Page MenuHomeClusterLabs Projects
Files F3154840

wthread.c
No OneTemporary
Actions

wthread.c
View Options

/*
* Copyright (c) 2005 MontaVista Software, Inc.
* Copyright (c) 2006, 2009 Red Hat, Inc.
*
* All rights reserved.
*
* Author: Steven Dake (sdake@redhat.com)
*
* This software licensed under BSD license, the text of which follows:
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* - Neither the name of the MontaVista Software, Inc. nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Add work to a work group and have threads process the work
* Provide blocking for all work to complete
*/
#include <config.h>
#include <stdlib.h>
#include <pthread.h>
#include <errno.h>
#include <corosync/cs_queue.h>
#include "wthread.h"
struct thread_data {
void *thread_state;
void *data;
};
struct worker_thread_t {
struct worker_thread_group *worker_thread_group;
pthread_mutex_t new_work_mutex;
pthread_cond_t new_work_cond;
pthread_cond_t cond;
pthread_mutex_t done_work_mutex;
pthread_cond_t done_work_cond;
pthread_t thread_id;
struct cs_queue queue;
void *thread_state;
struct thread_data thread_data;
};
static void *start_worker_thread (void *thread_data_in) {
struct thread_data *thread_data = (struct thread_data *)thread_data_in;
struct worker_thread_t *worker_thread =
(struct worker_thread_t *)thread_data->data;
void *data_for_worker_fn;
for (;;) {
pthread_mutex_lock (&worker_thread->new_work_mutex);
if (cs_queue_is_empty (&worker_thread->queue) == 1) {
pthread_cond_wait (&worker_thread->new_work_cond,
&worker_thread->new_work_mutex);
}
/*
* We unlock then relock the new_work_mutex to allow the
* worker function to execute and also allow new work to be
* added to the work queue
*/
data_for_worker_fn = cs_queue_item_get (&worker_thread->queue);
pthread_mutex_unlock (&worker_thread->new_work_mutex);
worker_thread->worker_thread_group->worker_fn (worker_thread->thread_state, data_for_worker_fn);
pthread_mutex_lock (&worker_thread->new_work_mutex);
cs_queue_item_remove (&worker_thread->queue);
pthread_mutex_unlock (&worker_thread->new_work_mutex);
pthread_mutex_lock (&worker_thread->done_work_mutex);
if (cs_queue_is_empty (&worker_thread->queue) == 1) {
pthread_cond_signal (&worker_thread->done_work_cond);
}
pthread_mutex_unlock (&worker_thread->done_work_mutex);
}
return (NULL);
}
int worker_thread_group_init (
struct worker_thread_group *worker_thread_group,
int threads,
int items_max,
int item_size,
int thread_state_size,
void (*thread_state_constructor)(void *),
void (*worker_fn)(void *thread_state, void *work_item))
{
int i;
worker_thread_group->threadcount = threads;
worker_thread_group->last_scheduled = 0;
worker_thread_group->worker_fn = worker_fn;
worker_thread_group->threads = malloc (sizeof (struct worker_thread_t) *
threads);
if (worker_thread_group->threads == 0) {
return (-1);
}
for (i = 0; i < threads; i++) {
if (thread_state_size) {
worker_thread_group->threads[i].thread_state = malloc (thread_state_size);
} else {
worker_thread_group->threads[i].thread_state = NULL;
}
if (thread_state_constructor) {
thread_state_constructor (worker_thread_group->threads[i].thread_state);
}
worker_thread_group->threads[i].worker_thread_group = worker_thread_group;
pthread_mutex_init (&worker_thread_group->threads[i].new_work_mutex, NULL);
pthread_cond_init (&worker_thread_group->threads[i].new_work_cond, NULL);
pthread_mutex_init (&worker_thread_group->threads[i].done_work_mutex, NULL);
pthread_cond_init (&worker_thread_group->threads[i].done_work_cond, NULL);
cs_queue_init (&worker_thread_group->threads[i].queue, items_max,
item_size);
worker_thread_group->threads[i].thread_data.thread_state =
worker_thread_group->threads[i].thread_state;
worker_thread_group->threads[i].thread_data.data = &worker_thread_group->threads[i];
pthread_create (&worker_thread_group->threads[i].thread_id,
NULL, start_worker_thread, &worker_thread_group->threads[i].thread_data);
}
return (0);
}
int worker_thread_group_work_add (
struct worker_thread_group *worker_thread_group,
void *item)
{
int schedule;
schedule = (worker_thread_group->last_scheduled + 1) % (worker_thread_group->threadcount);
worker_thread_group->last_scheduled = schedule;
pthread_mutex_lock (&worker_thread_group->threads[schedule].new_work_mutex);
if (cs_queue_is_full (&worker_thread_group->threads[schedule].queue)) {
pthread_mutex_unlock (&worker_thread_group->threads[schedule].new_work_mutex);
return (-1);
}
cs_queue_item_add (&worker_thread_group->threads[schedule].queue, item);
pthread_cond_signal (&worker_thread_group->threads[schedule].new_work_cond);
pthread_mutex_unlock (&worker_thread_group->threads[schedule].new_work_mutex);
return (0);
}
void worker_thread_group_wait (
struct worker_thread_group *worker_thread_group)
{
int i;
for (i = 0; i < worker_thread_group->threadcount; i++) {
pthread_mutex_lock (&worker_thread_group->threads[i].done_work_mutex);
if (cs_queue_is_empty (&worker_thread_group->threads[i].queue) == 0) {
pthread_cond_wait (&worker_thread_group->threads[i].done_work_cond,
&worker_thread_group->threads[i].done_work_mutex);
}
pthread_mutex_unlock (&worker_thread_group->threads[i].done_work_mutex);
}
}
void worker_thread_group_exit (
struct worker_thread_group *worker_thread_group)
{
int i;
for (i = 0; i < worker_thread_group->threadcount; i++) {
pthread_cancel (worker_thread_group->threads[i].thread_id);
/* Wait for worker thread to exit gracefully before destroying
* mutexes and processing items in the queue etc.
*/
pthread_join (worker_thread_group->threads[i].thread_id, NULL);
pthread_mutex_destroy (&worker_thread_group->threads[i].new_work_mutex);
pthread_cond_destroy (&worker_thread_group->threads[i].new_work_cond);
pthread_mutex_destroy (&worker_thread_group->threads[i].done_work_mutex);
pthread_cond_destroy (&worker_thread_group->threads[i].done_work_cond);
}
}
void worker_thread_group_atsegv (
struct worker_thread_group *worker_thread_group)
{
void *data_for_worker_fn;
struct worker_thread_t *worker_thread;
unsigned int i;
for (i = 0; i < worker_thread_group->threadcount; i++) {
worker_thread = &worker_thread_group->threads[i];
while (cs_queue_is_empty (&worker_thread->queue) == 0) {
data_for_worker_fn = cs_queue_item_get (&worker_thread->queue);
worker_thread->worker_thread_group->worker_fn (worker_thread->thread_state, data_for_worker_fn);
cs_queue_item_remove (&worker_thread->queue);
}
}
}

File Metadata

Mime Type
text/x-c
Expires
Wed, Feb 26, 4:54 PM (6 h, 55 m)
Storage Engine
blob
Storage Format
Raw Data
Storage Handle
1367239
Default Alt Text
wthread.c (7 KB)

Event Timeline