*
*/
/*
- Copyright (C) 2000, 2001, 2002 Kern Sibbald and John Walker
+ Copyright (C) 2000-2004 Kern Sibbald and John Walker
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
#include "bacula.h"
/* Forward referenced functions */
-static void *workq_server(void *arg);
+extern "C" void *workq_server(void *arg);
-/*
+/*
* Initialize a work queue
*
* Returns: 0 on success
* errno on failure
*/
-int workq_init(workq_t *wq, int threads, void (*engine)(void *arg))
+int workq_init(workq_t *wq, int threads, void *(*engine)(void *arg))
{
int stat;
-
+
if ((stat = pthread_attr_init(&wq->attr)) != 0) {
return stat;
}
wq->num_workers = 0; /* no threads yet */
wq->idle_workers = 0; /* no idle threads */
wq->engine = engine; /* routine to run */
- wq->valid = WORKQ_VALID;
+ wq->valid = WORKQ_VALID;
return 0;
}
}
wq->valid = 0; /* prevent any more operations */
- /*
- * If any threads are active, wake them
+ /*
+ * If any threads are active, wake them
*/
if (wq->num_workers > 0) {
wq->quit = 1;
/*
* Add work to a queue
+ * wq is a queue that was created with workq_init
+ * element is a user unique item that will be passed to the
+ * processing routine
+ * work_item will get internal work queue item -- if it is not NULL
+ * priority if non-zero will cause the item to be placed on the
+ * head of the list instead of the tail.
*/
-int workq_add(workq_t *wq, void *element)
+int workq_add(workq_t *wq, void *element, workq_ele_t **work_item, int priority)
{
int stat;
workq_ele_t *item;
pthread_t id;
-
- Dmsg0(200, "workq_add\n");
+
+ Dmsg0(1400, "workq_add\n");
if (wq->valid != WORKQ_VALID) {
return EINVAL;
}
- if ((item = (workq_ele_t *) malloc(sizeof(workq_ele_t))) == NULL) {
+ if ((item = (workq_ele_t *)malloc(sizeof(workq_ele_t))) == NULL) {
return ENOMEM;
}
item->data = element;
return stat;
}
- Dmsg0(200, "add item to queue\n");
- /* Add the new item to the end of the queue */
- if (wq->first == NULL) {
- wq->first = item;
+ Dmsg0(1400, "add item to queue\n");
+ if (priority) {
+ /* Add to head of queue */
+ if (wq->first == NULL) {
+ wq->first = item;
+ wq->last = item;
+ } else {
+ item->next = wq->first;
+ wq->first = item;
+ }
} else {
- wq->last->next = item;
+ /* Add to end of queue */
+ if (wq->first == NULL) {
+ wq->first = item;
+ } else {
+ wq->last->next = item;
+ }
+ wq->last = item;
}
- wq->last = item;
/* if any threads are idle, wake one */
if (wq->idle_workers > 0) {
- Dmsg0(200, "Signal worker\n");
+ Dmsg0(1400, "Signal worker\n");
if ((stat = pthread_cond_signal(&wq->work)) != 0) {
pthread_mutex_unlock(&wq->mutex);
return stat;
}
} else if (wq->num_workers < wq->max_workers) {
- Dmsg0(200, "Create worker thread\n");
+ Dmsg0(1400, "Create worker thread\n");
+ /* No idle threads so create a new one */
+ set_thread_concurrency(wq->max_workers + 1);
+ if ((stat = pthread_create(&id, &wq->attr, workq_server, (void *)wq)) != 0) {
+ pthread_mutex_unlock(&wq->mutex);
+ return stat;
+ }
+ wq->num_workers++;
+ }
+ pthread_mutex_unlock(&wq->mutex);
+ Dmsg0(1400, "Return workq_add\n");
+ /* Return work_item if requested */
+ if (work_item) {
+ *work_item = item;
+ }
+ return stat;
+}
+
+/*
+ * Remove work from a queue
+ * wq is a queue that was created with workq_init
+ * work_item is an element of work
+ *
+ * Note, it is "removed" by immediately calling a processing routine.
+ * if you want to cancel it, you need to provide some external means
+ * of doing so.
+ */
+int workq_remove(workq_t *wq, workq_ele_t *work_item)
+{
+ int stat, found = 0;
+ pthread_t id;
+ workq_ele_t *item, *prev;
+
+ Dmsg0(1400, "workq_remove\n");
+ if (wq->valid != WORKQ_VALID) {
+ return EINVAL;
+ }
+
+ if ((stat = pthread_mutex_lock(&wq->mutex)) != 0) {
+ return stat;
+ }
+
+ for (prev=item=wq->first; item; item=item->next) {
+ if (item == work_item) {
+ found = 1;
+ break;
+ }
+ prev = item;
+ }
+ if (!found) {
+ return EINVAL;
+ }
+
+ /* Move item to be first on list */
+ if (wq->first != work_item) {
+ prev->next = work_item->next;
+ if (wq->last == work_item) {
+ wq->last = prev;
+ }
+ work_item->next = wq->first;
+ wq->first = work_item;
+ }
+
+ /* if any threads are idle, wake one */
+ if (wq->idle_workers > 0) {
+ Dmsg0(1400, "Signal worker\n");
+ if ((stat = pthread_cond_signal(&wq->work)) != 0) {
+ pthread_mutex_unlock(&wq->mutex);
+ return stat;
+ }
+ } else {
+ Dmsg0(1400, "Create worker thread\n");
/* No idle threads so create a new one */
set_thread_concurrency(wq->max_workers + 1);
if ((stat = pthread_create(&id, &wq->attr, workq_server, (void *)wq)) != 0) {
wq->num_workers++;
}
pthread_mutex_unlock(&wq->mutex);
- Dmsg0(200, "Return workq_add\n");
+ Dmsg0(1400, "Return workq_remove\n");
return stat;
}
-/*
+
+/*
* This is the worker thread that serves the work queue.
