1 /* 2 * Copyright (c) 2016-2020, Yann Collet, Facebook, Inc. 3 * All rights reserved. 4 * 5 * This source code is licensed under both the BSD-style license (found in the 6 * LICENSE file in the root directory of this source tree) and the GPLv2 (found 7 * in the COPYING file in the root directory of this source tree). 8 * You may select, at your option, one of the above-listed licenses. 9 */ 10 11 #ifndef POOL_H 12 #define POOL_H 13 14 #if defined (__cplusplus) 15 extern "C" { 16 #endif 17 18 19 #include <stddef.h> /* size_t */ 20 #define ZSTD_STATIC_LINKING_ONLY /* ZSTD_customMem */ 21 #include "../zstd.h" 22 23 typedef struct POOL_ctx_s POOL_ctx; 24 25 /*! POOL_create() : 26 * Create a thread pool with at most `numThreads` threads. 27 * `numThreads` must be at least 1. 28 * The maximum number of queued jobs before blocking is `queueSize`. 29 * @return : POOL_ctx pointer on success, else NULL. 30 */ 31 POOL_ctx* POOL_create(size_t numThreads, size_t queueSize); 32 33 POOL_ctx* POOL_create_advanced(size_t numThreads, size_t queueSize, 34 ZSTD_customMem customMem); 35 36 /*! POOL_free() : 37 * Free a thread pool returned by POOL_create(). 38 */ 39 void POOL_free(POOL_ctx* ctx); 40 41 /*! POOL_resize() : 42 * Expands or shrinks pool's number of threads. 43 * This is more efficient than releasing + creating a new context, 44 * since it tries to preserve and re-use existing threads. 45 * `numThreads` must be at least 1. 46 * @return : 0 when resize was successful, 47 * !0 (typically 1) if there is an error. 48 * note : only numThreads can be resized, queueSize remains unchanged. 49 */ 50 int POOL_resize(POOL_ctx* ctx, size_t numThreads); 51 52 /*! POOL_sizeof() : 53 * @return threadpool memory usage 54 * note : compatible with NULL (returns 0 in this case) 55 */ 56 size_t POOL_sizeof(POOL_ctx* ctx); 57 58 /*! POOL_function : 59 * The function type that can be added to a thread pool. 60 */ 61 typedef void (*POOL_function)(void*); 62 63 /*! POOL_add() : 64 * Add the job `function(opaque)` to the thread pool. `ctx` must be valid. 65 * Possibly blocks until there is room in the queue. 66 * Note : The function may be executed asynchronously, 67 * therefore, `opaque` must live until function has been completed. 68 */ 69 void POOL_add(POOL_ctx* ctx, POOL_function function, void* opaque); 70 71 72 /*! POOL_tryAdd() : 73 * Add the job `function(opaque)` to thread pool _if_ a worker is available. 74 * Returns immediately even if not (does not block). 75 * @return : 1 if successful, 0 if not. 76 */ 77 int POOL_tryAdd(POOL_ctx* ctx, POOL_function function, void* opaque); 78 79 80 #if defined (__cplusplus) 81 } 82 #endif 83 84 #endif 85