REGPARM1 static StgClosure * evacuate (StgClosure *q);
static void zero_static_object_list ( StgClosure* first_static );
-static void zero_mutable_list ( StgMutClosure *first );
static rtsBool traverse_weak_ptr_list ( void );
static void mark_weak_ptr_list ( StgWeak **list );
static void scavenge_large ( step * );
static void scavenge_static ( void );
static void scavenge_mutable_list ( generation *g );
-static void scavenge_mut_once_list ( generation *g );
static void scavenge_large_bitmap ( StgPtr p,
StgLargeBitmap *large_bitmap,
(and all younger generations):
- follow all pointers in the root set. the root set includes all
- mutable objects in all generations (mutable_list and mut_once_list).
+ mutable objects in all generations (mutable_list).
- for each pointer, evacuate the object it points to into either
When we evacuate an object we attempt to evacuate
everything it points to into the same generation - this is
achieved by setting evac_gen to the desired generation. If
- we can't do this, then an entry in the mut_once list has to
+ we can't do this, then an entry in the mut list has to
be made for the cross-generation pointer.
+ if the object is already in a generation > N, then leave
static_objects = END_OF_STATIC_LIST;
scavenged_static_objects = END_OF_STATIC_LIST;
- /* zero the mutable list for the oldest generation (see comment by
- * zero_mutable_list below).
- */
- if (major_gc) {
- zero_mutable_list(generations[RtsFlags.GcFlags.generations-1].mut_once_list);
- }
-
/* Save the old to-space if we're doing a two-space collection
*/
if (RtsFlags.GcFlags.generations == 1) {
// collecting.
//
for (g = 0; g <= N; g++) {
- generations[g].mut_once_list = END_MUT_LIST;
- generations[g].mut_list = END_MUT_LIST;
+
+ // throw away the mutable list. Invariant: the mutable list
+ // always has at least one block; this means we can avoid a check for
+ // NULL in recordMutable().
+ if (g != 0) {
+ freeChain(generations[g].mut_list);
+ generations[g].mut_list = allocBlock();
+ }
for (s = 0; s < generations[g].n_steps; s++) {
int st;
for (g = RtsFlags.GcFlags.generations-1; g > N; g--) {
generations[g].saved_mut_list = generations[g].mut_list;
- generations[g].mut_list = END_MUT_LIST;
+ generations[g].mut_list = allocBlock();
+ // mut_list always has at least one block.
}
- // 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--) {
- scavenge(&generations[g].steps[st]);
- }
- }
-
- for (g = RtsFlags.GcFlags.generations-1; g > N; g--) {
- IF_PAR_DEBUG(verbose,
- printMutableList(&generations[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--) {
generations[g].collections++; // for stats
}
+ // Count the mutable list as bytes "copied" for the purposes of
+ // stats. Every mutable list is copied during every GC.
+ if (g > 0) {
+ for (bd = generations[g].mut_list; bd != NULL; bd = bd->link) {
+ copied += (bd->free - bd->start) * sizeof(StgWord);
+ }
+ }
+
for (s = 0; s < generations[g].n_steps; s++) {
bdescr *next;
stp = &generations[g].steps[s];
}
/* -----------------------------------------------------------------------------
- Adding a MUT_CONS to an older generation.
-
- This is necessary from time to time when we end up with an
- old-to-new generation pointer in a non-mutable object. We defer
- the promotion until the next GC.
- -------------------------------------------------------------------------- */
-
-static StgClosure *
-mkMutCons(StgClosure *ptr, generation *gen)
-{
- StgMutVar *q;
- step *stp;
-
- stp = &gen->steps[0];
-
- /* chain a new block onto the to-space for the destination step if
- * necessary.
- */
- if (stp->hp + sizeofW(StgIndOldGen) >= stp->hpLim) {
- gc_alloc_block(stp);
- }
-
- q = (StgMutVar *)stp->hp;
- stp->hp += sizeofW(StgMutVar);
-
- SET_HDR(q,&stg_MUT_CONS_info,CCS_GC);
- q->var = ptr;
- recordOldToNewPtrs((StgMutClosure *)q);
-
- return (StgClosure *)q;
-}
-
-/* -----------------------------------------------------------------------------
Evacuate
This is called (eventually) for every live object in the system.
case FUN_1_0:
case FUN_0_1:
case CONSTR_1_0:
+ case THUNK_1_0:
+ case THUNK_0_1:
return copy(q,sizeofW(StgHeader)+1,stp);
- case THUNK_1_0: // here because of MIN_UPD_SIZE
- case THUNK_0_1:
case THUNK_1_1:
case THUNK_0_2:
case THUNK_2_0:
case MUT_ARR_PTRS:
case MUT_ARR_PTRS_FROZEN:
+ case MUT_ARR_PTRS_FROZEN0:
// just copy the block
return copy(q,mut_arr_ptrs_sizeW((StgMutArrPtrs *)q),stp);
switch (info->type) {
case MVAR:
- /* treat MVars specially, because we don't want to evacuate the
- * mut_link field in the middle of the closure.
