From 153529400c2267c796bfc720ec7e8bfcddd98f43 Mon Sep 17 00:00:00 2001 From: Anton Khirnov Date: Tue, 4 Dec 2018 12:10:35 +0100 Subject: Initial commit. --- LICENCE | 674 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Makefile | 25 +++ libthreadpool.v | 4 + threadpool.c | 215 ++++++++++++++++++ threadpool.h | 66 ++++++ worker.c | 137 ++++++++++++ worker.h | 71 ++++++ 7 files changed, 1192 insertions(+) create mode 100644 LICENCE create mode 100644 Makefile create mode 100644 libthreadpool.v create mode 100644 threadpool.c create mode 100644 threadpool.h create mode 100644 worker.c create mode 100644 worker.h diff --git a/LICENCE b/LICENCE new file mode 100644 index 0000000..94a9ed0 --- /dev/null +++ b/LICENCE @@ -0,0 +1,674 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. 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If not, see . + +Also add information on how to contact you by electronic and paper mail. + + If the program does terminal interaction, make it output a short +notice like this when it starts in an interactive mode: + + Copyright (C) + This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, your program's commands +might be different; for a GUI interface, you would use an "about box". + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU GPL, see +. + + The GNU General Public License does not permit incorporating your program +into proprietary programs. If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. diff --git a/Makefile b/Makefile new file mode 100644 index 0000000..d2c4b7d --- /dev/null +++ b/Makefile @@ -0,0 +1,25 @@ +CFLAGS = -std=c11 -D_XOPEN_SOURCE=700 -fPIC -g -O3 -Wall -fsanitize=thread +LIBS=-lm +LDFLAGS = -Wl,--version-script=libthreadpool.v -shared -pthread $(LIBS) -fsanitize=thread +CC = cc + +TARGET = libthreadpool.so + +OBJECTS = \ + threadpool.o \ + worker.o \ + +all: $(TARGET) + +$(TARGET): $(OBJECTS) + $(CC) ${LDFLAGS} -o $@ $(OBJECTS) + +%.o: %.c + $(CC) $(CFLAGS) -MMD -MF $(@:.o=.d) -MT $@ -c -o $@ $< + +clean: + -rm -f $(OBJECTS) $(TARGET) + +-include $(OBJECTS:.o=.d) + +.PHONY: clean diff --git a/libthreadpool.v b/libthreadpool.v new file mode 100644 index 0000000..e8fe7b5 --- /dev/null +++ b/libthreadpool.v @@ -0,0 +1,4 @@ +LIBTHREADPOOL_1 { + global: tp_*; + local: *; +}; diff --git a/threadpool.c b/threadpool.c new file mode 100644 index 0000000..50d8cb7 --- /dev/null +++ b/threadpool.c @@ -0,0 +1,215 @@ +/* + * Copyright 2018 Anton Khirnov + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#include +#include +#include +#include +#include +#include + +#include "threadpool.h" +#include "worker.h" + +#include + +#define MIN(x, y) ((x) < (y) ? (x) : (y)) + +struct TPContext { + struct { + Worker *w; + WorkBatch wb; + int have_work; + + pthread_mutex_t work_lock; + pthread_cond_t work_cond; + + atomic_int work_completed; + atomic_int queue_empty; + + unsigned int rand_seed; + } *workers; + unsigned int nb_workers; + + atomic_int finish; + + pthread_mutex_t execute_lock; + + pthread_mutex_t progress_lock; + pthread_cond_t progress_cond; + atomic_int nb_workers_finished; + + atomic_int nb_workers_queue_empty; +}; + +void tp_free(TPContext **pctx) +{ + TPContext *ctx = *pctx; + + if (!ctx) + return; + + atomic_store(&ctx->finish, 1); + + for (unsigned int i = 0; i < ctx->nb_workers; i++) { + pthread_mutex_lock(&ctx->workers[i].work_lock); + pthread_cond_signal(&ctx->workers[i].work_cond); + pthread_mutex_unlock(&ctx->workers[i].work_lock); + + tpi_worker_destroy(&ctx->workers[i].w); + pthread_mutex_destroy(&ctx->workers[i].work_lock); + pthread_cond_destroy(&ctx->workers[i].work_cond); + } + free(ctx->workers); + ctx->nb_workers = 0; + + pthread_mutex_destroy(&ctx->execute_lock); + + free(ctx); + *pctx = NULL; +} + +int tp_init(TPContext **pctx, unsigned int nb_threads) +{ + TPContext *ctx = NULL; + int ret; + + if (!nb_threads) { + ret = -EINVAL; + goto fail; + } + + ctx = calloc(1, sizeof(*ctx)); + if (!ctx) { + ret = -ENOMEM; + goto fail; + } + + pthread_mutex_init(&ctx->execute_lock, NULL); + atomic_store(&ctx->finish, 0); + + ctx->workers = calloc(nb_threads, sizeof(*ctx->workers)); + if (!ctx->workers) { + ret = -ENOMEM; + goto fail; + } + + for (unsigned int i = 0; i < nb_threads; i++) { + struct timeval