Remove unnecessary indirection from MemMap.
Avoid plain MemMap pointers being passed around by changing
the MemMap to moveable and return MemMap objects by value.
Previously we could have a valid zero-size MemMap but this
is now forbidden.
MemMap::RemapAtEnd() is changed to avoid the explicit call
to munmap(); mmap() with MAP_FIXED automatically removes
old mappings for overlapping regions.
Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Test: Pixel 2 XL boots.
Test: m test-art-target-gtest
Test: testrunner.py --target --optimizing
Change-Id: I12bd453c26a396edc20eb141bfd4dad20923f170
diff --git a/runtime/indirect_reference_table.cc b/runtime/indirect_reference_table.cc
index 950a54d..098db9f 100644
--- a/runtime/indirect_reference_table.cc
+++ b/runtime/indirect_reference_table.cc
@@ -78,14 +78,19 @@
CHECK_LE(max_count, kMaxTableSizeInBytes / sizeof(IrtEntry));
const size_t table_bytes = max_count * sizeof(IrtEntry);
- table_mem_map_.reset(MemMap::MapAnonymous("indirect ref table", nullptr, table_bytes,
- PROT_READ | PROT_WRITE, false, false, error_msg));
- if (table_mem_map_.get() == nullptr && error_msg->empty()) {
+ table_mem_map_ = MemMap::MapAnonymous("indirect ref table",
+ /* addr */ nullptr,
+ table_bytes,
+ PROT_READ | PROT_WRITE,
+ /* low_4gb */ false,
+ /* reuse */ false,
+ error_msg);
+ if (!table_mem_map_.IsValid() && error_msg->empty()) {
*error_msg = "Unable to map memory for indirect ref table";
}
- if (table_mem_map_.get() != nullptr) {
- table_ = reinterpret_cast<IrtEntry*>(table_mem_map_->Begin());
+ if (table_mem_map_.IsValid()) {
+ table_ = reinterpret_cast<IrtEntry*>(table_mem_map_.Begin());
} else {
table_ = nullptr;
}
@@ -125,7 +130,7 @@
}
bool IndirectReferenceTable::IsValid() const {
- return table_mem_map_.get() != nullptr;
+ return table_mem_map_.IsValid();
}
// Holes:
@@ -217,20 +222,20 @@
// Note: the above check also ensures that there is no overflow below.
const size_t table_bytes = new_size * sizeof(IrtEntry);
- std::unique_ptr<MemMap> new_map(MemMap::MapAnonymous("indirect ref table",
- nullptr,
- table_bytes,
- PROT_READ | PROT_WRITE,
- false,
- false,
- error_msg));
- if (new_map == nullptr) {
+ MemMap new_map = MemMap::MapAnonymous("indirect ref table",
+ /* addr */ nullptr,
+ table_bytes,
+ PROT_READ | PROT_WRITE,
+ /* is_low_4gb */ false,
+ /* reuse */ false,
+ error_msg);
+ if (!new_map.IsValid()) {
return false;
}
- memcpy(new_map->Begin(), table_mem_map_->Begin(), table_mem_map_->Size());
+ memcpy(new_map.Begin(), table_mem_map_.Begin(), table_mem_map_.Size());
table_mem_map_ = std::move(new_map);
- table_ = reinterpret_cast<IrtEntry*>(table_mem_map_->Begin());
+ table_ = reinterpret_cast<IrtEntry*>(table_mem_map_.Begin());
max_entries_ = new_size;
return true;
@@ -444,7 +449,7 @@
ScopedTrace trace(__PRETTY_FUNCTION__);
const size_t top_index = Capacity();
auto* release_start = AlignUp(reinterpret_cast<uint8_t*>(&table_[top_index]), kPageSize);
- uint8_t* release_end = table_mem_map_->End();
+ uint8_t* release_end = table_mem_map_.End();
madvise(release_start, release_end - release_start, MADV_DONTNEED);
}