2 * Unix SMB/CIFS implementation.
3 * threadpool implementation based on pthreads
4 * Copyright (C) Volker Lendecke 2009,2011
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
20 #ifndef __PTHREADPOOL_H__
21 #define __PTHREADPOOL_H__
26 * @defgroup pthreadpool The pthreadpool API
28 * This API provides a way to run threadsafe functions in a helper
29 * thread. It is initially intended to run getaddrinfo asynchronously.
34 * @brief Create a pthreadpool
36 * A struct pthreadpool is the basis for for running threads in the
39 * @param[in] max_threads Maximum parallelism in this pool
40 * @param[out] presult Pointer to the threadpool returned
41 * @return success: 0, failure: errno
43 * max_threads=0 means unlimited parallelism. The caller has to take
44 * care to not overload the system.
46 int pthreadpool_init(unsigned max_threads, struct pthreadpool **presult,
47 int (*signal_fn)(int jobid,
48 void (*job_fn)(void *private_data),
49 void *job_fn_private_data,
51 void *signal_fn_private_data);
54 * @brief Get the max threads value of pthreadpool
56 * @note This can be 0 for strict sync processing.
58 * @param[in] pool The pool
59 * @return number of possible threads
61 size_t pthreadpool_max_threads(struct pthreadpool *pool);
64 * @brief The number of queued jobs of pthreadpool
66 * This is the number of jobs added by pthreadpool_add_job(),
67 * which are not yet processed by a thread.
69 * @param[in] pool The pool
70 * @return The number of jobs
72 size_t pthreadpool_queued_jobs(struct pthreadpool *pool);
75 * @brief Destroy a pthreadpool
77 * Destroy a pthreadpool. If jobs are submitted, but not yet active in
78 * a thread, they won't get executed. If a job has already been
79 * submitted to a thread, the job function will continue running, and
80 * the signal function might still be called. The caller of
81 * pthreadpool_init must make sure the required resources are still
82 * around when the pool is destroyed with pending jobs. The last
83 * thread to exit will finally free() the pool memory.
85 * @param[in] pool The pool to destroy
86 * @return success: 0, failure: errno
88 int pthreadpool_destroy(struct pthreadpool *pool);
91 * @brief Add a job to a pthreadpool
93 * This adds a job to a pthreadpool. The job can be identified by
94 * job_id. This integer will be passed to signal_fn() when the
97 * @param[in] pool The pool to run the job on
98 * @param[in] job_id A custom identifier
99 * @param[in] fn The function to run asynchronously
100 * @param[in] private_data Pointer passed to fn
101 * @return success: 0, failure: errno
103 int pthreadpool_add_job(struct pthreadpool *pool, int job_id,
104 void (*fn)(void *private_data), void *private_data);
107 * @brief Try to cancel a job in a pthreadpool
109 * This tries to cancel a job in a pthreadpool. The same
110 * arguments, which were given to pthreadpool_add_job()
111 * needs to be passed.
113 * The combination of id, fn, private_data might not be unique.
114 * So the function tries to cancel as much matching jobs as possible.
115 * Note once a job is scheduled in a thread it's to late to
118 * Canceled jobs that weren't started yet won't be reported via a
121 * @param[in] pool The pool to run the job on
122 * @param[in] job_id A custom identifier
123 * @param[in] fn The function to run asynchronously
124 * @param[in] private_data Pointer passed to fn
125 * @return The number of canceled jobs
127 * @see pthreadpool_add_job()
129 size_t pthreadpool_cancel_job(struct pthreadpool *pool, int job_id,
130 void (*fn)(void *private_data), void *private_data);