GC clean up.
Greater use of directories and namespaces.
Fix bugs that cause verify options to fail.
Address numerous other issues:
GC barrier wait occurring holding locks:
GC barrier waits occur when we wait for threads to run the check point function
on themselves. This is happening with the heap bitmap and mutator lock held
meaning that a thread that tries to take either lock exclusively will block
waiting on a thread that is waiting. If this thread is the thread we're waiting
to run the check point then the VM will deadlock.
This deadlock occurred unnoticed as the call to check for wait safety was
removed in: https://googleplex-android-review.googlesource.com/#/c/249423/1.
NewTimingLogger:
Existing timing log states when a split ends but not when it begins. This isn't
good for systrace, in the context of GC it means that races between mutators
and the GC are hard to discover what phase the GC is in, we know what phase it
just finished and derive but that's not ideal.
Support for only 1 discontinuous space:
Code special cases continuous and large object space, rather than assuming we
can have a collection of both.
Sorted atomic stacks:
Used to improve verification performance. Simplify their use and add extra
checks.
Simplify mod-union table abstractions.
Reduce use of std::strings and their associated overhead in hot code.
Make time units of fields explicit.
Reduce confusion that IsAllocSpace is really IsDlMallocSpace.
Make GetTotalMemory (exposed via System) equal to the footprint (as in Dalvik)
rather than the max memory footprint.
Change-Id: Ie87067140fa4499b15edab691fe6565d79599812
diff --git a/src/gc/accounting/space_bitmap-inl.h b/src/gc/accounting/space_bitmap-inl.h
new file mode 100644
index 0000000..a4fd330
--- /dev/null
+++ b/src/gc/accounting/space_bitmap-inl.h
@@ -0,0 +1,147 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ART_SRC_GC_ACCOUNTING_SPACE_BITMAP_INL_H_
+#define ART_SRC_GC_ACCOUNTING_SPACE_BITMAP_INL_H_
+
+#include "base/logging.h"
+#include "cutils/atomic-inline.h"
+#include "utils.h"
+
+namespace art {
+namespace gc {
+namespace accounting {
+
+inline bool SpaceBitmap::AtomicTestAndSet(const mirror::Object* obj) {
+ uintptr_t addr = reinterpret_cast<uintptr_t>(obj);
+ DCHECK_GE(addr, heap_begin_);
+ const uintptr_t offset = addr - heap_begin_;
+ const size_t index = OffsetToIndex(offset);
+ const word mask = OffsetToMask(offset);
+ word* const address = &bitmap_begin_[index];
+ DCHECK_LT(index, bitmap_size_ / kWordSize) << " bitmap_size_ = " << bitmap_size_;
+ word old_word;
+ do {
+ old_word = *address;
+ // Fast path: The bit is already set.
+ if ((old_word & mask) != 0) {
+ return true;
+ }
+ } while (UNLIKELY(android_atomic_cas(old_word, old_word | mask, address) != 0));
+ return false;
+}
+
+inline bool SpaceBitmap::Test(const mirror::Object* obj) const {
+ uintptr_t addr = reinterpret_cast<uintptr_t>(obj);
+ DCHECK(HasAddress(obj)) << obj;
+ DCHECK(bitmap_begin_ != NULL);
+ DCHECK_GE(addr, heap_begin_);
+ const uintptr_t offset = addr - heap_begin_;
+ return (bitmap_begin_[OffsetToIndex(offset)] & OffsetToMask(offset)) != 0;
+}
+
+template <typename Visitor, typename FingerVisitor>
+void SpaceBitmap::VisitMarkedRange(uintptr_t visit_begin, uintptr_t visit_end,
+ const Visitor& visitor,
+ const FingerVisitor& finger_visitor) const {
+ DCHECK_LT(visit_begin, visit_end);
+
+ const size_t word_span = kAlignment * kBitsPerWord; // Equals IndexToOffset(1).
