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Diffstat (limited to 'src/util/slab.h')
-rw-r--r-- | src/util/slab.h | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/src/util/slab.h b/src/util/slab.h new file mode 100644 index 00000000000..9d13f6ad69d --- /dev/null +++ b/src/util/slab.h @@ -0,0 +1,62 @@ +/* + * Copyright 2010 Marek Olšák <[email protected]> + * Copyright 2016 Advanced Micro Devices, Inc. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * on the rights to use, copy, modify, merge, publish, distribute, sub + * license, and/or sell copies of the Software, and to permit persons to whom + * the Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL + * THE AUTHOR(S) AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM, + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE + * USE OR OTHER DEALINGS IN THE SOFTWARE. */ + +/** + * Slab allocator for equally sized memory allocations. + * The thread-safe path ("*_mt" functions) is usually slower than malloc/free. + * The single-threaded path ("*_st" functions) is faster than malloc/free. + */ + +#ifndef SLAB_H +#define SLAB_H + +#include "c11/threads.h" + +/* The page is an array of allocations in one block. */ +struct slab_page_header { + /* The header (linked-list pointers). */ + struct slab_page_header *prev, *next; + + /* Memory after the last member is dedicated to the page itself. + * The allocated size is always larger than this structure. + */ +}; + +struct slab_mempool { + mtx_t mutex; + unsigned element_size; + unsigned num_elements; + struct slab_element_header *first_free; + struct slab_page_header list; +}; + +void slab_create(struct slab_mempool *pool, + unsigned item_size, + unsigned num_items); +void slab_destroy(struct slab_mempool *pool); +void *slab_alloc_st(struct slab_mempool *pool); +void slab_free_st(struct slab_mempool *pool, void *ptr); +void *slab_alloc_mt(struct slab_mempool *pool); +void slab_free_mt(struct slab_mempool *pool, void *ptr); + +#endif |