- */
{
StgMVar *mvar = ((StgMVar *)p);
evac_gen = 0;
mvar->tail = (StgTSO *)evacuate((StgClosure *)mvar->tail);
mvar->value = evacuate((StgClosure *)mvar->value);
evac_gen = saved_evac_gen;
- recordMutable((StgMutClosure *)mvar);
- failed_to_evac = rtsFalse; // mutable.
+ failed_to_evac = rtsTrue; // mutable.
p += sizeofW(StgMVar);
break;
}
case THUNK_1_0:
scavenge_thunk_srt(info);
((StgClosure *)p)->payload[0] = evacuate(((StgClosure *)p)->payload[0]);
- p += sizeofW(StgHeader) + 2; // MIN_UPD_SIZE
+ p += sizeofW(StgHeader) + 1;
break;
case FUN_1_0:
case THUNK_0_1:
scavenge_thunk_srt(info);
- p += sizeofW(StgHeader) + 2; // MIN_UPD_SIZE
+ p += sizeofW(StgHeader) + 1;
break;
case FUN_0_1:
}
// 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);
+ ((StgInd *)p)->indirectee = evacuate(((StgInd *)p)->indirectee);
+ p += sizeofW(StgInd);
break;
case MUT_VAR:
evac_gen = 0;
((StgMutVar *)p)->var = evacuate(((StgMutVar *)p)->var);
evac_gen = saved_evac_gen;
- recordMutable((StgMutClosure *)p);
- failed_to_evac = rtsFalse; // mutable anyhow
- p += sizeofW(StgMutVar);
- break;
-
- case MUT_CONS:
- // ignore these
- failed_to_evac = rtsFalse; // mutable anyhow
+ failed_to_evac = rtsTrue; // mutable anyhow
p += sizeofW(StgMutVar);
break;
StgBlockingQueue *bh = (StgBlockingQueue *)p;
bh->blocking_queue =
(StgTSO *)evacuate((StgClosure *)bh->blocking_queue);
- recordMutable((StgMutClosure *)bh);
- failed_to_evac = rtsFalse;
+ failed_to_evac = rtsTrue;
p += BLACKHOLE_sizeW();
break;
}
*p = (StgWord)(StgPtr)evacuate((StgClosure *)*p);
}
evac_gen = saved_evac_gen;
- recordMutable((StgMutClosure *)q);
- failed_to_evac = rtsFalse; // mutable anyhow.
+ failed_to_evac = rtsTrue; // mutable anyhow.
break;
}
case MUT_ARR_PTRS_FROZEN:
+ case MUT_ARR_PTRS_FROZEN0:
// follow everything
{
StgPtr next;
- // Set the mut_link field to NULL, so that we will put this
- // array back on the mutable list if it is subsequently thawed
- // by unsafeThaw#.
- ((StgMutArrPtrs*)p)->mut_link = NULL;
-
next = p + mut_arr_ptrs_sizeW((StgMutArrPtrs*)p);
for (p = (P_)((StgMutArrPtrs *)p)->payload; p < next; p++) {
*p = (StgWord)(StgPtr)evacuate((StgClosure *)*p);
evac_gen = 0;
scavengeTSO(tso);
evac_gen = saved_evac_gen;
- recordMutable((StgMutClosure *)tso);
- failed_to_evac = rtsFalse; // mutable anyhow.
+ failed_to_evac = rtsTrue; // mutable anyhow.
p += tso_sizeW(tso);
break;
}
StgRBH *rbh = (StgRBH *)p;
(StgClosure *)rbh->blocking_queue =
evacuate((StgClosure *)rbh->blocking_queue);
- recordMutable((StgMutClosure *)to);
- failed_to_evac = rtsFalse; // mutable anyhow.
+ failed_to_evac = rtsTrue; // mutable anyhow.