+ const size_t bit_index_start = (visit_begin - heap_begin_) / kAlignment;
+ const size_t bit_index_end = (visit_end - heap_begin_ - 1) / kAlignment;
+
+ size_t word_start = bit_index_start / kBitsPerWord;
+ size_t word_end = bit_index_end / kBitsPerWord;
+ DCHECK_LT(word_end * kWordSize, Size());
+
+ // Trim off left_bits of left bits.
+ size_t edge_word = bitmap_begin_[word_start];
+
+ // Handle bits on the left first as a special case
+ size_t left_bits = bit_index_start & (kBitsPerWord - 1);
+ if (left_bits != 0) {
+ edge_word &= (1 << (kBitsPerWord - left_bits)) - 1;
+ }
+
+ // If word_start == word_end then handle this case at the same place we handle the right edge.
+ if (edge_word != 0 && word_start < word_end) {
+ uintptr_t ptr_base = IndexToOffset(word_start) + heap_begin_;
+ finger_visitor(reinterpret_cast<void*>(ptr_base + word_span));
+ do {
+ const size_t shift = CLZ(edge_word);
+ mirror::Object* obj = reinterpret_cast<mirror::Object*>(ptr_base + shift * kAlignment);
+ visitor(obj);
+ edge_word ^= static_cast<size_t>(kWordHighBitMask) >> shift;
+ } while (edge_word != 0);
+ }
+ word_start++;
+
+ for (size_t i = word_start; i < word_end; i++) {
+ size_t w = bitmap_begin_[i];
+ if (w != 0) {
+ uintptr_t ptr_base = IndexToOffset(i) + heap_begin_;
+ finger_visitor(reinterpret_cast<void*>(ptr_base + word_span));
+ do {
+ const size_t shift = CLZ(w);
+ mirror::Object* obj = reinterpret_cast<mirror::Object*>(ptr_base + shift * kAlignment);
+ visitor(obj);
+ w ^= static_cast<size_t>(kWordHighBitMask) >> shift;
+ } while (w != 0);
+ }
+ }
+
+ // Handle the right edge, and also the left edge if both edges are on the same word.
+ size_t right_bits = bit_index_end & (kBitsPerWord - 1);
+
+ // If word_start == word_end then we need to use the word which we removed the left bits.
+ if (word_start <= word_end) {
+ edge_word = bitmap_begin_[word_end];
+ }
+
+ // Bits that we trim off the right.
+ edge_word &= ~((static_cast<size_t>(kWordHighBitMask) >> right_bits) - 1);
+ uintptr_t ptr_base = IndexToOffset(word_end) + heap_begin_;
+ finger_visitor(reinterpret_cast<void*>(ptr_base + word_span));
+ while (edge_word != 0) {
+ const size_t shift = CLZ(edge_word);
+ mirror::Object* obj = reinterpret_cast<mirror::Object*>(ptr_base + shift * kAlignment);
+ visitor(obj);
+ edge_word ^= static_cast<size_t>(kWordHighBitMask) >> shift;
+ }
+}
+
+inline bool SpaceBitmap::Modify(const mirror::Object* obj, bool do_set) {
+ uintptr_t addr = reinterpret_cast<uintptr_t>(obj);
+ DCHECK_GE(addr, heap_begin_);
+ const uintptr_t offset = addr - heap_begin_;
+ const size_t index = OffsetToIndex(offset);
+ const word mask = OffsetToMask(offset);
+ DCHECK_LT(index, bitmap_size_ / kWordSize) << " bitmap_size_ = " << bitmap_size_;
+ word* address = &bitmap_begin_[index];
+ word old_word = *address;
+ if (do_set) {
+ *address = old_word | mask;
+ } else {
+ *address = old_word & ~mask;
+ }
+ return (old_word & mask) != 0;
+}
+
+} // namespace accounting
+} // namespace gc
+} // namespace art
+
+#endif // ART_SRC_GC_ACCOUNTING_SPACE_BITMAP_INL_H_