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;
*/
next_frame = NULL;
- while ((P_)frame < bottom - 1) { /* bottom - 1 is the STOP_FRAME */
+ /* bottom - sizeof(StgStopFrame) is the STOP_FRAME */
+ while ((P_)frame < bottom - sizeofW(StgStopFrame)) {
prev_frame = frame->link;
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;
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
* 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. */
#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);
*/
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);
}
}
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) {
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
*
* here. We also take the opportunity to do stack squeezing if it's
* turned on.
* -------------------------------------------------------------------------- */
+//@cindex threadPaused
void
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->saved_mut_list;
+ next = p->mut_link;
+
+ fprintf(stderr, "@@ Mutable list %p: ", gen->saved_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);
+}
+#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
+//* mkMutCons:: @cindex\s-+mkMutCons
+//* relocate_TSO:: @cindex\s-+relocate_TSO
+//* revert_dead_CAFs:: @cindex\s-+revert_dead_CAFs
+//* 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
projects / ghc-hetmet.git / blobdiff