IF_DEBUG(gc,
debugBelch("@@ scavenge: RBH %p (%s) (new blocking_queue link=%p)",
p, info_type(p), (StgClosure *)rbh->blocking_queue));
// 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,
debugBelch("@@ scavenge: %p (%s); node is now %p; exciting, isn't it",
bf, info_type((StgClosure *)bf),
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,
debugBelch("@@ scavenge: %p (%s) exciting, isn't it",
p, info_type((StgClosure *)p)));
wq->next_queue_entry = (StgTVarWaitQueue *)evacuate((StgClosure*)wq->next_queue_entry);
wq->prev_queue_entry = (StgTVarWaitQueue *)evacuate((StgClosure*)wq->prev_queue_entry);
evac_gen = saved_evac_gen;
- recordMutable((StgMutClosure *)wq);
- failed_to_evac = rtsFalse; // mutable
+ failed_to_evac = rtsTrue; // mutable
p += sizeofW(StgTVarWaitQueue);
break;
}
tvar->current_value = evacuate((StgClosure*)tvar->current_value);
tvar->first_wait_queue_entry = (StgTVarWaitQueue *)evacuate((StgClosure*)tvar->first_wait_queue_entry);
evac_gen = saved_evac_gen;
- recordMutable((StgMutClosure *)tvar);
- failed_to_evac = rtsFalse; // mutable
+ failed_to_evac = rtsTrue; // mutable
p += sizeofW(StgTVar);
break;
}
trec->enclosing_trec = (StgTRecHeader *)evacuate((StgClosure*)trec->enclosing_trec);
trec->current_chunk = (StgTRecChunk *)evacuate((StgClosure*)trec->current_chunk);
evac_gen = saved_evac_gen;
- recordMutable((StgMutClosure *)trec);
- failed_to_evac = rtsFalse; // mutable
+ failed_to_evac = rtsTrue; // mutable
p += sizeofW(StgTRecHeader);
break;
}
e->new_value = evacuate((StgClosure*)e->new_value);
}
evac_gen = saved_evac_gen;
- recordMutable((StgMutClosure *)tc);
- failed_to_evac = rtsFalse; // mutable
+ failed_to_evac = rtsTrue; // mutable
p += sizeofW(StgTRecChunk);
break;
}
info->type, p);
}
- /* If we didn't manage to promote all the objects pointed to by
- * the current object, then we have to designate this object as
- * mutable (because it contains old-to-new generation pointers).
+ /*
+ * We need to record the current object on the mutable list if
+ * (a) It is actually mutable, or
+ * (b) It contains pointers to a younger generation.
+ * Case (b) arises if we didn't manage to promote everything that
+ * the current object points to into the current generation.
*/
if (failed_to_evac) {
failed_to_evac = rtsFalse;
- mkMutCons((StgClosure *)q, &generations[evac_gen]);
+ recordMutableGen((StgClosure *)q, stp->gen);
}
}
switch (info->type) {
case MVAR:
- /* treat MVars specially, because we don't want to evacuate the
- * mut_link field in the middle of the closure.
- */
{
StgMVar *mvar = ((StgMVar *)p);
evac_gen = 0;
mvar->tail = (StgTSO *)evacuate((StgClosure *)mvar->tail);
mvar->value = evacuate((StgClosure *)mvar->value);
evac_gen = saved_evac_gen;
- failed_to_evac = rtsFalse; // mutable.
+ failed_to_evac = rtsTrue; // mutable.
break;
}
case IND_OLDGEN:
case IND_OLDGEN_PERM:
- ((StgIndOldGen *)p)->indirectee =
- evacuate(((StgIndOldGen *)p)->indirectee);
- if (failed_to_evac) {
- recordOldToNewPtrs((StgMutClosure *)p);
- }
- failed_to_evac = rtsFalse;
+ ((StgInd *)p)->indirectee =
+ evacuate(((StgInd *)p)->indirectee);
break;
case MUT_VAR:
evac_gen = 0;
((StgMutVar *)p)->var = evacuate(((StgMutVar *)p)->var);
evac_gen = saved_evac_gen;
- failed_to_evac = rtsFalse;
- break;
-
- case MUT_CONS:
- // ignore these
- failed_to_evac = rtsFalse;
+ failed_to_evac = rtsTrue;
break;
case CAF_BLACKHOLE:
StgBlockingQueue *bh = (StgBlockingQueue *)p;
bh->blocking_queue =
(StgTSO *)evacuate((StgClosure *)bh->blocking_queue);
- failed_to_evac = rtsFalse;
+ failed_to_evac = rtsTrue;
break;
}
*p = (StgWord)(StgPtr)evacuate((StgClosure *)*p);
}
evac_gen = saved_evac_gen;
- failed_to_evac = rtsFalse; // mutable anyhow.
+ failed_to_evac = rtsTrue; // mutable anyhow.
break;
}
case MUT_ARR_PTRS_FROZEN:
+ case MUT_ARR_PTRS_FROZEN0:
// follow everything
{
StgPtr next;
- // Set the mut_link field to NULL, so that we will put this
- // array on the mutable list if it is subsequently thawed
- // by unsafeThaw#.
