struct CitContext masterCC;
int rescan[2]; /* The Rescan Pipe */
time_t last_purge = 0; /* Last dead session purge */
-int num_threads = 0; /* Current number of threads */
+static int num_threads = 0; /* Current number of threads */
int num_sessions = 0; /* Current number of sessions */
fd_set masterfds; /* Master sockets etc. */
time_t last_timer = 0L; /* Last timer hook processing */
+static pthread_t initial_thread; /* tid for main() thread */
+
/*
* lprintf() ... Write logging information
* that it's time to call master_cleanup() and exit.
*/
-static volatile int time_to_die = 0;
+volatile int time_to_die = 0;
static RETSIGTYPE signal_cleanup(int signum) {
time_to_die = 1;
}
}
+static struct worker_node {
+ pthread_t tid;
+ struct worker_node *next;
+} *worker_list = NULL;
+
+
+/*
+ * create a worker thread. this function must always be called from within
+ * an S_WORKER_LIST critical section!
+ */
+static void create_worker(void) {
+ int ret;
+ struct worker_node *n = mallok(sizeof *n);
+
+ if (n == NULL) {
+ lprintf(1, "can't allocate worker_node, exiting\n");
+ time_to_die = -1;
+ return;
+ }
+
+ if ((ret = pthread_create(&n->tid, NULL, worker_thread, NULL) != 0))
+ {
+
+ lprintf(1, "Can't create worker thread: %s\n",
+ strerror(ret));
+ }
+
+ n->next = worker_list;
+ worker_list = n;
+}
+
/*
*/
void dead_session_purge(void) {
struct CitContext *ptr, *rem;
- pthread_attr_t attr;
- pthread_t newthread;
+ struct worker_node **node, *tmp;
+ pthread_t self;
if ( (time(NULL) - last_purge) < 5 ) return; /* Too soon, go away */
time(&last_purge);
* an action is appropriate.
*/
+ self = pthread_self();
+
if ( (num_sessions > num_threads)
&& (num_threads < config.c_max_workers) ) {
-
- pthread_attr_init(&attr);
- pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
- if (pthread_create(&newthread, &attr,
- (void* (*)(void*)) worker_thread, NULL) != 0) {
- lprintf(1, "Can't create worker thead: %s\n",
- strerror(errno));
- }
-
+ begin_critical_section(S_WORKER_LIST);
+ create_worker();
+ end_critical_section(S_WORKER_LIST);
}
+ /* don't let the initial thread die since it's responsible for
+ waiting for all the other threads to terminate. */
else if ( (num_sessions < num_threads)
- && (num_threads > config.c_min_workers) ) {
+ && (num_threads > config.c_min_workers)
+ && (self != initial_thread) ) {
+ cdb_free_tsd();
+ begin_critical_section(S_WORKER_LIST);
--num_threads;
+
+ /* we're exiting before server shutdown... unlink ourself from
+ the worker list and detach our thread to avoid memory leaks
+ */
+
+ for (node = &worker_list; *node != NULL; node = &(*node)->next)
+ if ((*node)->tid == self) {
+ tmp = *node;
+ *node = (*node)->next;
+ phree(tmp);
+ break;
+ }
+
+ pthread_detach(self);
+ end_critical_section(S_WORKER_LIST);
pthread_exit(NULL);
}
*/
int main(int argc, char **argv)
{
- pthread_t WorkerThread; /* Thread descriptor */
- pthread_attr_t attr; /* Thread attributes */
char tracefile[128]; /* Name of file to log traces to */
int a, i; /* General-purpose variables */
struct passwd *pw;
int drop_root_perms = 1;
char *moddir;
+ struct worker_node *wnp;
/* specify default port name and trace file */
strcpy(tracefile, "");
/* We want to check for idle sessions once per minute */
CtdlRegisterSessionHook(terminate_idle_sessions, EVT_TIMER);
-
+
/*
* Now create a bunch of worker threads.
