1 // Copyright (c) 2013 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef BASE_PROCESS_MEMORY_H_ 6 #define BASE_PROCESS_MEMORY_H_ 7 8 #include "base/base_export.h" 9 #include "base/basictypes.h" 10 #include "base/process/process_handle.h" 11 #include "build/build_config.h" 12 13 #if defined(OS_WIN) 14 #include <windows.h> 15 #endif 16 17 #ifdef PVALLOC_AVAILABLE 18 // Build config explicitly tells us whether or not pvalloc is available. 19 #elif defined(LIBC_GLIBC) && !defined(USE_TCMALLOC) 20 #define PVALLOC_AVAILABLE 1 21 #else 22 #define PVALLOC_AVAILABLE 0 23 #endif 24 25 namespace base { 26 27 // Enables low fragmentation heap (LFH) for every heaps of this process. This 28 // won't have any effect on heaps created after this function call. It will not 29 // modify data allocated in the heaps before calling this function. So it is 30 // better to call this function early in initialization and again before 31 // entering the main loop. 32 // Note: Returns true on Windows 2000 without doing anything. 33 BASE_EXPORT bool EnableLowFragmentationHeap(); 34 35 // Enables 'terminate on heap corruption' flag. Helps protect against heap 36 // overflow. Has no effect if the OS doesn't provide the necessary facility. 37 BASE_EXPORT void EnableTerminationOnHeapCorruption(); 38 39 // Turns on process termination if memory runs out. 40 BASE_EXPORT void EnableTerminationOnOutOfMemory(); 41 42 #if defined(OS_WIN) 43 // Returns the module handle to which an address belongs. The reference count 44 // of the module is not incremented. 45 BASE_EXPORT HMODULE GetModuleFromAddress(void* address); 46 #endif 47 48 #if defined(OS_LINUX) || defined(OS_ANDROID) 49 BASE_EXPORT extern size_t g_oom_size; 50 51 // The maximum allowed value for the OOM score. 52 const int kMaxOomScore = 1000; 53 54 // This adjusts /proc/<pid>/oom_score_adj so the Linux OOM killer will 55 // prefer to kill certain process types over others. The range for the 56 // adjustment is [-1000, 1000], with [0, 1000] being user accessible. 57 // If the Linux system doesn't support the newer oom_score_adj range 58 // of [0, 1000], then we revert to using the older oom_adj, and 59 // translate the given value into [0, 15]. Some aliasing of values 60 // may occur in that case, of course. 61 BASE_EXPORT bool AdjustOOMScore(ProcessId process, int score); 62 #endif 63 64 // Special allocator functions for callers that want to check for OOM. 65 // These will not abort if the allocation fails even if 66 // EnableTerminationOnOutOfMemory has been called. 67 // This can be useful for huge and/or unpredictable size memory allocations. 68 // Please only use this if you really handle the case when the allocation 69 // fails. Doing otherwise would risk security. 70 // These functions may still crash on OOM when running under memory tools, 71 // specifically ASan and other sanitizers. 72 // Return value tells whether the allocation succeeded. If it fails |result| is 73 // set to NULL, otherwise it holds the memory address. 74 BASE_EXPORT WARN_UNUSED_RESULT bool UncheckedMalloc(size_t size, 75 void** result); 76 BASE_EXPORT WARN_UNUSED_RESULT bool UncheckedCalloc(size_t num_items, 77 size_t size, 78 void** result); 79 80 } // namespace base 81 82 #endif // BASE_PROCESS_MEMORY_H_ 83