diff options
| -rw-r--r-- | libartbase/base/allocator.cc | 4 | ||||
| -rw-r--r-- | libartbase/base/allocator.h | 16 |
2 files changed, 12 insertions, 8 deletions
diff --git a/libartbase/base/allocator.cc b/libartbase/base/allocator.cc index 17da789b36..c7be4e0161 100644 --- a/libartbase/base/allocator.cc +++ b/libartbase/base/allocator.cc @@ -76,7 +76,7 @@ namespace TrackedAllocators { // These globals are safe since they don't have any non-trivial destructors. Atomic<size_t> g_bytes_used[kAllocatorTagCount]; -volatile size_t g_max_bytes_used[kAllocatorTagCount]; +Atomic<size_t> g_max_bytes_used[kAllocatorTagCount]; Atomic<uint64_t> g_total_bytes_used[kAllocatorTagCount]; void Dump(std::ostream& os) { @@ -84,7 +84,7 @@ void Dump(std::ostream& os) { os << "Dumping native memory usage\n"; for (size_t i = 0; i < kAllocatorTagCount; ++i) { uint64_t bytes_used = g_bytes_used[i].load(std::memory_order_relaxed); - uint64_t max_bytes_used = g_max_bytes_used[i]; + uint64_t max_bytes_used = g_max_bytes_used[i].load(std::memory_order_relaxed); uint64_t total_bytes_used = g_total_bytes_used[i].load(std::memory_order_relaxed); if (total_bytes_used != 0) { os << static_cast<AllocatorTag>(i) << " active=" << bytes_used << " max=" diff --git a/libartbase/base/allocator.h b/libartbase/base/allocator.h index 7ddbacf716..662f78e448 100644 --- a/libartbase/base/allocator.h +++ b/libartbase/base/allocator.h @@ -71,12 +71,14 @@ std::ostream& operator<<(std::ostream& os, const AllocatorTag& tag); namespace TrackedAllocators { +// We use memory_order_relaxed updates of the following counters. Values are treated as approximate +// wherever concurrent updates are possible. // Running count of number of bytes used for this kind of allocation. Increased by allocations, // decreased by deallocations. extern Atomic<size_t> g_bytes_used[kAllocatorTagCount]; // Largest value of bytes used seen. -extern volatile size_t g_max_bytes_used[kAllocatorTagCount]; +extern Atomic<size_t> g_max_bytes_used[kAllocatorTagCount]; // Total number of bytes allocated of this kind. extern Atomic<uint64_t> g_total_bytes_used[kAllocatorTagCount]; @@ -84,15 +86,17 @@ extern Atomic<uint64_t> g_total_bytes_used[kAllocatorTagCount]; void Dump(std::ostream& os); inline void RegisterAllocation(AllocatorTag tag, size_t bytes) { - g_total_bytes_used[tag].fetch_add(bytes, std::memory_order_seq_cst); - size_t new_bytes = g_bytes_used[tag].fetch_add(bytes, std::memory_order_seq_cst) + bytes; - if (g_max_bytes_used[tag] < new_bytes) { - g_max_bytes_used[tag] = new_bytes; + g_total_bytes_used[tag].fetch_add(bytes, std::memory_order_relaxed); + size_t new_bytes = g_bytes_used[tag].fetch_add(bytes, std::memory_order_relaxed) + bytes; + size_t max_bytes = g_max_bytes_used[tag].load(std::memory_order_relaxed); + while (max_bytes < new_bytes + && !g_max_bytes_used[tag].compare_exchange_weak(max_bytes /* updated */, new_bytes, + std::memory_order_relaxed)) { } } inline void RegisterFree(AllocatorTag tag, size_t bytes) { - g_bytes_used[tag].fetch_sub(bytes, std::memory_order_seq_cst); + g_bytes_used[tag].fetch_sub(bytes, std::memory_order_relaxed); } } // namespace TrackedAllocators |