Changed the way we create aditional threads. One for every connection is

[citadel.git] / citadel / sysdep.c

diff --git a/citadel/sysdep.c b/citadel/sysdep.c
index 44cb747457c49c6145dbea00b45ea1cc89d3d8f2..6be3f2cca11739d35cabfda447d548cdc57bbcb3 100644 (file)
--- a/citadel/sysdep.c
+++ b/citadel/sysdep.c
@@ -1357,7 +1357,7 @@ int CtdlThreadCheckStop(struct CtdlThreadNode *this_thread)
                pthread_mutex_unlock(&this_thread->ThreadMutex);
                return -1;
        }
-       else if(this_thread->state < CTDL_THREAD_STOP_REQ)
+       else if((this_thread->state < CTDL_THREAD_STOP_REQ) && (this_thread->state > CTDL_THREAD_CREATE))
        {
                pthread_mutex_unlock(&this_thread->ThreadMutex);
                return -1;
@@ -1579,12 +1579,11 @@ void ctdl_internal_thread_gc (void)
        /* Sanity check number of worker threads */
        if (workers != num_workers)
        {
-               CtdlLogPrintf(CTDL_WARNING,
-                       "Thread system WARNING, discrepancy in number of worker threads. Counted %d, should be %d.\n",
+               CtdlLogPrintf(CTDL_EMERG,
+                       "Thread system PANIC, discrepancy in number of worker threads. Counted %d, should be %d.\n",
                        workers, num_workers
                        );
                abort();
-               return;
        }
 }
 
@@ -1606,9 +1605,17 @@ static void *ctdl_internal_thread_func (void *arg)
         * can continue its execution.
         */
        begin_critical_section(S_THREAD_LIST);
+       // Register the cleanup function to take care of when we exit.
+       pthread_cleanup_push(ctdl_internal_thread_cleanup, NULL);
        // Get our thread data structure
        this_thread = (struct CtdlThreadNode *) arg;
-       this_thread->state = CTDL_THREAD_RUNNING;
+       /* Only change to running state if we weren't asked to stop during the create cycle
+        * Other wise there is a window to allow this threads creation to continue to full grown and
+        * therby prevent a shutdown of the server.
+        */
+       if (!CtdlThreadCheckStop(this_thread))
+               this_thread->state = CTDL_THREAD_RUNNING;
+       
        this_thread->pid = getpid();
        gettimeofday(&this_thread->start_time, NULL);           /* Time this thread started */
        memcpy(&this_thread->last_state_change, &this_thread->start_time, sizeof (struct timeval));     /* Changed state so mark it. */
@@ -1617,14 +1624,13 @@ static void *ctdl_internal_thread_func (void *arg)
        // Tell the world we are here
        CtdlLogPrintf(CTDL_NOTICE, "Created a new thread \"%s\" (%ld). \n", this_thread->name, this_thread->tid);
 
-       // Register the cleanup function to take care of when we exit.
-       pthread_cleanup_push(ctdl_internal_thread_cleanup, NULL);
        
        
        /*
-        * run the thread to do the work
+        * run the thread to do the work but only if we haven't been asked to stop
         */
-       ret = (this_thread->thread_func)(this_thread->user_args);
+       if (!CtdlThreadCheckStop(this_thread))
+               ret = (this_thread->thread_func)(this_thread->user_args);
        
        /*
         * Our thread is exiting either because it wanted to end or because the server is stopping
@@ -1811,17 +1817,16 @@ void dead_session_purge(int force) {
        struct CitContext *ptr, *ptr2;          /* general-purpose utility pointer */
        struct CitContext *rem = NULL;  /* list of sessions to be destroyed */
        
-       CtdlThreadPushName("dead_session_purge");
-       
        if (force == 0) {
                if ( (time(NULL) - last_purge) < 5 ) {
-                       CtdlThreadPopName();
                        return; /* Too soon, go away */
                }
        }
        time(&last_purge);
 
-       begin_critical_section(S_SESSION_TABLE);
+       if (try_critical_section(S_SESSION_TABLE))
+               return;
+               
        ptr = ContextList;
        while (ptr) {
                ptr2 = ptr;
@@ -1840,11 +1845,9 @@ void dead_session_purge(int force) {
                        }
 
                        --num_sessions;
-
                        /* And put it on our to-be-destroyed list */
                        ptr2->next = rem;
                        rem = ptr2;
-
                }
        }
        end_critical_section(S_SESSION_TABLE);
@@ -1860,18 +1863,6 @@ void dead_session_purge(int force) {
                rem = rem->next;
                free(ptr);
        }
-
-       /* Raise the size of the worker thread pool if necessary. */
-       begin_critical_section(S_THREAD_LIST);
-       if ( (num_sessions > num_workers)
-          && (num_workers < config.c_max_workers) ) {
-               ctdl_internal_create_thread("Worker Thread", CTDLTHREAD_BIGSTACK + CTDLTHREAD_WORKER, worker_thread, NULL);
-       }
-       end_critical_section(S_THREAD_LIST);
-       // FIXME: reduce the number of worker threads too
-       
-       CtdlThreadPopName();
-       
 }
 
 
@@ -1973,7 +1964,6 @@ do_select:        force_purge = 0;
                        tv.tv_sec = 1;          /* wake up every second if no input */
                        tv.tv_usec = 0;
                        retval = CtdlThreadSelect(highest + 1, &readfds, NULL, NULL, &tv, CT);
-//                     retval = select(highest + 1, &readfds, NULL, NULL, &tv);
                }
 
                if (CtdlThreadCheckStop(CT)) return(NULL);
@@ -1995,9 +1985,9 @@ do_select:        force_purge = 0;
                                goto do_select;
                        }
                }
-               else if(retval == 0) {
-                       goto SKIP_SELECT;
-               }
+//             else if(retval == 0) {
+//                     goto SKIP_SELECT;
+//             }
                /* Next, check to see if it's a new client connecting
                 * on a master socket.
                 */
@@ -2103,7 +2093,6 @@ SKIP_SELECT:
 
                dead_session_purge(force_purge);
                do_housekeeping();
-               check_sched_shutdown();
        }
        /* If control reaches this point, the server is shutting down */        
        return(NULL);