- ((StgMutArrPtrs*)p)->mut_link = NULL;
-
next = p + mut_arr_ptrs_sizeW((StgMutArrPtrs*)p);
for (p = (P_)((StgMutArrPtrs *)p)->payload; p < next; p++) {
*p = (StgWord)(StgPtr)evacuate((StgClosure *)*p);
evac_gen = 0;
scavengeTSO(tso);
evac_gen = saved_evac_gen;
- failed_to_evac = rtsFalse;
+ failed_to_evac = rtsTrue;
break;
}
StgRBH *rbh = (StgRBH *)p;
bh->blocking_queue =
(StgTSO *)evacuate((StgClosure *)bh->blocking_queue);
- recordMutable((StgMutClosure *)rbh);
- failed_to_evac = rtsFalse; // mutable anyhow.
+ failed_to_evac = rtsTrue; // mutable anyhow.
IF_DEBUG(gc,
debugBelch("@@ scavenge: RBH %p (%s) (new blocking_queue link=%p)",
p, info_type(p), (StgClosure *)rbh->blocking_queue));
// 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,
debugBelch("@@ scavenge: %p (%s); node is now %p; exciting, isn't it",
bf, info_type((StgClosure *)bf),
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,
debugBelch("@@ scavenge: %p (%s) exciting, isn't it",
p, info_type((StgClosure *)p)));
wq->next_queue_entry = (StgTVarWaitQueue *)evacuate((StgClosure*)wq->next_queue_entry);
wq->prev_queue_entry = (StgTVarWaitQueue *)evacuate((StgClosure*)wq->prev_queue_entry);
evac_gen = saved_evac_gen;
- recordMutable((StgMutClosure *)wq);
- failed_to_evac = rtsFalse; // mutable
+ failed_to_evac = rtsTrue; // mutable
break;
}
tvar->current_value = evacuate((StgClosure*)tvar->current_value);
tvar->first_wait_queue_entry = (StgTVarWaitQueue *)evacuate((StgClosure*)tvar->first_wait_queue_entry);
evac_gen = saved_evac_gen;
- recordMutable((StgMutClosure *)tvar);
- failed_to_evac = rtsFalse; // mutable
+ failed_to_evac = rtsTrue; // mutable
break;
}
e->new_value = evacuate((StgClosure*)e->new_value);
}
evac_gen = saved_evac_gen;
- recordMutable((StgMutClosure *)tc);
- failed_to_evac = rtsFalse; // mutable
+ failed_to_evac = rtsTrue; // mutable
break;
}
trec->enclosing_trec = (StgTRecHeader *)evacuate((StgClosure*)trec->enclosing_trec);
trec->current_chunk = (StgTRecChunk *)evacuate((StgClosure*)trec->current_chunk);
evac_gen = saved_evac_gen;
- recordMutable((StgMutClosure *)trec);
- failed_to_evac = rtsFalse; // mutable
+ failed_to_evac = rtsTrue; // mutable
break;
}
if (failed_to_evac) {
failed_to_evac = rtsFalse;
- mkMutCons((StgClosure *)q, &generations[evac_gen]);
+ recordMutableGen((StgClosure *)q, &generations[evac_gen]);
}
// mark the next bit to indicate "scavenged"
switch (info->type) {
+ case MVAR:
+ {
+ StgMVar *mvar = ((StgMVar *)p);
+ evac_gen = 0;
+ mvar->head = (StgTSO *)evacuate((StgClosure *)mvar->head);
+ mvar->tail = (StgTSO *)evacuate((StgClosure *)mvar->tail);
+ mvar->value = evacuate((StgClosure *)mvar->value);
+ evac_gen = saved_evac_gen;
+ failed_to_evac = rtsTrue; // mutable.
+ break;
+ }
+
case FUN:
case FUN_1_0: // hardly worth specialising these guys
case FUN_0_1:
case WEAK:
case FOREIGN:
case IND_PERM:
- case IND_OLDGEN_PERM:
{
StgPtr q, end;
break;
}
+ case MUT_VAR:
+ evac_gen = 0;
+ ((StgMutVar *)p)->var = evacuate(((StgMutVar *)p)->var);
+ evac_gen = saved_evac_gen;
+ failed_to_evac = rtsTrue; // mutable anyhow
+ break;
+
case CAF_BLACKHOLE:
case SE_CAF_BLACKHOLE:
case SE_BLACKHOLE:
case BLACKHOLE:
break;
+ case BLACKHOLE_BQ:
+ {
+ StgBlockingQueue *bh = (StgBlockingQueue *)p;
+ evac_gen = 0; // repeatedly mutable
+ bh->blocking_queue =
+ (StgTSO *)evacuate((StgClosure *)bh->blocking_queue);
+ failed_to_evac = rtsTrue;
+ break;
+ }
+
case THUNK_SELECTOR:
{
StgSelector *s = (StgSelector *)p;
break;
}
+ case AP_STACK:
+ {
+ StgAP_STACK *ap = (StgAP_STACK *)p;
+
+ ap->fun = evacuate(ap->fun);
+ scavenge_stack((StgPtr)ap->payload, (StgPtr)ap->payload + ap->size);
+ p = (StgPtr)ap->payload + ap->size;
+ break;
+ }
+
+ case PAP:
+ case AP:
+ p = scavenge_PAP((StgPAP *)p);
+ break;
+
case ARR_WORDS:
// nothing to follow
break;
StgPtr next;
evac_gen = 0; // repeatedly mutable
- recordMutable((StgMutClosure *)p);
next = p + mut_arr_ptrs_sizeW((StgMutArrPtrs*)p);
for (p = (P_)((StgMutArrPtrs *)p)->payload; p < next; p++) {
*p = (StgWord)(StgPtr)evacuate((StgClosure *)*p);
}
evac_gen = saved_evac_gen;
- failed_to_evac = rtsFalse;
+ failed_to_evac = rtsTrue;
break;
}
case MUT_ARR_PTRS_FROZEN:
+ case MUT_ARR_PTRS_FROZEN0:
{
// follow everything
StgPtr next;
- // Set the mut_link field to NULL, so that we will put this
- // array on the mutable list if it is subsequently thawed
- // by unsafeThaw#.