tv; + + pthread_mutex_init(&ctx->workers[i].work_lock, NULL); + pthread_cond_init(&ctx->workers[i].work_cond, NULL); + + gettimeofday(&tv, NULL); + ctx->workers[i].rand_seed = tv.tv_usec; + + ret = tpi_worker_spawn(&ctx->workers[i].w, i, ctx); + if (ret < 0) + goto fail; + ctx->nb_workers++; + } + + *pctx = ctx; + return 0; + +fail: + tp_free(&ctx); + *pctx = NULL; + return ret; +} + +int tpi_worksource_wait_jobs(TPContext *ctx, unsigned int worker_idx, + WorkBatch *wb) +{ + pthread_mutex_lock(&ctx->progress_lock); + atomic_store(&ctx->workers[worker_idx].work_completed, 1); + atomic_fetch_add(&ctx->nb_workers_finished, 1); + pthread_cond_signal(&ctx->progress_cond); + pthread_mutex_unlock(&ctx->progress_lock); + + pthread_mutex_lock(&ctx->workers[worker_idx].work_lock); + + while (!atomic_load(&ctx->finish) && !ctx->workers[worker_idx].have_work) + pthread_cond_wait(&ctx->workers[worker_idx].work_cond, &ctx->workers[worker_idx].work_lock); + + memcpy(wb, &ctx->workers[worker_idx].wb, sizeof(*wb)); + wb->finish = atomic_load(&ctx->finish); + ctx->workers[worker_idx].have_work = 0; + + pthread_mutex_unlock(&ctx->workers[worker_idx].work_lock); + + return 0; +} + +int tpi_worksource_steal_job(TPContext *ctx, unsigned int worker_idx) +{ + int ret = -1; + + atomic_store(&ctx->workers[worker_idx].queue_empty, 1); + atomic_fetch_add(&ctx->nb_workers_queue_empty, 1); + + while (atomic_load(&ctx->nb_workers_queue_empty) < ctx->nb_workers) { + unsigned int w_victim_idx = rand_r(&ctx->workers[worker_idx].rand_seed) % ctx->nb_workers; + + if (w_victim_idx == worker_idx || atomic_load(&ctx->workers[w_victim_idx].queue_empty)) + continue; + + ret = tpi_worker_steal_job(ctx->workers[w_victim_idx].w); + if (ret >= 0) + break; + } + + return ret; +} + +int tp_execute(TPContext *ctx, unsigned int nb_jobs, + TPExecuteCallback func, void *func_arg) +{ + unsigned int max_batch_size = (nb_jobs + ctx->nb_workers - 1) / ctx->nb_workers; + + pthread_mutex_lock(&ctx->execute_lock); + + atomic_store(&ctx->nb_workers_finished, 0); + atomic_store(&ctx->nb_workers_queue_empty, 0); + + for (unsigned int i = 0; i < ctx->nb_workers; i++) { + WorkBatch *wb = &ctx->workers[i].wb; + + pthread_mutex_lock(&ctx->workers[i].work_lock); + + wb->job_func = func; + wb->func_arg = func_arg; + wb->job_idx_start = i * max_batch_size; + wb->job_idx_end = MIN((i + 1) * max_batch_size, nb_jobs); + ctx->workers[i].have_work = 1; + atomic_store(&ctx->workers[i].work_completed, 0); + atomic_store(&ctx->workers[i].queue_empty, 0); + + pthread_cond_signal(&ctx->workers[i].work_cond); + + pthread_mutex_unlock(&ctx->workers[i].work_lock); + } + + pthread_mutex_lock(&ctx->progress_lock); + while (atomic_load(&ctx->nb_workers_finished) < ctx->nb_workers) + pthread_cond_wait(&ctx->progress_cond, &ctx->progress_lock); + pthread_mutex_unlock(&ctx->progress_lock); + + pthread_mutex_unlock(&ctx->execute_lock); + + return 0; +} diff --git a/threadpool.h b/threadpool.h new file mode 100644 index 0000000..17bf3f2 --- /dev/null +++ b/threadpool.h @@ -0,0 +1,66 @@ +/* + * Copyright 2016-2018 Anton Khirnov + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#ifndef TP_THREADPOOL_H +#define TP_THREADPOOL_H + +/** + * The thread pool object, allocated by tp_init() and destroyed by tp_free(). + */ +typedef struct TPContext TPContext; + +/** + * The callback passed to tp_execute(). + * + * @param arg the user pointer supplied to tp_execute + * @param job_idx the job index, between 0 and nb_jobs + * @param thread_idx the index of the thread executing this job, between 0 and + * nb_threads + * + * @return the callback should return 0 on success and a negative number on + * failure + */ +typedef int (*TPExecuteCallback)(void *arg, unsigned int job_idx, unsigned int thread_idx); + +/** + * Create the thread pool object. + * + * @param ctx the newly created thread pool will be written here + * @param nb_threads the number of threads to execute in parallel + * @return 0 on success, a negative error code on failure + */ +int tp_init(TPContext **ctx, unsigned int nb_threads); +/** + * Free the thread pool object and write NULL into the supplied pointer. + */ +void tp_free(TPContext **ctx); + +/** + * Execute a function multiple times in parallel. + * + * @param ctx the thread pool object + * @param nb_jobs