/***
*** Task Manager.
***/
static void
dispatch(isc_taskmgr_t *manager) {
isc_task_t *task;
#ifndef ISC_PLATFORM_USETHREADS
unsigned int total_dispatch_count = 0;
isc_tasklist_t ready_tasks;
#endif /* ISC_PLATFORM_USETHREADS */
REQUIRE(VALID_MANAGER(manager));
/*
* Again we're trying to hold the lock for as short a time as possible
* and to do as little locking and unlocking as possible.
*
* In both while loops, the appropriate lock must be held before the
* while body starts. Code which acquired the lock at the top of
* the loop would be more readable, but would result in a lot of
* extra locking. Compare:
*
* Straightforward:
*
* LOCK();
* ...
* UNLOCK();
* while (expression) {
* LOCK();
* ...
* UNLOCK();
*
* Unlocked part here...
*
* LOCK();
* ...
* UNLOCK();
* }
*
* Note how if the loop continues we unlock and then immediately lock.
* For N iterations of the loop, this code does 2N+1 locks and 2N+1
* unlocks. Also note that the lock is not held when the while
* condition is tested, which may or may not be important, depending
* on the expression.
*
* As written:
*
* LOCK();
* while (expression) {
* ...
* UNLOCK();
*
* Unlocked part here...
*
* LOCK();
* ...
* }
* UNLOCK();
*
* For N iterations of the loop, this code does N+1 locks and N+1
* unlocks. The while expression is always protected by the lock.
*/
#ifndef ISC_PLATFORM_USETHREADS
ISC_LIST_INIT(ready_tasks);
#endif
LOCK(&manager->lock);
while (!FINISHED(manager)) {
#ifdef ISC_PLATFORM_USETHREADS
/*
* For reasons similar to those given in the comment in
* isc_task_send() above, it is safe for us to dequeue
* the task while only holding the manager lock, and then
* change the task to running state while only holding the
* task lock.
*/
while ((EMPTY(manager->ready_tasks) ||
manager->exclusive_requested) &&
!FINISHED(manager))
{
XTHREADTRACE(isc_msgcat_get(isc_msgcat,
ISC_MSGSET_GENERAL,
ISC_MSG_WAIT, "wait"));
WAIT(&manager->work_available, &manager->lock);
XTHREADTRACE(isc_msgcat_get(isc_msgcat,
ISC_MSGSET_TASK,
ISC_MSG_AWAKE, "awake"));
}
#else /* ISC_PLATFORM_USETHREADS */
if (total_dispatch_count >= DEFAULT_TASKMGR_QUANTUM ||
EMPTY(manager->ready_tasks))
break;
#endif /* ISC_PLATFORM_USETHREADS */
XTHREADTRACE(isc_msgcat_get(isc_msgcat, ISC_MSGSET_TASK,
ISC_MSG_WORKING, "working"));
task = HEAD(manager->ready_tasks);
if (task != NULL) {
unsigned int dispatch_count = 0;
isc_boolean_t done = ISC_FALSE;
isc_boolean_t requeue = ISC_FALSE;
isc_boolean_t finished = ISC_FALSE;
isc_event_t *event;
INSIST(VALID_TASK(task));
/*
* Note we only unlock the manager lock if we actually
* have a task to do. We must reacquire the manager
* lock before exiting the 'if (task != NULL)' block.
*/
DEQUEUE(manager->ready_tasks, task, ready_link);
manager->tasks_running++;
UNLOCK(&manager->lock);
LOCK(&task->lock);
INSIST(task->state == task_state_ready);
task->state = task_state_running;
XTRACE(isc_msgcat_get(isc_msgcat, ISC_MSGSET_GENERAL,
ISC_MSG_RUNNING, "running"));
isc_stdtime_get(&task->now);
do {
if (!EMPTY(task->events)) {
event = HEAD(task->events);
DEQUEUE(task->events, event, ev_link);
/*
* Execute the event action.