- ((StgMutArrPtrs*)p)->mut_link = NULL;
-
next = p + mut_arr_ptrs_sizeW((StgMutArrPtrs*)p);
for (p = (P_)((StgMutArrPtrs *)p)->payload; p < next; p++) {
*p = (StgWord)(StgPtr)evacuate((StgClosure *)*p);
evac_gen = 0; // repeatedly mutable
scavengeTSO(tso);
- recordMutable((StgMutClosure *)tso);
evac_gen = saved_evac_gen;
- failed_to_evac = rtsFalse;
+ failed_to_evac = rtsTrue;
break;
}
- case AP_STACK:
- {
- StgAP_STACK *ap = (StgAP_STACK *)p;
-
- ap->fun = evacuate(ap->fun);
- scavenge_stack((StgPtr)ap->payload, (StgPtr)ap->payload + ap->size);
- p = (StgPtr)ap->payload + ap->size;
+#if defined(PAR)
+ case RBH: // cf. BLACKHOLE_BQ
+ {
+#if 0
+ nat size, ptrs, nonptrs, vhs;
+ char str[80];
+ StgInfoTable *rip = get_closure_info(p, &size, &ptrs, &nonptrs, &vhs, str);
+#endif
+ StgRBH *rbh = (StgRBH *)p;
+ (StgClosure *)rbh->blocking_queue =
+ evacuate((StgClosure *)rbh->blocking_queue);
+ failed_to_evac = rtsTrue; // mutable anyhow.
+ IF_DEBUG(gc,
+ debugBelch("@@ scavenge: RBH %p (%s) (new blocking_queue link=%p)",
+ p, info_type(p), (StgClosure *)rbh->blocking_queue));
+ // ToDo: use size of reverted closure here!
break;
}
- case PAP:
- case AP:
- p = scavenge_PAP((StgPAP *)p);
- break;
-
- case IND_OLDGEN:
- // This might happen if for instance a MUT_CONS was pointing to a
- // THUNK which has since been updated. The IND_OLDGEN will
- // be on the mutable list anyway, so we don't need to do anything
- // here.
+ 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_DEBUG(gc,
+ debugBelch("@@ scavenge: %p (%s); node is now %p; exciting, isn't it",
+ bf, info_type((StgClosure *)bf),
+ bf->node, info_type(bf->node)));
break;
+ }
- default:
- barf("scavenge_one: strange object %d", (int)(info->type));
- }
-
- no_luck = failed_to_evac;
- failed_to_evac = rtsFalse;
- return (no_luck);
-}
-
-/* -----------------------------------------------------------------------------
- Scavenging mutable lists.
+#ifdef DIST
+ case REMOTE_REF:
+#endif
+ case FETCH_ME:
+ break; // nothing to do in this case
- We treat the mutable list of each generation > N (i.e. all the
- generations older than the one being collected) as roots. We also
- remove non-mutable objects from the mutable list at this point.
