ITS#8901 tpool: use joinable threads instead of detached

When tearing down the threadpool we need to wait for the last
thread to actually exit, before returning. We can only wait
for a thread if it's joinable. For all the threads besides
the last one, we detach before exiting because we don't care
about waiting for them.

diff --git a/libraries/libldap/tpool.c b/libraries/libldap/tpool.c
index 00db4c359159ef63dd2e9ca08566a01b689f8689..9636a00d7990ced12e9c370937b2a43476378cd5 100644 (file)
--- a/libraries/libldap/tpool.c
+++ b/libraries/libldap/tpool.c
@@ -132,6 +132,9 @@ struct ldap_int_thread_poolq_s {
        int ltp_active_count;           /* Active, not paused/idle tasks */
        int ltp_open_count;                     /* Number of threads */
        int ltp_starting;                       /* Currently starting threads */
+
+       int ltp_last_valid;                     /* ltp_last was set */
+       ldap_pvt_thread_t ltp_last;     /* Last thread to exit */
 };
 
 struct ldap_int_thread_pool_s {
@@ -433,7 +436,7 @@ ldap_pvt_thread_pool_submit2 (
                pq->ltp_open_count++;
 
                if (0 != ldap_pvt_thread_create(
-                       &thr, 1, ldap_int_thread_pool_wrapper, pq))
+                       &thr, 0, ldap_int_thread_pool_wrapper, pq))
                {
                        /* couldn't create thread.  back out of
                         * ltp_open_count and check for even worse things.
@@ -894,6 +897,10 @@ ldap_pvt_thread_pool_close ( ldap_pvt_thread_pool_t *tpool, int run_pending )
                        LDAP_SLIST_REMOVE_HEAD(&pq->ltp_free_list, ltt_next.l);
                        LDAP_FREE(task);
                }
+               if (pq->ltp_last_valid) {
+                       pq->ltp_last_valid = 0;
+                       ldap_pvt_thread_join(pq->ltp_last, NULL);
+               }
                ldap_pvt_thread_mutex_unlock(&pq->ltp_mutex);
        }
 
@@ -1074,11 +1081,17 @@ ldap_int_thread_pool_wrapper (
 
        pq->ltp_open_count--;
        if (pq->ltp_open_count == 0) {
-               if (pool->ltp_finishing)
+               if (pool->ltp_finishing) {
                        /* let pool_destroy know we're all done */
+                       pq->ltp_last = ctx.ltu_id;
+                       pq->ltp_last_valid = 1;
                        ldap_pvt_thread_cond_signal(&pq->ltp_cond);
-               else
+               } else {
+                       ldap_pvt_thread_detach(ctx.ltu_id);
                        freeme = 1;
+               }
+       } else {
+               ldap_pvt_thread_detach(ctx.ltu_id);
        }
 
        if (pool_lock)