number of times to call func + * @param func the callback to call + * @param func_arg arbitrary user data to pass to func + * + * @return 0 if all the calls to func returned successfully, a negative error + * code otherwise + */ +int tp_execute(TPContext *ctx, unsigned int nb_jobs, + TPExecuteCallback func, void *func_arg); + +#endif /* TP_THREADPOOL_H */ diff --git a/worker.c b/worker.c new file mode 100644 index 0000000..306bc10 --- /dev/null +++ b/worker.c @@ -0,0 +1,137 @@ +/* + * Copyright 2018 Anton Khirnov + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#include +#include +#include +#include + +#include "worker.h" + +struct Worker { + WorkSource *ws; + unsigned int worker_idx; + pthread_t thread_id; + + pthread_mutex_t wb_lock; + atomic_int job_idx_start; + atomic_int job_idx_end; +}; + +int tpi_worker_steal_job(Worker *w) +{ + int ret = -1; + + pthread_mutex_lock(&w->wb_lock); + + if (w->job_idx_start < w->job_idx_end) + ret = --w->job_idx_end; + + pthread_mutex_unlock(&w->wb_lock); + + return ret; +} + +static int worker_get_next_job(Worker *w) +{ + int ret = -1; + + pthread_mutex_lock(&w->wb_lock); + + if (w->job_idx_start < w->job_idx_end) + ret = w->job_idx_start++; + + pthread_mutex_unlock(&w->wb_lock); + + if (ret < 0) + ret = tpi_worksource_steal_job(w->ws, w->worker_idx); + + return ret; +} + +static void *worker_thread(void *arg) +{ + Worker *w = arg; + int ret; + + while (1) { + WorkBatch wb; + + ret = tpi_worksource_wait_jobs(w->ws, w->worker_idx, &wb); + if (ret < 0 || wb.finish) + break; + + pthread_mutex_lock(&w->wb_lock); + atomic_store(&w->job_idx_start, wb.job_idx_start); + atomic_store(&w->job_idx_end, wb.job_idx_end); + pthread_mutex_unlock(&w->wb_lock); + + while ((ret = worker_get_next_job(w)) >= 0) + wb.job_func(wb.func_arg, ret, w->worker_idx); + } + + return NULL; +} + +int tpi_worker_spawn(Worker **pw, unsigned int worker_idx, WorkSource *ws) +{ + Worker *w; + int ret; + + w = calloc(1, sizeof(*w)); + if (!w) + return -ENOMEM; + + ret = pthread_mutex_init(&w->wb_lock, NULL); + if (ret != 0) { + ret = -ret; + goto fail_free; + } + + w->worker_idx = worker_idx; + w->ws = ws; + + atomic_store(&w->job_idx_start, -1); + atomic_store(&w->job_idx_end, -1); + + ret = pthread_create(&w->thread_id, NULL, worker_thread, w); + if (ret != 0) { + ret = -ret; + goto fail_free; + } + + *pw = w; + return 0; +fail_free: + free(w); + return ret; +} + +void tpi_worker_destroy(Worker **pw) +{ + Worker *w = *pw; + + if (!w) + return; + + pthread_join(w->thread_id, NULL); + + pthread_mutex_destroy(&w->wb_lock); + + free(w); + *pw = NULL; +} diff --git a/worker.h b/worker.h new file mode 100644 index 0000000..1fa87d8 --- /dev/null +++ b/worker.h @@ -0,0 +1,71 @@ +/* + * Copyright 2018 Anton Khirnov + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +/** + * This is the public API for interaction between the individual worker threads + * and the pool. + */ + +#ifndef TP_WORKER_H +#define TP_WORKER_H + +typedef struct TPContext WorkSource; + +typedef struct WorkBatch { + int (*job_func)(void *arg, unsigned int job_idx, unsigned int thread_idx); + void *func_arg; + + unsigned int job_idx_start; + unsigned int job_idx_end; + int finish; +} WorkBatch; + +/** + * Called by the worker with index worker_idx to wait for a new batch of jobs. + * + * @return 0 if wb has been successfully filled, a negative error otherwise + */ +int tpi_worksource_wait_jobs(WorkSource *ws, unsigned int worker_idx, + WorkBatch *wb); + +/** + * Steal a job from another worker. + * + * @return a non-negative job index if a job was successfully stolen + * -1 if there are no more jobs available + */ +int tpi_worksource_steal_job(WorkSource *ws, unsigned int worker_idx); + +typedef struct Worker Worker; + +/** + * Launch a new worker with the given unique index worker_idx. + * + * @return 0 if the worker has been launched, a negative error code otherwise + */ +int tpi_worker_spawn(Worker **w, unsigned int worker_idx, WorkSource *ws); +void tpi_worker_destroy(Worker **w); + +/** + * Called by the work source to steal a job. + * + * @return a non-negative job index if a job was successfully stolen + * -1 if there are no more jobs available. + */ +int tpi_worker_steal_job(Worker *w); + +#endif // TP_WORKER_H -- cgit v1.2.3