- -------------------------------------------------------------------------- */
+ case FETCH_ME_BQ: // cf. BLACKHOLE_BQ
+ {
+ StgFetchMeBlockingQueue *fmbq = (StgFetchMeBlockingQueue *)p;
+ (StgClosure *)fmbq->blocking_queue =
+ evacuate((StgClosure *)fmbq->blocking_queue);
+ IF_DEBUG(gc,
+ debugBelch("@@ scavenge: %p (%s) exciting, isn't it",
+ p, info_type((StgClosure *)p)));
+ break;
+ }
+#endif
-static void
-scavenge_mut_once_list(generation *gen)
-{
- const StgInfoTable *info;
- StgMutClosure *p, *next, *new_list;
+ case TVAR_WAIT_QUEUE:
+ {
+ StgTVarWaitQueue *wq = ((StgTVarWaitQueue *) p);
+ evac_gen = 0;
+ wq->waiting_tso = (StgTSO *)evacuate((StgClosure*)wq->waiting_tso);
+ wq->next_queue_entry = (StgTVarWaitQueue *)evacuate((StgClosure*)wq->next_queue_entry);
+ wq->prev_queue_entry = (StgTVarWaitQueue *)evacuate((StgClosure*)wq->prev_queue_entry);
+ evac_gen = saved_evac_gen;
+ failed_to_evac = rtsTrue; // mutable
+ break;
+ }
- p = gen->mut_once_list;
- new_list = END_MUT_LIST;
- next = p->mut_link;
+ case TVAR:
+ {
+ StgTVar *tvar = ((StgTVar *) p);
+ evac_gen = 0;
+ tvar->current_value = evacuate((StgClosure*)tvar->current_value);
+ tvar->first_wait_queue_entry = (StgTVarWaitQueue *)evacuate((StgClosure*)tvar->first_wait_queue_entry);
+ evac_gen = saved_evac_gen;
+ failed_to_evac = rtsTrue; // mutable
+ break;
+ }
- evac_gen = gen->no;
- failed_to_evac = rtsFalse;
+ case TREC_HEADER:
+ {
+ StgTRecHeader *trec = ((StgTRecHeader *) p);
+ evac_gen = 0;
+ trec->enclosing_trec = (StgTRecHeader *)evacuate((StgClosure*)trec->enclosing_trec);
+ trec->current_chunk = (StgTRecChunk *)evacuate((StgClosure*)trec->current_chunk);
+ evac_gen = saved_evac_gen;
+ failed_to_evac = rtsTrue; // mutable
+ break;
+ }
- for (; p != END_MUT_LIST; p = next, next = p->mut_link) {
+ case TREC_CHUNK:
+ {
+ StgWord i;
+ StgTRecChunk *tc = ((StgTRecChunk *) p);
+ TRecEntry *e = &(tc -> entries[0]);
+ evac_gen = 0;
+ tc->prev_chunk = (StgTRecChunk *)evacuate((StgClosure*)tc->prev_chunk);
+ for (i = 0; i < tc -> next_entry_idx; i ++, e++ ) {
+ e->tvar = (StgTVar *)evacuate((StgClosure*)e->tvar);
+ e->expected_value = evacuate((StgClosure*)e->expected_value);
+ e->new_value = evacuate((StgClosure*)e->new_value);
+ }
+ evac_gen = saved_evac_gen;
+ failed_to_evac = rtsTrue; // mutable
+ break;
+ }
- ASSERT(LOOKS_LIKE_CLOSURE_PTR(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:
case IND_OLDGEN_PERM:
case IND_STATIC:
/* Try to pull the indirectee into this generation, so we can
* remove the indirection from the mutable list.
*/
- ((StgIndOldGen *)p)->indirectee =
- evacuate(((StgIndOldGen *)p)->indirectee);
+ ((StgInd *)p)->indirectee = evacuate(((StgInd *)p)->indirectee);
#if 0 && defined(DEBUG)
if (RtsFlags.DebugFlags.gc)
debugBelch("evac IND_OLDGEN: %ld bytes", size * sizeof(W_));
}
#endif
-
- /* failed_to_evac might happen if we've got more than two
- * generations, we're collecting only generation 0, the
- * indirection resides in generation 2 and the indirectee is
- * in generation 1.
- */
- if (failed_to_evac) {
- failed_to_evac = rtsFalse;
- p->mut_link = new_list;
- new_list = p;
- } else {
- /* the mut_link field of an IND_STATIC is overloaded as the
- * static link field too (it just so happens that we don't need
- * both at the same time), so we need to NULL it out when
- * removing this object from the mutable list because the static
- * link fields are all assumed to be NULL before doing a major
- * collection.
- */
- p->mut_link = NULL;
- }
- continue;
-
- case MUT_CONS:
- /* MUT_CONS is a kind of MUT_VAR, except it that we try to remove
- * it from the mutable list if possible by promoting whatever it
- * points to.
- */
- if (scavenge_one((StgPtr)((StgMutVar *)p)->var)) {
- /* didn't manage to promote everything, so put the
- * MUT_CONS back on the list.
- */
- p->mut_link = new_list;
- new_list = p;
- }
- continue;
+ break;
default:
- // shouldn't have anything else on the mutables list
- barf("scavenge_mut_once_list: strange object? %d", (int)(info->type));
- }
- }
+ barf("scavenge_one: strange object %d", (int)(info->type));
+ }
- gen->mut_once_list = new_list;
+ no_luck = failed_to_evac;
+ failed_to_evac = rtsFalse;
+ return (no_luck);
}
+/* -----------------------------------------------------------------------------
+ Scavenging mutable lists.
