Marek Olšák | 761ff40 | 2016-08-27 19:52:31 +0200 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2010 Marek Olšák <maraeo@gmail.com> |
| 3 | * Copyright 2016 Advanced Micro Devices, Inc. |
| 4 | * |
| 5 | * Permission is hereby granted, free of charge, to any person obtaining a |
| 6 | * copy of this software and associated documentation files (the "Software"), |
| 7 | * to deal in the Software without restriction, including without limitation |
| 8 | * on the rights to use, copy, modify, merge, publish, distribute, sub |
| 9 | * license, and/or sell copies of the Software, and to permit persons to whom |
| 10 | * the Software is furnished to do so, subject to the following conditions: |
| 11 | * |
| 12 | * The above copyright notice and this permission notice (including the next |
| 13 | * paragraph) shall be included in all copies or substantial portions of the |
| 14 | * Software. |
| 15 | * |
| 16 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 17 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 18 | * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL |
| 19 | * THE AUTHOR(S) AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM, |
| 20 | * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR |
| 21 | * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE |
| 22 | * USE OR OTHER DEALINGS IN THE SOFTWARE. */ |
| 23 | |
| 24 | /** |
| 25 | * Slab allocator for equally sized memory allocations. |
| 26 | * The thread-safe path ("*_mt" functions) is usually slower than malloc/free. |
| 27 | * The single-threaded path ("*_st" functions) is faster than malloc/free. |
| 28 | */ |
| 29 | |
| 30 | #ifndef SLAB_H |
| 31 | #define SLAB_H |
| 32 | |
| 33 | #include "c11/threads.h" |
| 34 | |
| 35 | /* The page is an array of allocations in one block. */ |
| 36 | struct slab_page_header { |
| 37 | /* The header (linked-list pointers). */ |
| 38 | struct slab_page_header *prev, *next; |
| 39 | |
| 40 | /* Memory after the last member is dedicated to the page itself. |
| 41 | * The allocated size is always larger than this structure. |
| 42 | */ |
| 43 | }; |
| 44 | |
| 45 | struct slab_mempool { |
| 46 | mtx_t mutex; |
| 47 | unsigned element_size; |
| 48 | unsigned num_elements; |
| 49 | struct slab_element_header *first_free; |
| 50 | struct slab_page_header list; |
| 51 | }; |
| 52 | |
| 53 | void slab_create(struct slab_mempool *pool, |
| 54 | unsigned item_size, |
| 55 | unsigned num_items); |
| 56 | void slab_destroy(struct slab_mempool *pool); |
| 57 | void *slab_alloc_st(struct slab_mempool *pool); |
| 58 | void slab_free_st(struct slab_mempool *pool, void *ptr); |
| 59 | void *slab_alloc_mt(struct slab_mempool *pool); |
| 60 | void slab_free_mt(struct slab_mempool *pool, void *ptr); |
| 61 | |
| 62 | #endif |