*/
XTRACE(isc_msgcat_get(isc_msgcat,
ISC_MSGSET_TASK,
ISC_MSG_EXECUTE,
"execute action"));
if (event->ev_action != NULL) {
UNLOCK(&task->lock);
(event->ev_action)(task,event);
LOCK(&task->lock);
}
dispatch_count++;
#ifndef ISC_PLATFORM_USETHREADS
total_dispatch_count++;
#endif /* ISC_PLATFORM_USETHREADS */
}
if (task->references == 0 &&
EMPTY(task->events) &&
!TASK_SHUTTINGDOWN(task)) {
isc_boolean_t was_idle;
/*
* There are no references and no
* pending events for this task,
* which means it will not become
* runnable again via an external
* action (such as sending an event
* or detaching).
*
* We initiate shutdown to prevent
* it from becoming a zombie.
*
* We do this here instead of in
* the "if EMPTY(task->events)" block
* below because:
*
* If we post no shutdown events,
* we want the task to finish.
*
* If we did post shutdown events,
* will still want the task's
* quantum to be applied.
*/
was_idle = task_shutdown(task);
INSIST(!was_idle);
}
if (EMPTY(task->events)) {
/*
* Nothing else to do for this task
* right now.
*/
XTRACE(isc_msgcat_get(isc_msgcat,
ISC_MSGSET_TASK,
ISC_MSG_EMPTY,
"empty"));
if (task->references == 0 &&
TASK_SHUTTINGDOWN(task)) {
/*
* The task is done.
*/
XTRACE(isc_msgcat_get(
isc_msgcat,
ISC_MSGSET_TASK,
ISC_MSG_DONE,
"done"));
finished = ISC_TRUE;
task->state = task_state_done;
} else
task->state = task_state_idle;
done = ISC_TRUE;
} else if (dispatch_count >= task->quantum) {
/*
* Our quantum has expired, but
* there is more work to be done.
* We'll requeue it to the ready
* queue later.
*
* We don't check quantum until
* dispatching at least one event,
* so the minimum quantum is one.
*/
XTRACE(isc_msgcat_get(isc_msgcat,
ISC_MSGSET_TASK,
ISC_MSG_QUANTUM,
"quantum"));
task->state = task_state_ready;
requeue = ISC_TRUE;
done = ISC_TRUE;
}
} while (!done);
UNLOCK(&task->lock);
if (finished)
task_finished(task);
LOCK(&manager->lock);
manager->tasks_running--;
#ifdef ISC_PLATFORM_USETHREADS
if (manager->exclusive_requested &&
manager->tasks_running == 1) {
SIGNAL(&manager->exclusive_granted);
}
#endif /* ISC_PLATFORM_USETHREADS */
if (requeue) {
/*
* We know we're awake, so we don't have
* to wakeup any sleeping threads if the
* ready queue is empty before we requeue.
*
* A possible optimization if the queue is
* empty is to 'goto' the 'if (task != NULL)'
* block, avoiding the ENQUEUE of the task
* and the subsequent immediate DEQUEUE
* (since it is the only executable task).
* We don't do this because then we'd be
* skipping the exit_requested check. The
* cost of ENQUEUE is low anyway, especially
* when you consider that we'd have to do
* an extra EMPTY check to see if we could
* do the optimization. If the ready queue
* were usually nonempty, the 'optimization'
* might even hurt rather than help.
*/
#ifdef ISC_PLATFORM_USETHREADS
ENQUEUE(manager->ready_tasks, task,
ready_link);
#else
ENQUEUE(ready_tasks, task, ready_link);
#endif
}
}
}
#ifndef ISC_PLATFORM_USETHREADS
ISC_LIST_APPENDLIST(manager->ready_tasks, ready_tasks, ready_link);
#endif
UNLOCK(&manager->lock);
}
isc_result_t
ns_controls_configure(ns_controls_t *cp, const cfg_obj_t *config,
cfg_aclconfctx_t *aclconfctx)
{
controllistener_t *listener;
controllistenerlist_t new_listeners;
const cfg_obj_t *controlslist = NULL;
const cfg_listelt_t *element, *element2;
char socktext[ISC_SOCKADDR_FORMATSIZE];
ISC_LIST_INIT(new_listeners);
/*
* Get the list of named.conf 'controls' statements.
*/
(void)cfg_map_get(config, "controls", &controlslist);
/*
* Run through the new control channel list, noting sockets that
* are already being listened on and moving them to the new list.
*
* Identifying duplicate addr/port combinations is left to either
* the underlying config code, or to the bind attempt getting an
* address-in-use error.