+
+ We treat the mutable list of each generation > N (i.e. all the
+ generations older than the one being collected) as roots. We also
+ remove non-mutable objects from the mutable list at this point.
+ -------------------------------------------------------------------------- */
static void
scavenge_mutable_list(generation *gen)
{
- const StgInfoTable *info;
- StgMutClosure *p, *next;
-
- p = gen->saved_mut_list;
- next = p->mut_link;
-
- evac_gen = 0;
- failed_to_evac = rtsFalse;
-
- for (; p != END_MUT_LIST; p = next, next = p->mut_link) {
-
- ASSERT(LOOKS_LIKE_CLOSURE_PTR(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:
- // follow everything
- p->mut_link = gen->mut_list;
- gen->mut_list = p;
- {
- StgPtr end, q;
-
- end = (P_)p + mut_arr_ptrs_sizeW((StgMutArrPtrs*)p);
- for (q = (P_)((StgMutArrPtrs *)p)->payload; q < end; q++) {
- *q = (StgWord)(StgPtr)evacuate((StgClosure *)*q);
- }
- continue;
- }
-
- // Happens if a MUT_ARR_PTRS in the old generation is frozen
- case MUT_ARR_PTRS_FROZEN:
- {
- StgPtr end, q;
-
- evac_gen = gen->no;
- end = (P_)p + mut_arr_ptrs_sizeW((StgMutArrPtrs*)p);
- for (q = (P_)((StgMutArrPtrs *)p)->payload; q < end; q++) {
- *q = (StgWord)(StgPtr)evacuate((StgClosure *)*q);
- }
- evac_gen = 0;
- // Set the mut_link field to NULL, so that we will put this
- // array back on the mutable list if it is subsequently thawed
- // by unsafeThaw#.
- p->mut_link = NULL;
- if (failed_to_evac) {
- failed_to_evac = rtsFalse;
- mkMutCons((StgClosure *)p, gen);
- }
- continue;
- }
-
- case MUT_VAR:
- ((StgMutVar *)p)->var = evacuate(((StgMutVar *)p)->var);
- p->mut_link = gen->mut_list;
- gen->mut_list = p;
- continue;
-
- case MVAR:
- {
- StgMVar *mvar = (StgMVar *)p;
- mvar->head = (StgTSO *)evacuate((StgClosure *)mvar->head);
- mvar->tail = (StgTSO *)evacuate((StgClosure *)mvar->tail);
- mvar->value = evacuate((StgClosure *)mvar->value);
- p->mut_link = gen->mut_list;
- gen->mut_list = p;
- continue;
- }
-
- case TSO:
- {
- StgTSO *tso = (StgTSO *)p;
-
- 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
- * above).
- */
- tso->mut_link = gen->mut_list;
- gen->mut_list = (StgMutClosure *)tso;
- continue;
- }
-
- case BLACKHOLE_BQ:
- {
- StgBlockingQueue *bh = (StgBlockingQueue *)p;
- bh->blocking_queue =
- (StgTSO *)evacuate((StgClosure *)bh->blocking_queue);
- p->mut_link = gen->mut_list;
- gen->mut_list = p;
- 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;
- }
-
-#ifdef DIST
- case REMOTE_REF:
- barf("scavenge_mutable_list: REMOTE_REF %d", (int)(info->type));
-#endif
- 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
-
- case TVAR_WAIT_QUEUE:
- {
- StgTVarWaitQueue *wq = ((StgTVarWaitQueue *) p);
- wq->waiting_tso = (StgTSO *)evacuate((StgClosure*)wq->waiting_tso);
- wq->next_queue_entry = (StgTVarWaitQueue *)evacuate((StgClosure*)wq->next_queue_entry);
- wq->prev_queue_entry = (StgTVarWaitQueue *)evacuate((StgClosure*)wq->prev_queue_entry);
- p->mut_link = gen->mut_list;
- gen->mut_list = p;
- continue;
- }
+ bdescr *bd;
+ StgPtr p, q;
- case TVAR:
- {
- StgTVar *tvar = ((StgTVar *) p);
- tvar->current_value = evacuate((StgClosure*)tvar->current_value);
- tvar->first_wait_queue_entry = (StgTVarWaitQueue *)evacuate((StgClosure*)tvar->first_wait_queue_entry);
- p->mut_link = gen->mut_list;
- gen->mut_list = p;
- continue;
- }
+ bd = gen->saved_mut_list;
- case TREC_CHUNK:
- {
- StgWord i;
- StgTRecChunk *tc = ((StgTRecChunk *) p);
- TRecEntry *e = &(tc -> entries[0]);
- tc->prev_chunk = (StgTRecChunk *)evacuate((StgClosure*)tc->prev_chunk);
- for (i = 0; i < tc -> next_entry_idx; i ++, e++ ) {
- e->tvar = (StgTVar *)evacuate((StgClosure*)e->tvar);
- e->expected_value = evacuate((StgClosure*)e->expected_value);
- e->new_value = evacuate((StgClosure*)e->new_value);
+ evac_gen = gen->no;
+ for (; bd != NULL; bd = bd->link) {
+ for (q = bd->start; q < bd->free; q++) {
+ p = (StgPtr)*q;
+ ASSERT(LOOKS_LIKE_CLOSURE_PTR(p));
+ if (scavenge_one(p)) {
+ /* didn't manage to promote everything, so put the
+ * object back on the list.
