Fix region space when used with SetLengthToUsableSizeVisitor.
The region space relies on obj->SizeOf for some of its logic.
By having SetLengthToUsableSizeVisitor "change" the SizeOf
what's being allocated.
The bug happens during RegionSpace::ClearFromSpace: for unevac regions
we iterate over following regions. If LiveBytes != Top() - Begin()
(which happen for large allocations using SetLengthToUsableSizeVisitor),
we break the loop.
The next region to analyze is a large tail, and we see LiveBytes() == 0
(tails apparently always have live bytes == 0), the code is then
happy to release the large tail, even though the large object is still
live.
bug: 37187694
bug: 62889232
Test: 659-unpadded-array
(cherry picked from commit 4b361a87520643c888a3d2c52dffa050fabd7a0b)
(cherry picked from commit 0436bb29ed9f9a2958454a1140259349d1659f2a)
Merged-In: Ia5c156a6969aad0b0c2ea2a4b7a0abdfa4088df6
Change-Id: I3df29d3774aca8d73238324ee6784998f8525b4f
(cherry picked from commit 69ddc6dada4bff237dbe4548b4e0b863bcc39921)
diff --git a/runtime/gc/collector/concurrent_copying.cc b/runtime/gc/collector/concurrent_copying.cc
index ab2146a..0748c7b 100644
--- a/runtime/gc/collector/concurrent_copying.cc
+++ b/runtime/gc/collector/concurrent_copying.cc
@@ -2175,7 +2175,9 @@
// Note that from_ref is a from space ref so the SizeOf() call will access the from-space meta
// objects, but it's ok and necessary.
size_t obj_size = from_ref->SizeOf<kDefaultVerifyFlags>();
- size_t region_space_alloc_size = RoundUp(obj_size, space::RegionSpace::kAlignment);
+ size_t region_space_alloc_size = (obj_size <= space::RegionSpace::kRegionSize)
+ ? RoundUp(obj_size, space::RegionSpace::kAlignment)
+ : RoundUp(obj_size, space::RegionSpace::kRegionSize);
size_t region_space_bytes_allocated = 0U;
size_t non_moving_space_bytes_allocated = 0U;
size_t bytes_allocated = 0U;
diff --git a/runtime/gc/space/region_space-inl.h b/runtime/gc/space/region_space-inl.h
index 3910a03..3a57a81 100644
--- a/runtime/gc/space/region_space-inl.h
+++ b/runtime/gc/space/region_space-inl.h
@@ -315,18 +315,21 @@
DCHECK(first_reg->IsFree());
first_reg->UnfreeLarge(this, time_);
++num_non_free_regions_;
- first_reg->SetTop(first_reg->Begin() + num_bytes);
+ size_t allocated = num_regs * kRegionSize;
+ // We make 'top' all usable bytes, as the caller of this
+ // allocation may use all of 'usable_size' (see mirror::Array::Alloc).
+ first_reg->SetTop(first_reg->Begin() + allocated);
for (size_t p = left + 1; p < right; ++p) {
DCHECK_LT(p, num_regions_);
DCHECK(regions_[p].IsFree());
regions_[p].UnfreeLargeTail(this, time_);
++num_non_free_regions_;
}
- *bytes_allocated = num_bytes;
+ *bytes_allocated = allocated;
if (usable_size != nullptr) {
- *usable_size = num_regs * kRegionSize;
+ *usable_size = allocated;
}
- *bytes_tl_bulk_allocated = num_bytes;
+ *bytes_tl_bulk_allocated = allocated;
return reinterpret_cast<mirror::Object*>(first_reg->Begin());
} else {
// right points to the non-free region. Start with the one after it.
diff --git a/runtime/gc/space/region_space.h b/runtime/gc/space/region_space.h
index 4dea0fa..07aea95 100644
--- a/runtime/gc/space/region_space.h
+++ b/runtime/gc/space/region_space.h
@@ -411,7 +411,9 @@
DCHECK(IsInUnevacFromSpace());
DCHECK(!IsLargeTail());
DCHECK_NE(live_bytes_, static_cast<size_t>(-1));
- live_bytes_ += live_bytes;
+ // For large allocations, we always consider all bytes in the
+ // regions live.
+ live_bytes_ += IsLarge() ? Top() - begin_ : live_bytes;
DCHECK_LE(live_bytes_, BytesAllocated());
}
diff --git a/test/659-unpadded-array/expected.txt b/test/659-unpadded-array/expected.txt
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/test/659-unpadded-array/expected.txt
diff --git a/test/659-unpadded-array/info.txt b/test/659-unpadded-array/info.txt
new file mode 100644
index 0000000..905c529
--- /dev/null
+++ b/test/659-unpadded-array/info.txt
@@ -0,0 +1,3 @@
+Regression test for the concurrent GC whose region space had
+a bug when the request for allocation ended up using 'usable_size'
+instead of the initially requested number of bytes.
diff --git a/test/659-unpadded-array/src/Main.java b/test/659-unpadded-array/src/Main.java
new file mode 100644
index 0000000..80fd6e2
--- /dev/null
+++ b/test/659-unpadded-array/src/Main.java
@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+import dalvik.system.VMRuntime;
+
+public class Main {
+ public static void main(String[] args) {
+ // Call our optimization API, we used to have a bug in the RegionSpace on large
+ // objects allocated through it.
+ Object[] o = (Object[]) VMRuntime.getRuntime().newUnpaddedArray(Object.class, 70000);
+
+ // Make the test run for 30 seconds to be less dependent on GC heuristics.
+ long time = System.currentTimeMillis();
+ int i = 1;
+ do {
+ allocateIntArray(i);
+ for (int j = 0; j < o.length; j++) {
+ if (o[j] != null) {
+ // Just print, not throw, to get into "interesting" issues (eg the first
+ // element that will not be null is the class of the object, the second is
+ // actually the first element of the int array).
+ System.out.println("Unexpected value: " + o[j]);
+ }
+ }
+ if (i < 100000) {
+ i++;
+ } else {
+ i = 0;
+ }
+ } while (System.currentTimeMillis() - time < 30000);
+ }
+
+ static void allocateIntArray(int i) {
+ int[] intArray = new int[i];
+ for (int j = 0; j < intArray.length; j++) {
+ intArray[j] = 1;
+ }
+ }
+}
