Merge "pbx: Deadlock between contexts container and context_merge locks" into 11

changes/97/1997/1
Joshua Colp 9 years ago committed by Gerrit Code Review
commit 33407a66c4

@ -60,8 +60,10 @@ enum ast_event_type {
AST_EVENT_ACL_CHANGE = 0x0b,
/*! Send out a ping for debugging distributed events */
AST_EVENT_PING = 0x0c,
/*! Used to alert listeners when a hint has changed. */
AST_EVENT_HINT_CHANGE = 0x0d,
/*! Number of event types. This should be the last event type + 1 */
AST_EVENT_TOTAL = 0x0d,
AST_EVENT_TOTAL = 0x0e,
};
/*! \brief Event Information Element types */
@ -304,8 +306,16 @@ enum ast_event_ie_type {
* Payload type: UINT
*/
AST_EVENT_IE_CACHABLE = 0x003d,
/*!
* \brief Event hint change payload
* Used by: AST_EVENT_HINT_CHANGE
* Payload type: RAW
*/
AST_EVENT_IE_HINT_CHANGE_PAYLOAD = 0x003e,
/*! \brief Must be the last IE value +1 */
AST_EVENT_IE_TOTAL = 0x003e,
AST_EVENT_IE_TOTAL = 0x003f,
};
/*!

@ -1377,6 +1377,8 @@ static char *overrideswitch = NULL;
static struct ast_event_sub *device_state_sub;
/*! \brief Subscription for presence state change events */
static struct ast_event_sub *presence_state_sub;
/*! \brief Subscription for hint change events */
static struct ast_event_sub *hint_change_sub;
AST_MUTEX_DEFINE_STATIC(maxcalllock);
static int countcalls;
@ -5300,55 +5302,45 @@ static int execute_state_callback(ast_state_cb_type cb,
return res;
}
static int handle_presencechange(void *datap)
static void presence_state_notify_callbacks(enum ast_event_type type, struct ast_hint *hint,
struct ast_str **hint_app, struct presencechange *pc)
{
struct ast_hint *hint;
struct ast_str *hint_app = NULL;
struct presencechange *pc = datap;
struct ao2_iterator i;
struct ao2_iterator cb_iter;
struct ast_state_cb *state_cb;
char context_name[AST_MAX_CONTEXT];
char exten_name[AST_MAX_EXTENSION];
int res = -1;
hint_app = ast_str_create(1024);
if (!hint_app) {
goto presencechange_cleanup;
}
ast_mutex_lock(&context_merge_lock);/* Hold off ast_merge_contexts_and_delete */
i = ao2_iterator_init(hints, 0);
for (; (hint = ao2_iterator_next(&i)); ao2_ref(hint, -1)) {
struct ast_state_cb *state_cb;
const char *app;
char *parse;
ao2_lock(hint);
if (!hint->exten) {
/* The extension has already been destroyed */
ao2_unlock(hint);
continue;
return;
}
if (type != AST_EVENT_HINT_CHANGE) {
const char *app;
char *parse;
/* Does this hint monitor the device that changed state? */
app = ast_get_extension_app(hint->exten);
if (ast_strlen_zero(app)) {
/* The hint does not monitor presence at all. */
ao2_unlock(hint);
continue;
return;
}
ast_str_set(&hint_app, 0, "%s", app);
parse = parse_hint_presence(hint_app);
ast_str_set(hint_app, 0, "%s", app);
parse = parse_hint_presence(*hint_app);
if (ast_strlen_zero(parse)) {
ao2_unlock(hint);
continue;
return;
}
if (strcasecmp(parse, pc->provider)) {
/* The hint does not monitor the presence provider. */
ao2_unlock(hint);
continue;
return;
}
}
/*
@ -5360,16 +5352,19 @@ static int handle_presencechange(void *datap)
sizeof(context_name));
ast_copy_string(exten_name, ast_get_extension_name(hint->exten),
sizeof(exten_name));
ast_str_set(&hint_app, 0, "%s", ast_get_extension_app(hint->exten));
ast_str_set(hint_app, 0, "%s", ast_get_extension_app(hint->exten));
/* Check to see if update is necessary */
if ((hint->last_presence_state == pc->state) &&
((hint->last_presence_subtype && pc->subtype && !strcmp(hint->last_presence_subtype, pc->subtype)) || (!hint->last_presence_subtype && !pc->subtype)) &&
