From c2e754829628d1e9b7a16b3389cfdace76950fdf Mon Sep 17 00:00:00 2001 From: misterg Date: Tue, 19 Sep 2017 16:54:40 -0400 Subject: Initial Commit --- absl/base/internal/malloc_extension.cc | 197 +++++++++++++++++++++++++++++++++ 1 file changed, 197 insertions(+) create mode 100644 absl/base/internal/malloc_extension.cc (limited to 'absl/base/internal/malloc_extension.cc') diff --git a/absl/base/internal/malloc_extension.cc b/absl/base/internal/malloc_extension.cc new file mode 100644 index 00000000..daf4bc32 --- /dev/null +++ b/absl/base/internal/malloc_extension.cc @@ -0,0 +1,197 @@ +// Copyright 2017 The Abseil Authors. +// +// 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. + +#include "absl/base/internal/malloc_extension.h" + +#include +#include +#include +#include +#include +#include + +#include "absl/base/dynamic_annotations.h" +#include "absl/base/internal/malloc_extension_c.h" +#include "absl/base/port.h" + +namespace absl { +namespace base_internal { + +// SysAllocator implementation +SysAllocator::~SysAllocator() {} +void SysAllocator::GetStats(char* buffer, int) { buffer[0] = 0; } + +// Default implementation -- does nothing +MallocExtension::~MallocExtension() { } +bool MallocExtension::VerifyAllMemory() { return true; } +bool MallocExtension::VerifyNewMemory(const void*) { return true; } +bool MallocExtension::VerifyArrayNewMemory(const void*) { return true; } +bool MallocExtension::VerifyMallocMemory(const void*) { return true; } + +bool MallocExtension::GetNumericProperty(const char*, size_t*) { + return false; +} + +bool MallocExtension::SetNumericProperty(const char*, size_t) { + return false; +} + +void MallocExtension::GetStats(char* buffer, int length) { + assert(length > 0); + static_cast(length); + buffer[0] = '\0'; +} + +bool MallocExtension::MallocMemoryStats(int* blocks, size_t* total, + int histogram[kMallocHistogramSize]) { + *blocks = 0; + *total = 0; + memset(histogram, 0, sizeof(*histogram) * kMallocHistogramSize); + return true; +} + +void MallocExtension::MarkThreadIdle() { + // Default implementation does nothing +} + +void MallocExtension::MarkThreadBusy() { + // Default implementation does nothing +} + +SysAllocator* MallocExtension::GetSystemAllocator() { + return nullptr; +} + +void MallocExtension::SetSystemAllocator(SysAllocator*) { + // Default implementation does nothing +} + +void MallocExtension::ReleaseToSystem(size_t) { + // Default implementation does nothing +} + +void MallocExtension::ReleaseFreeMemory() { + ReleaseToSystem(static_cast(-1)); // SIZE_T_MAX +} + +void MallocExtension::SetMemoryReleaseRate(double) { + // Default implementation does nothing +} + +double MallocExtension::GetMemoryReleaseRate() { + return -1.0; +} + +size_t MallocExtension::GetEstimatedAllocatedSize(size_t size) { + return size; +} + +size_t MallocExtension::GetAllocatedSize(const void* p) { + assert(GetOwnership(p) != kNotOwned); + static_cast(p); + return 0; +} + +MallocExtension::Ownership MallocExtension::GetOwnership(const void*) { + return kUnknownOwnership; +} + +void MallocExtension::GetProperties(MallocExtension::StatLevel, + std::map* result) { + result->clear(); +} + +size_t MallocExtension::ReleaseCPUMemory(int) { + return 0; +} + +// The current malloc extension object. + +std::atomic MallocExtension::current_instance_; + +MallocExtension* MallocExtension::InitModule() { + MallocExtension* ext = new MallocExtension; + current_instance_.store(ext, std::memory_order_release); + return ext; +} + +void MallocExtension::Register(MallocExtension* implementation) { + InitModuleOnce(); + // When running under valgrind, our custom malloc is replaced with + // valgrind's one and malloc extensions will not work. (Note: + // callers should be responsible for checking that they are the + // malloc that is really being run, before calling Register. This + // is just here as an extra sanity check.) + // Under compiler-based ThreadSanitizer RunningOnValgrind() returns true, + // but we still want to use malloc extensions. +#ifndef THREAD_SANITIZER + if (RunningOnValgrind()) { + return; + } +#endif // #ifndef THREAD_SANITIZER + current_instance_.store(implementation, std::memory_order_release); +} +void MallocExtension::GetHeapSample(MallocExtensionWriter*) {} + +void MallocExtension::GetHeapGrowthStacks(MallocExtensionWriter*) {} + +void MallocExtension::GetFragmentationProfile(MallocExtensionWriter*) {} + +} // namespace base_internal +} // namespace absl + +// These are C shims that work on the current instance. + +#define C_SHIM(fn, retval, paramlist, arglist) \ + extern "C" retval MallocExtension_##fn paramlist { \ + return absl::base_internal::MallocExtension::instance()->fn arglist; \ + } + +C_SHIM(VerifyAllMemory, int, (void), ()); +C_SHIM(VerifyNewMemory, int, (const void* p), (p)); +C_SHIM(VerifyArrayNewMemory, int, (const void* p), (p)); +C_SHIM(VerifyMallocMemory, int, (const void* p), (p)); +C_SHIM( + MallocMemoryStats, int, + (int* blocks, size_t* total, + int histogram[absl::base_internal::MallocExtension::kMallocHistogramSize]), + (blocks, total, histogram)); + +C_SHIM(GetStats, void, + (char* buffer, int buffer_length), (buffer, buffer_length)); +C_SHIM(GetNumericProperty, int, + (const char* property, size_t* value), (property, value)); +C_SHIM(SetNumericProperty, int, + (const char* property, size_t value), (property, value)); + +C_SHIM(MarkThreadIdle, void, (void), ()); +C_SHIM(MarkThreadBusy, void, (void), ()); +C_SHIM(ReleaseFreeMemory, void, (void), ()); +C_SHIM(ReleaseToSystem, void, (size_t num_bytes), (num_bytes)); +C_SHIM(GetEstimatedAllocatedSize, size_t, (size_t size), (size)); +C_SHIM(GetAllocatedSize, size_t, (const void* p), (p)); + +// Can't use the shim here because of the need to translate the enums. +extern "C" +MallocExtension_Ownership MallocExtension_GetOwnership(const void* p) { + return static_cast( + absl::base_internal::MallocExtension::instance()->GetOwnership(p)); +} + +// Default implementation just returns size. The expectation is that +// the linked-in malloc implementation might provide an override of +// this weak function with a better implementation. +ABSL_ATTRIBUTE_WEAK ABSL_ATTRIBUTE_NOINLINE size_t nallocx(size_t size, int) { + return size; +} -- cgit v1.2.3