*/
if (controlslist != NULL) {
for (element = cfg_list_first(controlslist);
element != NULL;
element = cfg_list_next(element)) {
const cfg_obj_t *controls;
const cfg_obj_t *inetcontrols = NULL;
controls = cfg_listelt_value(element);
(void)cfg_map_get(controls, "inet", &inetcontrols);
if (inetcontrols == NULL)
continue;
for (element2 = cfg_list_first(inetcontrols);
element2 != NULL;
element2 = cfg_list_next(element2)) {
const cfg_obj_t *control;
const cfg_obj_t *obj;
isc_sockaddr_t addr;
/*
* The parser handles BIND 8 configuration file
* syntax, so it allows unix phrases as well
* inet phrases with no keys{} clause.
*/
control = cfg_listelt_value(element2);
obj = cfg_tuple_get(control, "address");
addr = *cfg_obj_assockaddr(obj);
if (isc_sockaddr_getport(&addr) == 0)
isc_sockaddr_setport(&addr,
NS_CONTROL_PORT);
isc_sockaddr_format(&addr, socktext,
sizeof(socktext));
isc_log_write(ns_g_lctx,
NS_LOGCATEGORY_GENERAL,
NS_LOGMODULE_CONTROL,
ISC_LOG_DEBUG(9),
"processing control channel %s",
socktext);
update_listener(cp, &listener, control, config,
&addr, aclconfctx, socktext,
isc_sockettype_tcp);
if (listener != NULL)
/*
* Remove the listener from the old
* list, so it won't be shut down.
*/
ISC_LIST_UNLINK(cp->listeners,
listener, link);
else
/*
* This is a new listener.
*/
add_listener(cp, &listener, control,
config, &addr, aclconfctx,
socktext,
isc_sockettype_tcp);
if (listener != NULL)
ISC_LIST_APPEND(new_listeners,
listener, link);
}
}
for (element = cfg_list_first(controlslist);
element != NULL;
element = cfg_list_next(element)) {
const cfg_obj_t *controls;
const cfg_obj_t *unixcontrols = NULL;
controls = cfg_listelt_value(element);
(void)cfg_map_get(controls, "unix", &unixcontrols);
if (unixcontrols == NULL)
continue;
for (element2 = cfg_list_first(unixcontrols);
element2 != NULL;
element2 = cfg_list_next(element2)) {
const cfg_obj_t *control;
const cfg_obj_t *path;
isc_sockaddr_t addr;
isc_result_t result;
/*
* The parser handles BIND 8 configuration file
* syntax, so it allows unix phrases as well
* inet phrases with no keys{} clause.
*/
control = cfg_listelt_value(element2);
path = cfg_tuple_get(control, "path");
result = isc_sockaddr_frompath(&addr,
cfg_obj_asstring(path));
if (result != ISC_R_SUCCESS) {
isc_log_write(ns_g_lctx,
NS_LOGCATEGORY_GENERAL,
NS_LOGMODULE_CONTROL,
ISC_LOG_DEBUG(9),
"control channel '%s': %s",
cfg_obj_asstring(path),
isc_result_totext(result));
continue;
}
isc_log_write(ns_g_lctx,
NS_LOGCATEGORY_GENERAL,
NS_LOGMODULE_CONTROL,
ISC_LOG_DEBUG(9),
"processing control channel '%s'",
cfg_obj_asstring(path));
update_listener(cp, &listener, control, config,
&addr, aclconfctx,
cfg_obj_asstring(path),
isc_sockettype_unix);
if (listener != NULL)
/*
* Remove the listener from the old
* list, so it won't be shut down.
*/
ISC_LIST_UNLINK(cp->listeners,
listener, link);
else
/*
* This is a new listener.