((hint->last_presence_message && pc->message && !strcmp(hint->last_presence_message, pc->message)) || (!hint->last_presence_message && !pc->message))) {
((hint->last_presence_subtype && pc->subtype &&
!strcmp(hint->last_presence_subtype, pc->subtype)) ||
(!hint->last_presence_subtype && !pc->subtype)) &&
((hint->last_presence_message && pc->message &&
!strcmp(hint->last_presence_message, pc->message)) ||
(!hint->last_presence_message && !pc->message))) {
/* this update is the same as the last, do nothing */
ao2_unlock(hint);
continue;
return;
}
/* update new values */
@ -5407,6 +5402,26 @@ static int handle_presencechange(void *datap)
}
ao2_iterator_destroy(&cb_iter);
}
static int handle_presencechange(void *datap)
{
struct presencechange *pc = datap;
struct ast_hint *hint;
struct ast_str *hint_app = NULL;
struct ao2_iterator i;
int res = -1;
hint_app = ast_str_create(1024);
if (!hint_app) {
goto presencechange_cleanup;
}
ast_mutex_lock(&context_merge_lock);/* Hold off ast_merge_contexts_and_delete */
i = ao2_iterator_init(hints, 0);
for (; (hint = ao2_iterator_next(&i)); ao2_ref(hint, -1)) {
presence_state_notify_callbacks(
AST_EVENT_PRESENCE_STATE, hint, &hint_app, pc);
}
ao2_iterator_destroy(&i);
ast_mutex_unlock(&context_merge_lock);
@ -5500,64 +5515,21 @@ static void get_device_state_causing_channels(struct ao2_container *c)
ao2_iterator_destroy(&iter);
}
static int handle_statechange(void *datap)
static void device_state_notify_callbacks(struct ast_hint *hint, struct ast_str **hint_app)
{
struct ast_hint *hint;
struct ast_str *hint_app;
struct ast_hintdevice *device;
struct ast_hintdevice *cmpdevice;
struct statechange *sc = datap;
struct ao2_iterator *dev_iter;
struct ao2_iterator cb_iter;
char context_name[AST_MAX_CONTEXT];
char exten_name[AST_MAX_EXTENSION];
if (ao2_container_count(hintdevices) == 0) {
/* There are no hints monitoring devices. */
ast_free(sc);
return 0;
}
hint_app = ast_str_create(1024);
if (!hint_app) {
ast_free(sc);
return -1;
}
cmpdevice = ast_alloca(sizeof(*cmpdevice) + strlen(sc->dev));
strcpy(cmpdevice->hintdevice, sc->dev);
ast_mutex_lock(&context_merge_lock);/* Hold off ast_merge_contexts_and_delete */
dev_iter = ao2_t_callback(hintdevices,
OBJ_POINTER | OBJ_MULTIPLE,
hintdevice_cmp_multiple,
cmpdevice,
"find devices in container");
if (!dev_iter) {
ast_mutex_unlock(&context_merge_lock);
ast_free(hint_app);
ast_free(sc);
return -1;
}
for (; (device = ao2_iterator_next(dev_iter)); ao2_t_ref(device, -1, "Next device")) {
struct ast_state_cb *state_cb;
int state;
int same_state;
int state, same_state;
struct ao2_container *device_state_info;
int first_extended_cb_call = 1;
if (!device->hint) {
/* Should never happen. */
continue;
}
hint = device->hint;
char context_name[AST_MAX_CONTEXT];
char exten_name[AST_MAX_EXTENSION];
ao2_lock(hint);
if (!hint->exten) {
/* The extension has already been destroyed */
ao2_unlock(hint);
continue;
return;
}
/*
@ -5569,7 +5541,7 @@ static int handle_statechange(void *datap)
sizeof(context_name));
ast_copy_string(exten_name, ast_get_extension_name(hint->exten),
sizeof(exten_name));
ast_str_set(&hint_app, 0, "%s", ast_get_extension_app(hint->exten));
ast_str_set(hint_app, 0, "%s", ast_get_extension_app(hint->exten));
ao2_unlock(hint);
/*
@ -5583,10 +5555,11 @@ static int handle_statechange(void *datap)
* If that failed we simply do not provide the extended state info.