+ */
+ recordMutableGen((StgClosure *)p,gen);
+ }
}
- p->mut_link = gen->mut_list;
- gen->mut_list = p;
- continue;
- }
-
- case TREC_HEADER:
- {
- StgTRecHeader *trec = ((StgTRecHeader *) p);
- trec->enclosing_trec = (StgTRecHeader *)evacuate((StgClosure*)trec->enclosing_trec);
- trec->current_chunk = (StgTRecChunk *)evacuate((StgClosure*)trec->current_chunk);
- p->mut_link = gen->mut_list;
- gen->mut_list = p;
- continue;
- }
-
- default:
- // shouldn't have anything else on the mutables list
- barf("scavenge_mutable_list: strange object? %d", (int)(info->type));
}
- }
+
+ // free the old mut_list
+ freeChain(gen->saved_mut_list);
+ gen->saved_mut_list = NULL;
}
ind->indirectee = evacuate(ind->indirectee);
/* might fail to evacuate it, in which case we have to pop it
- * back on the mutable list (and take it off the
- * scavenged_static list because the static link and mut link
- * pointers are one and the same).
+ * back on the mutable list of the oldest generation. We
+ * leave it *on* the scavenged_static_objects list, though,
+ * in case we visit this object again.
*/
if (failed_to_evac) {
failed_to_evac = rtsFalse;
- scavenged_static_objects = IND_STATIC_LINK(p);
- ((StgMutClosure *)ind)->mut_link = oldest_gen->mut_once_list;
- oldest_gen->mut_once_list = (StgMutClosure *)ind;
+ recordMutableGen((StgClosure *)p,oldest_gen);
}
break;
}
p = bd->start;
if (scavenge_one(p)) {
- mkMutCons((StgClosure *)p, stp->gen);
+ recordMutableGen((StgClosure *)p, stp->gen);
}
}
}
}
}
-/* This function is only needed because we share the mutable link
- * field with the static link field in an IND_STATIC, so we have to
- * zero the mut_link field before doing a major GC, which needs the
- * static link field.
- *
- * It doesn't do any harm to zero all the mutable link fields on the
- * mutable list.
- */
-
-static void
-zero_mutable_list( StgMutClosure *first )
-{
- StgMutClosure *next, *c;
-
- for (c = first; c != END_MUT_LIST; c = next) {
- next = c->mut_link;
- c->mut_link = NULL;
- }
-}
-
/* -----------------------------------------------------------------------------
Reverting CAFs
-------------------------------------------------------------------------- */
#if DEBUG
void
-printMutOnceList(generation *gen)
-{
- StgMutClosure *p, *next;
-
- p = gen->mut_once_list;
- next = p->mut_link;
-
- debugBelch("@@ Mut once list %p: ", gen->mut_once_list);
- for (; p != END_MUT_LIST; p = next, next = p->mut_link) {
- debugBelch("%p (%s), ",
- p, info_type((StgClosure *)p));
- }
- debugBelch("\n");
-}
-
-void
printMutableList(generation *gen)
{
- StgMutClosure *p, *next;
+ bdescr *bd;
+ StgPtr p;
- p = gen->mut_list;
- next = p->mut_link;
+ debugBelch("@@ Mutable list %p: ", gen->mut_list);
- debugBelch("@@ Mutable list %p: ", gen->mut_list);
- for (; p != END_MUT_LIST; p = next, next = p->mut_link) {
- debugBelch("%p (%s), ",
- p, info_type((StgClosure *)p));
- }
- debugBelch("\n");
+ for (bd = gen->mut_list; bd != NULL; bd = bd->link) {
+ for (p = bd->start; p < bd->free; p++) {
+ debugBelch("%p (%s), ", (void *)*p, info_type((StgClosure *)*p));
+ }
+ }
+ debugBelch("\n");
}
STATIC_INLINE rtsBool
see scavenge_large */
return (info->type == MUT_ARR_PTRS ||
info->type == MUT_ARR_PTRS_FROZEN ||
+ info->type == MUT_ARR_PTRS_FROZEN0 ||
info->type == TSO ||
info->type == ARR_WORDS);
}
projects / ghc-hetmet.git / blobdiff