*/
add_listener(cp, &listener, control,
config, &addr, aclconfctx,
cfg_obj_asstring(path),
isc_sockettype_unix);
if (listener != NULL)
ISC_LIST_APPEND(new_listeners,
listener, link);
}
}
} else {
int i;
for (i = 0; i < 2; i++) {
isc_sockaddr_t addr;
if (i == 0) {
struct in_addr localhost;
if (isc_net_probeipv4() != ISC_R_SUCCESS)
continue;
localhost.s_addr = htonl(INADDR_LOOPBACK);
isc_sockaddr_fromin(&addr, &localhost, 0);
} else {
if (isc_net_probeipv6() != ISC_R_SUCCESS)
continue;
isc_sockaddr_fromin6(&addr,
&in6addr_loopback, 0);
}
isc_sockaddr_setport(&addr, NS_CONTROL_PORT);
isc_sockaddr_format(&addr, socktext, sizeof(socktext));
update_listener(cp, &listener, NULL, NULL,
&addr, NULL, socktext,
isc_sockettype_tcp);
if (listener != NULL)
/*
* Remove the listener from the old
* list, so it won't be shut down.
*/
ISC_LIST_UNLINK(cp->listeners,
listener, link);
else
/*
* This is a new listener.
*/
add_listener(cp, &listener, NULL, NULL,
&addr, NULL, socktext,
isc_sockettype_tcp);
if (listener != NULL)
ISC_LIST_APPEND(new_listeners,
listener, link);
}
}
/*
* ns_control_shutdown() will stop whatever is on the global
* listeners list, which currently only has whatever sockaddrs
* were in the previous configuration (if any) that do not
* remain in the current configuration.
*/
controls_shutdown(cp);
/*
* Put all of the valid listeners on the listeners list.
* Anything already on listeners in the process of shutting
* down will be taken care of by listen_done().
*/
ISC_LIST_APPENDLIST(cp->listeners, new_listeners, link);
return (ISC_R_SUCCESS);
}
isc_result_t
ns_lwresd_configure(isc_mem_t *mctx, const cfg_obj_t *config) {
const cfg_obj_t *lwreslist = NULL;
const cfg_obj_t *lwres = NULL;
const cfg_obj_t *listenerslist = NULL;
const cfg_listelt_t *element = NULL;
ns_lwreslistener_t *listener;
ns_lwreslistenerlist_t newlisteners;
isc_result_t result;
char socktext[ISC_SOCKADDR_FORMATSIZE];
isc_sockaddr_t *addrs = NULL;
ns_lwresd_t *lwresd = NULL;
isc_uint32_t count = 0;
REQUIRE(mctx != NULL);
REQUIRE(config != NULL);
RUNTIME_CHECK(isc_once_do(&once, initialize_mutex) == ISC_R_SUCCESS);
ISC_LIST_INIT(newlisteners);
result = cfg_map_get(config, "lwres", &lwreslist);
if (result != ISC_R_SUCCESS)
return (ISC_R_SUCCESS);
LOCK(&listeners_lock);
/*
* Run through the new lwres address list, noting sockets that
* are already being listened on and moving them to the new list.
*
* Identifying duplicates addr/port combinations is left to either
* the underlying config code, or to the bind attempt getting an
* address-in-use error.
*/
for (element = cfg_list_first(lwreslist);
element != NULL;
element = cfg_list_next(element))
{
in_port_t port;
lwres = cfg_listelt_value(element);
CHECK(ns_lwdmanager_create(mctx, lwres, &lwresd));
port = lwresd_g_listenport;
if (port == 0)
port = LWRES_UDP_PORT;
listenerslist = NULL;
(void)cfg_map_get(lwres, "listen-on", &listenerslist);
if (listenerslist == NULL) {
struct in_addr localhost;
isc_sockaddr_t address;
localhost.s_addr = htonl(INADDR_LOOPBACK);
isc_sockaddr_fromin(&address, &localhost, port);
CHECK(configure_listener(&address, lwresd, mctx,
&newlisteners));
} else {
isc_uint32_t i;
CHECK(ns_config_getiplist(config, listenerslist,
port, mctx, &addrs, &count));
for (i = 0; i < count; i++)
CHECK(configure_listener(&addrs[i], lwresd,
mctx, &newlisteners));
ns_config_putiplist(mctx, &addrs, count);
}
ns_lwdmanager_detach(&lwresd);
}
/*
* Shutdown everything on the listeners list, and remove them from
* the list. Then put all of the new listeners on it.
