--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psPromotionManager.inline.hpp Mon Feb 06 12:18:24 2012 -0800
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psPromotionManager.inline.hpp Fri Feb 10 17:40:20 2012 -0800
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2002, 2012, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -61,6 +61,170 @@
claim_or_forward_internal_depth(p);
}
+//
+// This method is pretty bulky. It would be nice to split it up
+// into smaller submethods, but we need to be careful not to hurt
+// performance.
+//
+template<bool promote_immediately>
+oop PSPromotionManager::copy_to_survivor_space(oop o) {
+ assert(PSScavenge::should_scavenge(&o), "Sanity");
+
+ oop new_obj = NULL;
+
+ // NOTE! We must be very careful with any methods that access the mark
+ // in o. There may be multiple threads racing on it, and it may be forwarded
+ // at any time. Do not use oop methods for accessing the mark!
+ markOop test_mark = o->mark();
+
+ // The same test as "o->is_forwarded()"
+ if (!test_mark->is_marked()) {
+ bool new_obj_is_tenured = false;
+ size_t new_obj_size = o->size();
+
+ if (!promote_immediately) {
+ // Find the objects age, MT safe.
+ int age = (test_mark->has_displaced_mark_helper() /* o->has_displaced_mark() */) ?
+ test_mark->displaced_mark_helper()->age() : test_mark->age();
+
+ // Try allocating obj in to-space (unless too old)
+ if (age < PSScavenge::tenuring_threshold()) {
+ new_obj = (oop) _young_lab.allocate(new_obj_size);
+ if (new_obj == NULL && !_young_gen_is_full) {
+ // Do we allocate directly, or flush and refill?
+ if (new_obj_size > (YoungPLABSize / 2)) {
+ // Allocate this object directly
+ new_obj = (oop)young_space()->cas_allocate(new_obj_size);
+ } else {
+ // Flush and fill
+ _young_lab.flush();
+
+ HeapWord* lab_base = young_space()->cas_allocate(YoungPLABSize);
+ if (lab_base != NULL) {
+ _young_lab.initialize(MemRegion(lab_base, YoungPLABSize));
+ // Try the young lab allocation again.
+ new_obj = (oop) _young_lab.allocate(new_obj_size);
+ } else {
+ _young_gen_is_full = true;
+ }
+ }
+ }
+ }
+ }
+
+ // Otherwise try allocating obj tenured
+ if (new_obj == NULL) {
+#ifndef PRODUCT
+ if (Universe::heap()->promotion_should_fail()) {
+ return oop_promotion_failed(o, test_mark);
+ }
+#endif // #ifndef PRODUCT
+
+ new_obj = (oop) _old_lab.allocate(new_obj_size);
+ new_obj_is_tenured = true;
+
+ if (new_obj == NULL) {
+ if (!_old_gen_is_full) {
+ // Do we allocate directly, or flush and refill?
+ if (new_obj_size > (OldPLABSize / 2)) {
+ // Allocate this object directly
+ new_obj = (oop)old_gen()->cas_allocate(new_obj_size);
+ } else {
+ // Flush and fill
+ _old_lab.flush();
+
+ HeapWord* lab_base = old_gen()->cas_allocate(OldPLABSize);
+ if(lab_base != NULL) {
+ _old_lab.initialize(MemRegion(lab_base, OldPLABSize));
+ // Try the old lab allocation again.
+ new_obj = (oop) _old_lab.allocate(new_obj_size);
+ }
+ }
+ }
+
+ // This is the promotion failed test, and code handling.
+ // The code belongs here for two reasons. It is slightly
+ // different thatn the code below, and cannot share the
+ // CAS testing code. Keeping the code here also minimizes
+ // the impact on the common case fast path code.
+
+ if (new_obj == NULL) {
+ _old_gen_is_full = true;
+ return oop_promotion_failed(o, test_mark);
+ }
+ }
+ }
+
+ assert(new_obj != NULL, "allocation should have succeeded");
+
+ // Copy obj
+ Copy::aligned_disjoint_words((HeapWord*)o, (HeapWord*)new_obj, new_obj_size);
+
+ // Now we have to CAS in the header.
+ if (o->cas_forward_to(new_obj, test_mark)) {
+ // We won any races, we "own" this object.
+ assert(new_obj == o->forwardee(), "Sanity");
+
+ // Increment age if obj still in new generation. Now that
+ // we're dealing with a markOop that cannot change, it is
+ // okay to use the non mt safe oop methods.
+ if (!new_obj_is_tenured) {
+ new_obj->incr_age();
+ assert(young_space()->contains(new_obj), "Attempt to push non-promoted obj");
+ }
+
+ // Do the size comparison first with new_obj_size, which we
+ // already have. Hopefully, only a few objects are larger than
+ // _min_array_size_for_chunking, and most of them will be arrays.
+ // So, the is->objArray() test would be very infrequent.
+ if (new_obj_size > _min_array_size_for_chunking &&
+ new_obj->is_objArray() &&
+ PSChunkLargeArrays) {
+ // we'll chunk it
+ oop* const masked_o = mask_chunked_array_oop(o);
+ push_depth(masked_o);
+ TASKQUEUE_STATS_ONLY(++_arrays_chunked; ++_masked_pushes);
+ } else {
+ // we'll just push its contents
+ new_obj->push_contents(this);
+ }
+ } else {
+ // We lost, someone else "owns" this object
+ guarantee(o->is_forwarded(), "Object must be forwarded if the cas failed.");
+
+ // Try to deallocate the space. If it was directly allocated we cannot
+ // deallocate it, so we have to test. If the deallocation fails,
+ // overwrite with a filler object.
+ if (new_obj_is_tenured) {
+ if (!_old_lab.unallocate_object((HeapWord*) new_obj, new_obj_size)) {
+ CollectedHeap::fill_with_object((HeapWord*) new_obj, new_obj_size);
+ }
+ } else if (!_young_lab.unallocate_object((HeapWord*) new_obj, new_obj_size)) {
+ CollectedHeap::fill_with_object((HeapWord*) new_obj, new_obj_size);
+ }
+
+ // don't update this before the unallocation!
+ new_obj = o->forwardee();
+ }
+ } else {
+ assert(o->is_forwarded(), "Sanity");
+ new_obj = o->forwardee();
+ }
+
+#ifdef DEBUG
+ // This code must come after the CAS test, or it will print incorrect
+ // information.
+ if (TraceScavenge) {
+ gclog_or_tty->print_cr("{%s %s " PTR_FORMAT " -> " PTR_FORMAT " (" SIZE_FORMAT ")}",
+ PSScavenge::should_scavenge(&new_obj) ? "copying" : "tenuring",
+ new_obj->blueprint()->internal_name(), o, new_obj, new_obj->size());
+ }
+#endif
+
+ return new_obj;
+}
+
+
inline void PSPromotionManager::process_popped_location_depth(StarTask p) {
if (is_oop_masked(p)) {
assert(PSChunkLargeArrays, "invariant");
@@ -69,9 +233,9 @@
} else {
if (p.is_narrow()) {
assert(UseCompressedOops, "Error");
- PSScavenge::copy_and_push_safe_barrier(this, (narrowOop*)p);
+ PSScavenge::copy_and_push_safe_barrier<narrowOop, /*promote_immediately=*/false>(this, p);
} else {
- PSScavenge::copy_and_push_safe_barrier(this, (oop*)p);
+ PSScavenge::copy_and_push_safe_barrier<oop, /*promote_immediately=*/false>(this, p);
}
}
}