| /* |
| * Copyright 2016-present Facebook, Inc. |
| * |
| * 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. |
| */ |
| |
| // https://github.com/jemalloc/jemalloc/releases |
| // Requires jemalloc 5.0.0 or above. |
| |
| #pragma once |
| |
| #include "tscore/ink_config.h" |
| #include "tscore/ink_queue.h" |
| #include <sys/mman.h> |
| #include <cstddef> |
| |
| #if TS_HAS_JEMALLOC |
| #include <jemalloc/jemalloc.h> |
| #if (JEMALLOC_VERSION_MAJOR == 0) |
| #error jemalloc has bogus version |
| #endif |
| #if (JEMALLOC_VERSION_MAJOR == 5) && defined(MADV_DONTDUMP) |
| #define JEMALLOC_NODUMP_ALLOCATOR_SUPPORTED 1 |
| #endif /* MADV_DONTDUMP */ |
| #endif /* TS_HAS_JEMALLOC */ |
| |
| namespace jearena |
| { |
| /** |
| * An allocator which uses Jemalloc to create an dedicated arena to allocate |
| * memory from. The only special property set on the allocated memory is that |
| * the memory is not dump-able. |
| * |
| * This is done by setting MADV_DONTDUMP using the `madvise` system call. A |
| * custom hook installed which is called when allocating a new chunk / extent of |
| * memory. All it does is call the original jemalloc hook to allocate the |
| * memory and then set the advise on it before returning the pointer to the |
| * allocated memory. Jemalloc does not use allocated chunks / extents across |
| * different arenas, without `munmap`-ing them first, and the advises are not |
| * sticky i.e. they are unset if `munmap` is done. Also this arena can't be used |
| * by any other part of the code by just calling `malloc`. |
| * |
| * If target system doesn't support MADV_DONTDUMP or jemalloc doesn't support |
| * custom arena hook, JemallocNodumpAllocator would fall back to using malloc / |
| * free. Such behavior can be identified by using |
| * !defined(JEMALLOC_NODUMP_ALLOCATOR_SUPPORTED). |
| * |
| * Similarly, if binary isn't linked with jemalloc, the logic would fall back to |
| * malloc / free. |
| */ |
| class JemallocNodumpAllocator |
| { |
| public: |
| explicit JemallocNodumpAllocator(); |
| |
| void *allocate(InkFreeList *f); |
| void deallocate(InkFreeList *f, void *ptr); |
| |
| private: |
| #if JEMALLOC_NODUMP_ALLOCATOR_SUPPORTED |
| static extent_hooks_t extent_hooks_; |
| static extent_alloc_t *original_alloc_; |
| static void *alloc(extent_hooks_t *extent, void *new_addr, size_t size, size_t alignment, bool *zero, bool *commit, |
| unsigned arena_ind); |
| |
| unsigned arena_index_{0}; |
| int flags_{0}; |
| #endif /* JEMALLOC_NODUMP_ALLOCATOR_SUPPORTED */ |
| |
| bool extend_and_setup_arena(); |
| }; |
| |
| /** |
| * JemallocNodumpAllocator singleton. |
| */ |
| JemallocNodumpAllocator &globalJemallocNodumpAllocator(); |
| |
| } /* namespace jearena */ |