* In due course, it will call the user's engine.
*/
-static void *workq_server(void *arg)
+extern "C"
+void *workq_server(void *arg)
{
struct timespec timeout;
workq_t *wq = (workq_t *)arg;
workq_ele_t *we;
int stat, timedout;
- Dmsg0(200, "Start workq_server\n");
+ Dmsg0(1400, "Start workq_server\n");
if ((stat = pthread_mutex_lock(&wq->mutex)) != 0) {
return NULL;
}
struct timeval tv;
struct timezone tz;
- Dmsg0(200, "Top of for loop\n");
+ Dmsg0(1400, "Top of for loop\n");
timedout = 0;
- Dmsg0(200, "gettimeofday()\n");
+ Dmsg0(1400, "gettimeofday()\n");
gettimeofday(&tv, &tz);
timeout.tv_nsec = 0;
timeout.tv_sec = tv.tv_sec + 2;
/*
* Wait 2 seconds, then if no more work, exit
*/
- Dmsg0(200, "pthread_cond_timedwait()\n");
+ Dmsg0(1400, "pthread_cond_timedwait()\n");
#ifdef xxxxxxxxxxxxxxxx_was_HAVE_CYGWIN
/* CYGWIN dies with a page fault the second
* time that pthread_cond_timedwait() is called
#else
stat = pthread_cond_timedwait(&wq->work, &wq->mutex, &timeout);
#endif
- Dmsg1(200, "timedwait=%d\n", stat);
+ Dmsg1(1400, "timedwait=%d\n", stat);
if (stat == ETIMEDOUT) {
timedout = 1;
break;
} else if (stat != 0) {
/* This shouldn't happen */
- Dmsg0(200, "This shouldn't happen\n");
+ Dmsg0(1400, "This shouldn't happen\n");
wq->num_workers--;
pthread_mutex_unlock(&wq->mutex);
return NULL;
}
- }
+ }
we = wq->first;
if (we != NULL) {
wq->first = we->next;
return NULL;
}
/* Call user's routine here */
- Dmsg0(200, "Calling user engine.\n");
+ Dmsg0(1400, "Calling user engine.\n");
wq->engine(we->data);
- Dmsg0(200, "Back from user engine.\n");
+ Dmsg0(1400, "Back from user engine.\n");
free(we); /* release work entry */
- Dmsg0(200, "relock mutex\n");
+ Dmsg0(1400, "relock mutex\n");
if ((stat = pthread_mutex_lock(&wq->mutex)) != 0) {
return NULL;
}
- Dmsg0(200, "Done lock mutex\n");
+ Dmsg0(1400, "Done lock mutex\n");
}
/*
* If no more work request, and we are asked to quit, then do it
if (wq->first == NULL && wq->quit) {
wq->num_workers--;
if (wq->num_workers == 0) {
- Dmsg0(200, "Wake up destroy routine\n");
+ Dmsg0(1400, "Wake up destroy routine\n");
/* Wake up destroy routine if he is waiting */
pthread_cond_broadcast(&wq->work);
}
- Dmsg0(200, "Unlock mutex\n");
+ Dmsg0(1400, "Unlock mutex\n");
pthread_mutex_unlock(&wq->mutex);
- Dmsg0(200, "Return from workq_server\n");
+ Dmsg0(1400, "Return from workq_server\n");
return NULL;
}
- Dmsg0(200, "Check for work request\n");
- /*
+ Dmsg0(1400, "Check for work request\n");
+ /*
* If no more work requests, and we waited long enough, quit
*/
- Dmsg1(200, "wq->first==NULL = %d\n", wq->first==NULL);
- Dmsg1(200, "timedout=%d\n", timedout);
+ Dmsg1(1400, "wq->first==NULL = %d\n", wq->first==NULL);
+ Dmsg1(1400, "timedout=%d\n", timedout);
if (wq->first == NULL && timedout) {
- Dmsg0(200, "break big loop\n");
+ Dmsg0(1400, "break big loop\n");
wq->num_workers--;
break;
}
- Dmsg0(200, "Loop again\n");
+ Dmsg0(1400, "Loop again\n");
} /* end of big for loop */
- Dmsg0(200, "unlock mutex\n");
+ Dmsg0(1400, "unlock mutex\n");
pthread_mutex_unlock(&wq->mutex);
- Dmsg0(200, "End workq_server\n");
+ Dmsg0(1400, "End workq_server\n");
return NULL;
}
projects / bacula / bacula / blobdiff