*/
while (!ISC_LIST_EMPTY(listeners)) {
listener = ISC_LIST_HEAD(listeners);
ISC_LIST_UNLINK(listeners, listener, link);
isc_sockaddr_format(&listener->address,
socktext, sizeof(socktext));
listener_shutdown(listener);
ns_lwreslistener_detach(&listener);
isc_log_write(ns_g_lctx, ISC_LOGCATEGORY_GENERAL,
NS_LOGMODULE_LWRESD, ISC_LOG_NOTICE,
"lwres no longer listening on %s", socktext);
}
cleanup:
ISC_LIST_APPENDLIST(listeners, newlisteners, link);
if (addrs != NULL)
ns_config_putiplist(mctx, &addrs, count);
if (lwresd != NULL)
ns_lwdmanager_detach(&lwresd);
UNLOCK(&listeners_lock);
return (result);
}
isc_result_t
ns_statschannels_configure(ns_server_t *server, const cfg_obj_t *config,
cfg_aclconfctx_t *aclconfctx)
{
ns_statschannel_t *listener, *listener_next;
ns_statschannellist_t new_listeners;
const cfg_obj_t *statschannellist = NULL;
const cfg_listelt_t *element, *element2;
char socktext[ISC_SOCKADDR_FORMATSIZE];
RUNTIME_CHECK(isc_once_do(&once, init_desc) == ISC_R_SUCCESS);
ISC_LIST_INIT(new_listeners);
/*
* Get the list of named.conf 'statistics-channels' statements.
*/
(void)cfg_map_get(config, "statistics-channels", &statschannellist);
/*
* Run through the new address/port list, noting sockets that are
* already being listened on and moving them to the new list.
*
* Identifying duplicate addr/port combinations is left to either
* the underlying config code, or to the bind attempt getting an
* address-in-use error.
*/
if (statschannellist != NULL) {
#ifndef HAVE_LIBXML2
isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
NS_LOGMODULE_SERVER, ISC_LOG_WARNING,
"statistics-channels specified but not effective "
"due to missing XML library");
#endif
for (element = cfg_list_first(statschannellist);
element != NULL;
element = cfg_list_next(element)) {
const cfg_obj_t *statschannel;
const cfg_obj_t *listenercfg = NULL;
statschannel = cfg_listelt_value(element);
(void)cfg_map_get(statschannel, "inet",
&listenercfg);
if (listenercfg == NULL)
continue;
for (element2 = cfg_list_first(listenercfg);
element2 != NULL;
element2 = cfg_list_next(element2)) {
const cfg_obj_t *listen_params;
const cfg_obj_t *obj;
isc_sockaddr_t addr;
listen_params = cfg_listelt_value(element2);
obj = cfg_tuple_get(listen_params, "address");
addr = *cfg_obj_assockaddr(obj);
if (isc_sockaddr_getport(&addr) == 0)
isc_sockaddr_setport(&addr, NS_STATSCHANNEL_HTTPPORT);
isc_sockaddr_format(&addr, socktext,
sizeof(socktext));
isc_log_write(ns_g_lctx,
NS_LOGCATEGORY_GENERAL,
NS_LOGMODULE_SERVER,
ISC_LOG_DEBUG(9),
"processing statistics "
"channel %s",
socktext);
update_listener(server, &listener,
listen_params, config, &addr,
aclconfctx, socktext);
if (listener != NULL) {
/*
* Remove the listener from the old
* list, so it won't be shut down.
*/
ISC_LIST_UNLINK(server->statschannels,
listener, link);
} else {
/*
* This is a new listener.
*/
isc_result_t r;
r = add_listener(server, &listener,
listen_params, config,
&addr, aclconfctx,
socktext);
if (r != ISC_R_SUCCESS) {
cfg_obj_log(listen_params,
ns_g_lctx,
ISC_LOG_WARNING,
"couldn't allocate "
"statistics channel"
" %s: %s",
socktext,
isc_result_totext(r));
}
}
if (listener != NULL)
ISC_LIST_APPEND(new_listeners, listener,
link);
}
}
}
for (listener = ISC_LIST_HEAD(server->statschannels);
listener != NULL;
listener = listener_next) {
listener_next = ISC_LIST_NEXT(listener, link);
ISC_LIST_UNLINK(server->statschannels, listener, link);
shutdown_listener(listener);
}
ISC_LIST_APPENDLIST(server->statschannels, new_listeners, link);
return (ISC_R_SUCCESS);
}