*/
+ lprintf(9, "Starting %d worker threads\n", config.c_min_workers-1);
+ begin_critical_section(S_WORKER_LIST);
for (i=0; i<(config.c_min_workers-1); ++i) {
- lprintf(9, "Creating worker thread %d\n", i);
- pthread_attr_init(&attr);
- pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
- if (pthread_create(&WorkerThread, &attr,
- (void* (*)(void*)) worker_thread, NULL) != 0) {
- lprintf(1, "Can't create worker thead: %s\n",
- strerror(errno));
- }
+ create_worker();
}
-
+ end_critical_section(S_WORKER_LIST);
/* Now this thread can become a worker as well. */
- lprintf(9, "Original thread entering worker loop\n");
- worker_thread();
+ initial_thread = pthread_self();
+ worker_thread(NULL);
+
+ /* Server is exiting. Wait for workers to shutdown. */
+ lprintf(7, "Waiting for worker threads to shut down\n");
+
+ begin_critical_section(S_WORKER_LIST);
+ while (worker_list != NULL) {
+ wnp = worker_list;
+ worker_list = wnp->next;
+
+ /* avoid deadlock with an exiting thread */
+ end_critical_section(S_WORKER_LIST);
+ if ((i = pthread_join(wnp->tid, NULL)))
+ lprintf(1, "pthread_join: %s\n", strerror(i));
+ phree(wnp);
+ begin_critical_section(S_WORKER_LIST);
+ }
+ end_critical_section(S_WORKER_LIST);
+
+ master_cleanup();
return(0);
}
/*
* This loop just keeps going and going and going...
*/
-void worker_thread(void) {
+void *worker_thread(void *arg) {
int i;
char junk;
int highest;
int ssock; /* Descriptor for client socket */
struct timeval tv;
- ++num_threads;
+ num_threads++;
+
+ cdb_allocate_tsd();
while (!time_to_die) {
* context we want and go on our merry way.
*/
+ /* make doubly sure we're not holding any stale db handles
+ * which might cause a deadlock.
+ */
+ cdb_release_handles();
+
begin_critical_section(S_I_WANNA_SELECT);
SETUP_FD: memcpy(&readfds, &masterfds, sizeof masterfds);
highest = masterhighest;
}
end_critical_section(S_SESSION_TABLE);
- tv.tv_sec = 60; /* wake up every minute if no input */
+ tv.tv_sec = 1; /* wake up every second if no input */
tv.tv_usec = 0;
- retval = select(highest + 1, &readfds, NULL, NULL, &tv);
+
+ do_select:
+ if (!time_to_die)
+ retval = select(highest + 1, &readfds, NULL, NULL, &tv);
+ else {
+ end_critical_section(S_I_WANNA_SELECT);
+ break;
+ }
/* Now figure out who made this select() unblock.
* First, check for an error or exit condition.
*/
if (retval < 0) {
- end_critical_section(S_I_WANNA_SELECT);
- lprintf(9, "Exiting (%s)\n", strerror(errno));
- time_to_die = 1;
+ if (errno != EINTR) {
+ lprintf(9, "Exiting (%s)\n", strerror(errno));
+ time_to_die = 1;
+ } else if (!time_to_die)
+ goto do_select;
}
/* Next, check to see if it's a new client connecting
* thread that the &readfds needs to be refreshed with more
* current data.
*/
- if (time_to_die)
+ if (time_to_die) {
+ end_critical_section(S_I_WANNA_SELECT);
break;
+ }
if (FD_ISSET(rescan[0], &readfds)) {
read(rescan[0], &junk, 1);
dead_session_purge();
if ((time(NULL) - last_timer) > 60L) {
last_timer = time(NULL);
+ cdb_release_handles(); /* suggested by Justin Case */
PerformSessionHooks(EVT_TIMER);
}
}
/* If control reaches this point, the server is shutting down */
- master_cleanup();
--num_threads;
- pthread_exit(NULL);
+ return NULL;
}
+
+
projects / citadel.git / commitdiff