#include "portable.h"
#include <stdio.h>
-#include <stdarg.h>
+#include <ac/stdarg.h>
#include <ac/stdlib.h>
#include <ac/string.h>
#include <ac/time.h>
long ltp_pending_count;
long ltp_active_count;
long ltp_open_count;
+ long ltp_starting;
};
typedef struct ldap_int_thread_ctx_s {
static void *ldap_int_thread_enlist( ldap_int_thread_list_t *list, void *elem );
static void *ldap_int_thread_delist( ldap_int_thread_list_t *list, void *elem );
+#if 0
static void *ldap_int_thread_onlist( ldap_int_thread_list_t *list, void *elem );
+#endif
int
ldap_int_thread_pool_startup ( void )
int
ldap_pvt_thread_pool_init (
ldap_pvt_thread_pool_t *tpool,
- int max_concurrency,
+ int max_threads,
int max_pending )
{
- int rc;
ldap_pvt_thread_pool_t pool;
- ldap_pvt_thread_t thr;
+ int rc;
*tpool = NULL;
pool = (ldap_pvt_thread_pool_t) LDAP_CALLOC(1,
if (pool == NULL) return(-1);
- ldap_pvt_thread_mutex_init(&pool->ltp_mutex);
- ldap_pvt_thread_cond_init(&pool->ltp_cond);
+ rc = ldap_pvt_thread_mutex_init(&pool->ltp_mutex);
+ if (rc != 0)
+ return(rc);
+ rc = ldap_pvt_thread_cond_init(&pool->ltp_cond);
+ if (rc != 0)
+ return(rc);
pool->ltp_state = LDAP_INT_THREAD_POOL_RUNNING;
- pool->ltp_max_count = max_concurrency;
+ pool->ltp_max_count = max_threads;
pool->ltp_max_pending = max_pending;
ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
ldap_int_thread_enlist(&ldap_int_thread_pool_list, pool);
ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
- /* start up one thread, just so there is one */
+#if 0
+ /* THIS WILL NOT WORK on some systems. If the process
+ * forks after starting a thread, there is no guarantee
+ * that the thread will survive the fork. For example,
+ * slapd forks in order to daemonize, and does so after
+ * calling ldap_pvt_thread_pool_init. On some systems,
+ * this initial thread does not run in the child process,
+ * but ltp_open_count == 1, so two things happen:
+ * 1) the first client connection fails, and 2) when
+ * slapd is kill'ed, it never terminates since it waits
+ * for all worker threads to exit. */
+
+ /* start up one thread, just so there is one. no need to
+ * lock the mutex right now, since no threads are running.
+ */
pool->ltp_open_count++;
+ ldap_pvt_thread_t thr;
rc = ldap_pvt_thread_create( &thr, 1,
(void *) ldap_int_thread_pool_wrapper, pool );
free(pool);
return(-1);
}
+#endif
*tpool = pool;
return(0);
|| pool->ltp_open_count < pool->ltp_max_count))
{
pool->ltp_open_count++;
+ pool->ltp_starting++;
need_thread = 1;
}
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
if (need_thread) {
int rc = ldap_pvt_thread_create( &thr, 1,
(void *)ldap_int_thread_pool_wrapper, pool );
- if (rc != 0) {
+ ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
+ if (rc == 0) {
+ pool->ltp_starting--;
+ } else {
/* couldn't create thread. back out of
* ltp_open_count and check for even worse things.
*/
- ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
pool->ltp_open_count--;
+ pool->ltp_starting--;
if (pool->ltp_open_count == 0) {
- /* no open threads at all?!? this will never happen
- * because we always leave at least one thread open.
+ /* no open threads at all?!?
*/
if (ldap_int_thread_delist(&pool->ltp_pending_list, ctx)) {
/* no open threads, context not handled, so
return(-1);
}
}
- ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
/* there is another open thread, so this
* context will be handled eventually.
* continue on and signal that the context
* is waiting.
*/
}
+ ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
}
return(0);
}
+int
+ldap_pvt_thread_pool_maxthreads ( ldap_pvt_thread_pool_t *tpool, int max_threads )
+{
+ struct ldap_int_thread_pool_s *pool;
+
+ if (tpool == NULL)
+ return(-1);
+
+ pool = *tpool;
+
+ if (pool == NULL)
+ return(-1);
+
+ ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
+ pool->ltp_max_count = max_threads;
+ ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
+ return(0);
+}
+
int
ldap_pvt_thread_pool_backload ( ldap_pvt_thread_pool_t *tpool )
{
? LDAP_INT_THREAD_POOL_FINISHING
: LDAP_INT_THREAD_POOL_STOPPING;
waiting = pool->ltp_open_count;
- ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
/* broadcast could be used here, but only after
* it is fixed in the NT thread implementation
while (--waiting >= 0) {
ldap_pvt_thread_cond_signal(&pool->ltp_cond);
}
+ ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
do {
ldap_pvt_thread_yield();
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
} while (waiting > 0);
- while (ctx = (ldap_int_thread_ctx_t *)ldap_int_thread_delist(
- &pool->ltp_pending_list, NULL))
+ while ((ctx = (ldap_int_thread_ctx_t *)ldap_int_thread_delist(
+ &pool->ltp_pending_list, NULL)) != NULL)
{
free(ctx);
}
if (ctx == NULL) {
if (pool->ltp_state == LDAP_INT_THREAD_POOL_FINISHING)
break;
+ if (pool->ltp_max_count > 0
+ && pool->ltp_open_count > pool->ltp_max_count)
+ {
+ /* too many threads running (can happen if the
+ * maximum threads value is set during ongoing
+ * operation using ldap_pvt_thread_pool_maxthreads)
+ * so let this thread die.
+ */
+ break;
+ }
+
/* we could check an idle timer here, and let the
* thread die if it has been inactive for a while.
* only die if there are other open threads (i.e.,
- * always have at least one thread open).
+ * always have at least one thread open). the check
+ * should be like this:
+ * if (pool->ltp_open_count > 1 && pool->ltp_starting == 0)
+ * check timer, leave thread (break;)
*/
if (pool->ltp_state == LDAP_INT_THREAD_POOL_RUNNING)
}
return(NULL);
}
-
+#if 0
static void *
ldap_int_thread_onlist( ldap_int_thread_list_t *list, void *elem )
{
return(NULL);
}
-
+#endif
#endif /* LDAP_HAVE_THREAD_POOL */
projects / openldap / blobdiff