Write out image bitmap inside of image file.
We now create the image bitmap when we generate the image. The image
bitmap is written after the image inside of the image file. This
speeds up dex2oat by making walking the image during heap creation
unnecessary. This should also help memory pressure by enabling the
image bitmap to be swappable.
Bug: 10432288
Change-Id: Idebf459ed15edbb41a7d9b9b353934155bce2f19
diff --git a/compiler/image_test.cc b/compiler/image_test.cc
index dcafc19..6980091 100644
--- a/compiler/image_test.cc
+++ b/compiler/image_test.cc
@@ -85,6 +85,8 @@
ImageHeader image_header;
file->ReadFully(&image_header, sizeof(image_header));
ASSERT_TRUE(image_header.IsValid());
+ ASSERT_GE(image_header.GetImageBitmapOffset(), sizeof(image_header));
+ ASSERT_NE(0U, image_header.GetImageBitmapSize());
gc::Heap* heap = Runtime::Current()->GetHeap();
ASSERT_EQ(1U, heap->GetContinuousSpaces().size());
@@ -136,6 +138,7 @@
ASSERT_TRUE(heap->GetContinuousSpaces()[1]->IsDlMallocSpace());
gc::space::ImageSpace* image_space = heap->GetImageSpace();
+ image_space->VerifyImageAllocations();
byte* image_begin = image_space->Begin();
byte* image_end = image_space->End();
CHECK_EQ(requested_image_base, reinterpret_cast<uintptr_t>(image_begin));
diff --git a/compiler/image_writer.cc b/compiler/image_writer.cc
index 548ea9e..d1859e6 100644
--- a/compiler/image_writer.cc
+++ b/compiler/image_writer.cc
@@ -29,6 +29,7 @@
#include "elf_writer.h"
#include "gc/accounting/card_table-inl.h"
#include "gc/accounting/heap_bitmap.h"
+#include "gc/accounting/space_bitmap-inl.h"
#include "gc/heap.h"
#include "gc/space/large_object_space.h"
#include "gc/space/space-inl.h"
@@ -136,9 +137,12 @@
CalculateNewObjectOffsets(oat_loaded_size, oat_data_offset);
CopyAndFixupObjects();
PatchOatCodeAndMethods();
+ // Record allocations into the image bitmap.
+ RecordImageAllocations();
Thread::Current()->TransitionFromRunnableToSuspended(kNative);
UniquePtr<File> image_file(OS::CreateEmptyFile(image_filename.c_str()));
+ ImageHeader* image_header = reinterpret_cast<ImageHeader*>(image_->Begin());
if (image_file.get() == NULL) {
LOG(ERROR) << "Failed to open image file " << image_filename;
return false;
@@ -147,14 +151,37 @@
PLOG(ERROR) << "Failed to make image file world readable: " << image_filename;
return EXIT_FAILURE;
}
- bool success = image_file->WriteFully(image_->Begin(), image_end_);
- if (!success) {
+
+ // Write out the image.
+ CHECK_EQ(image_end_, image_header->GetImageSize());
+ if (!image_file->WriteFully(image_->Begin(), image_end_)) {
PLOG(ERROR) << "Failed to write image file " << image_filename;
return false;
}
+
+ // Write out the image bitmap at the page aligned start of the image end.
+ CHECK_ALIGNED(image_header->GetImageBitmapOffset(), kPageSize);
+ if (!image_file->Write(reinterpret_cast<char*>(image_bitmap_->Begin()),
+ image_header->GetImageBitmapSize(),
+ image_header->GetImageBitmapOffset())) {
+ PLOG(ERROR) << "Failed to write image file " << image_filename;
+ return false;
+ }
+
return true;
}
+void ImageWriter::RecordImageAllocations() {
+ uint64_t start_time = NanoTime();
+ CHECK(image_bitmap_.get() != nullptr);
+ for (const auto& it : offsets_) {
+ mirror::Object* obj = reinterpret_cast<mirror::Object*>(image_->Begin() + it.second);
+ DCHECK_ALIGNED(obj, kObjectAlignment);
+ image_bitmap_->Set(obj);
+ }
+ LOG(INFO) << "RecordImageAllocations took " << PrettyDuration(NanoTime() - start_time);
+}
+
bool ImageWriter::AllocMemory() {
size_t size = 0;
for (const auto& space : Runtime::Current()->GetHeap()->GetContinuousSpaces()) {
@@ -388,7 +415,7 @@
DCHECK(!spaces.empty());
DCHECK_EQ(0U, image_end_);
- // leave space for the header, but do not write it yet, we need to
+ // Leave space for the header, but do not write it yet, we need to
// know where image_roots is going to end up
image_end_ += RoundUp(sizeof(ImageHeader), 8); // 64-bit-alignment
@@ -406,13 +433,20 @@
self->EndAssertNoThreadSuspension(old);
}
+ // Create the image bitmap.
+ image_bitmap_.reset(gc::accounting::SpaceBitmap::Create("image bitmap", image_->Begin(),
+ image_end_));
const byte* oat_file_begin = image_begin_ + RoundUp(image_end_, kPageSize);
const byte* oat_file_end = oat_file_begin + oat_loaded_size;
oat_data_begin_ = oat_file_begin + oat_data_offset;
const byte* oat_data_end = oat_data_begin_ + oat_file_->Size();
- // return to write header at start of image with future location of image_roots
+ // Return to write header at start of image with future location of image_roots. At this point,
+ // image_end_ is the size of the image (excluding bitmaps).
ImageHeader image_header(reinterpret_cast<uint32_t>(image_begin_),
+ static_cast<uint32_t>(image_end_),
+ RoundUp(image_end_, kPageSize),
+ image_bitmap_->Size(),
reinterpret_cast<uint32_t>(GetImageAddress(image_roots.get())),
oat_file_->GetOatHeader().GetChecksum(),
reinterpret_cast<uint32_t>(oat_file_begin),
diff --git a/compiler/image_writer.h b/compiler/image_writer.h
index 6a126b8..0d85f36 100644
--- a/compiler/image_writer.h
+++ b/compiler/image_writer.h
@@ -58,7 +58,10 @@
private:
bool AllocMemory();
- // we use the lock word to store the offset of the object in the image
+ // Mark the objects defined in this space in the given live bitmap.
+ void RecordImageAllocations() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
+
+ // We use the lock word to store the offset of the object in the image.
void AssignImageOffset(mirror::Object* object)
SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
DCHECK(object != NULL);
@@ -194,6 +197,9 @@
// Beginning target oat address for the pointers from the output image to its oat file.
const byte* oat_data_begin_;
+ // Image bitmap which lets us know where the objects inside of the image reside.
+ UniquePtr<gc::accounting::SpaceBitmap> image_bitmap_;
+
// Offset from oat_data_begin_ to the stubs.
uint32_t interpreter_to_interpreter_bridge_offset_;
uint32_t interpreter_to_compiled_code_bridge_offset_;