Fix race with LOS Begin() and End()
There was a race for the first large object allocation that cause
callers of Begin() and End() to see a null End() and non-null
Begin(). The fix is to hold the lock and get both Begin() and End().
Bug: 32387879
Test: test-art-host CC
Change-Id: I6173bf3a55d3ba017ffa5b5e9f566025c65b7555
diff --git a/runtime/gc/space/large_object_space.cc b/runtime/gc/space/large_object_space.cc
index 2d5d7cb..e71a397 100644
--- a/runtime/gc/space/large_object_space.cc
+++ b/runtime/gc/space/large_object_space.cc
@@ -606,9 +606,12 @@
std::swap(live_bitmap, mark_bitmap);
}
AllocSpace::SweepCallbackContext scc(swap_bitmaps, this);
+ std::pair<uint8_t*, uint8_t*> range = GetBeginEndAtomic();
accounting::LargeObjectBitmap::SweepWalk(*live_bitmap, *mark_bitmap,
- reinterpret_cast<uintptr_t>(Begin()),
- reinterpret_cast<uintptr_t>(End()), SweepCallback, &scc);
+ reinterpret_cast<uintptr_t>(range.first),
+ reinterpret_cast<uintptr_t>(range.second),
+ SweepCallback,
+ &scc);
return scc.freed;
}
@@ -617,6 +620,16 @@
UNIMPLEMENTED(FATAL);
}
+std::pair<uint8_t*, uint8_t*> LargeObjectMapSpace::GetBeginEndAtomic() const {
+ MutexLock mu(Thread::Current(), lock_);
+ return std::make_pair(Begin(), End());
+}
+
+std::pair<uint8_t*, uint8_t*> FreeListSpace::GetBeginEndAtomic() const {
+ MutexLock mu(Thread::Current(), lock_);
+ return std::make_pair(Begin(), End());
+}
+
} // namespace space
} // namespace gc
} // namespace art