| // -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- |
| // Copyright (c) 2008, Google Inc. |
| // All rights reserved. |
| // |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // * Redistributions in binary form must reproduce the above |
| // copyright notice, this list of conditions and the following disclaimer |
| // in the documentation and/or other materials provided with the |
| // distribution. |
| // * Neither the name of Google Inc. nor the names of its |
| // contributors may be used to endorse or promote products derived from |
| // this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| // --- |
| // Author: Ken Ashcraft <opensource@google.com> |
| // |
| // Static variables shared by multiple classes. |
| |
| #ifndef TCMALLOC_STATIC_VARS_H_ |
| #define TCMALLOC_STATIC_VARS_H_ |
| |
| #include "config.h" |
| |
| #include <atomic> |
| #include <cstddef> |
| |
| #include "base/basictypes.h" |
| #include "base/spinlock.h" |
| #include "base/static_storage.h" |
| #include "central_freelist.h" |
| #include "common.h" |
| #include "page_heap.h" |
| #include "page_heap_allocator.h" |
| #include "span.h" |
| #include "stack_trace_table.h" |
| |
| namespace tcmalloc { |
| |
| class Static { |
| public: |
| // Linker initialized, so this lock can be accessed at any time. |
| static SpinLock* pageheap_lock() { return pageheap()->pageheap_lock(); } |
| |
| // Must be called before calling any of the accessors below. |
| static void InitStaticVars(); |
| static void InitLateMaybeRecursive(); |
| |
| // Central cache -- an array of free-lists, one per size-class. |
| // We have a separate lock per free-list to reduce contention. |
| static CentralFreeList* central_cache() { return central_cache_; } |
| |
| static SizeMap* sizemap() { return &sizemap_; } |
| |
| static unsigned num_size_classes() { return sizemap_.num_size_classes; } |
| |
| ////////////////////////////////////////////////////////////////////// |
| // In addition to the explicit initialization comment, the variables below |
| // must be protected by pageheap_lock. |
| |
| // Page-level allocator. |
| static PageHeap* pageheap() { return pageheap_.get(); } |
| |
| static PageHeapAllocator<Span>* span_allocator() { return &span_allocator_; } |
| |
| static PageHeapAllocator<StackTrace>* stacktrace_allocator() { |
| return &stacktrace_allocator_; |
| } |
| |
| static StackTrace* growth_stacks() { return growth_stacks_.load(std::memory_order_seq_cst); } |
| static void push_growth_stack(StackTrace* s) { |
| ASSERT(s->depth <= kMaxStackDepth - 1); |
| StackTrace* old_top = growth_stacks_.load(std::memory_order_relaxed); |
| do { |
| s->stack[kMaxStackDepth-1] = reinterpret_cast<void*>(old_top); |
| } while (!growth_stacks_.compare_exchange_strong( |
| old_top, s, |
| std::memory_order_seq_cst, std::memory_order_seq_cst)); |
| } |
| |
| // State kept for sampled allocations (/pprof/heap support) |
| static Span* sampled_objects() { return &sampled_objects_; } |
| |
| // Check if InitStaticVars() has been run. |
| static bool IsInited() { return inited_; } |
| |
| private: |
| ATTRIBUTE_HIDDEN static bool inited_; |
| |
| // These static variables require explicit initialization. We cannot |
| // count on their constructors to do any initialization because other |
| // static variables may try to allocate memory before these variables |
| // can run their constructors. |
| |
| ATTRIBUTE_HIDDEN static SizeMap sizemap_; |
| ATTRIBUTE_HIDDEN static CentralFreeList central_cache_[kClassSizesMax]; |
| ATTRIBUTE_HIDDEN static PageHeapAllocator<Span> span_allocator_; |
| ATTRIBUTE_HIDDEN static PageHeapAllocator<StackTrace> stacktrace_allocator_; |
| ATTRIBUTE_HIDDEN static Span sampled_objects_; |
| |
| // Linked list of stack traces recorded every time we allocated memory |
| // from the system. Useful for finding allocation sites that cause |
| // increase in the footprint of the system. The linked list pointer |
| // is stored in trace->stack[kMaxStackDepth-1]. |
| ATTRIBUTE_HIDDEN static std::atomic<StackTrace*> growth_stacks_; |
| |
| ATTRIBUTE_HIDDEN static StaticStorage<PageHeap> pageheap_; |
| }; |
| |
| } // namespace tcmalloc |
| |
| #endif // TCMALLOC_STATIC_VARS_H_ |