*/
device_state_info = alloc_device_state_info();
state = ast_extension_state3(hint_app, device_state_info);
state = ast_extension_state3(*hint_app, device_state_info);
if ((same_state = state == hint->laststate) && (~state & AST_EXTENSION_RINGING)) {
ao2_cleanup(device_state_info);
continue;
return;
}
/* Device state changed since last check - notify the watchers. */
@ -5630,6 +5603,48 @@ static int handle_statechange(void *datap)
ao2_cleanup(device_state_info);
}
static int handle_statechange(void *datap)
{
struct statechange *sc = datap;
struct ast_str *hint_app;
struct ast_hintdevice *device;
struct ast_hintdevice *cmpdevice;
struct ao2_iterator *dev_iter;
if (ao2_container_count(hintdevices) == 0) {
/* There are no hints monitoring devices. */
ast_free(sc);
return 0;
}
hint_app = ast_str_create(1024);
if (!hint_app) {
ast_free(sc);
return -1;
}
cmpdevice = ast_alloca(sizeof(*cmpdevice) + strlen(sc->dev));
strcpy(cmpdevice->hintdevice, sc->dev);
ast_mutex_lock(&context_merge_lock);/* Hold off ast_merge_contexts_and_delete */
dev_iter = ao2_t_callback(hintdevices,
OBJ_POINTER | OBJ_MULTIPLE,
hintdevice_cmp_multiple,
cmpdevice,
"find devices in container");
if (!dev_iter) {
ast_mutex_unlock(&context_merge_lock);
ast_free(hint_app);
ast_free(sc);
return -1;
}
for (; (device = ao2_iterator_next(dev_iter)); ao2_t_ref(device, -1, "Next device")) {
if (device->hint) {
device_state_notify_callbacks(device->hint, &hint_app);
}
}
ast_mutex_unlock(&context_merge_lock);
ao2_iterator_destroy(dev_iter);
@ -5990,31 +6005,38 @@ static int ast_add_hint(struct ast_exten *e)
return 0;
}
/*! \brief Publish a hint changed event */
static int publish_hint_change(struct ast_hint *hint, struct ast_exten *ne)
{
struct ast_event *event;
/*
* Since hint is an ao2_object we need to pass in a pointer to the hint pointer,
* which gets copied by the event subsystem. The event handler will take care of
* de-referencing the hint.
*/
ao2_ref(hint, +1);
if (!(event = ast_event_new(AST_EVENT_HINT_CHANGE,
AST_EVENT_IE_HINT_CHANGE_PAYLOAD, AST_EVENT_IE_PLTYPE_RAW, &hint,
sizeof(hint), /* We actually want the size of the pointer */
AST_EVENT_IE_END))) {
ao2_ref(hint, -1);
return -1;
}
ast_event_queue_and_cache(event);
return 0;
}
/*! \brief Change hint for an extension */
static int ast_change_hint(struct ast_exten *oe, struct ast_exten *ne)
{
struct ast_str *hint_app;
struct ast_hint *hint;
int previous_device_state;
char *previous_message = NULL;
char *message = NULL;
char *previous_subtype = NULL;
char *subtype = NULL;
int previous_presence_state;
int presence_state;
int presence_state_changed = 0;
if (!oe || !ne) {
return -1;
}
hint_app = ast_str_create(1024);
if (!hint_app) {
return -1;
}
ast_mutex_lock(&context_merge_lock); /* Hold off ast_merge_contexts_and_delete and state changes */
ao2_lock(hints);/* Locked to hold off others while we move the hint around. */
/*
@ -6025,7 +6047,6 @@ static int ast_change_hint(struct ast_exten *oe, struct ast_exten *ne)
if (!hint) {
ao2_unlock(hints);
ast_mutex_unlock(&context_merge_lock);
ast_free(hint_app);
return -1;
}
@ -6035,25 +6056,6 @@ static int ast_change_hint(struct ast_exten *oe, struct ast_exten *ne)
ao2_lock(hint);
hint->exten = ne;
/* Store the previous states so we know whether we need to notify state callbacks */
previous_device_state = hint->laststate;
previous_presence_state = hint->last_presence_state;
previous_message = hint->last_presence_message;
previous_subtype = hint->last_presence_subtype;
/* Update the saved device and presence state with the new extension */
hint->laststate = ast_extension_state2(ne, NULL);
hint->last_presence_state = AST_PRESENCE_INVALID;
hint->last_presence_subtype = NULL;
hint->last_presence_message = NULL;
presence_state = extension_presence_state_helper(ne, &subtype, &message);
if (presence_state > 0) {
hint->last_presence_state = presence_state;
hint->last_presence_subtype = subtype;
hint->last_presence_message = message;
}
ao2_unlock(hint);
ao2_link(hints, hint);
@ -6062,103 +6064,59 @@ static int ast_change_hint(struct ast_exten *oe, struct ast_exten *ne)
ast_get_extension_name(ne),
ast_get_context_name(ast_get_extension_context(ne)));
}
ao2_unlock(hints);
/* Locking for state callbacks is respected here and only the context_merge_lock lock is
* held during the state callback invocation. This will stop the normal state callback
* thread from being able to handle incoming state changes if they occur.
*/
publish_hint_change(hint, ne);
ao2_ref(hint, -1);
/* Determine if presence state has changed due to the change of the hint extension */
if ((hint->last_presence_state != previous_presence_state) ||
strcmp(S_OR(hint->last_presence_subtype, ""), S_OR(previous_subtype, "")) ||
strcmp(S_OR(hint->last_presence_message, ""), S_OR(previous_message, ""))) {
presence_state_changed = 1;
return 0;
}
/* Notify any existing state callbacks if the device or presence state has changed */
if ((hint->laststate != previous_device_state) || presence_state_changed) {
struct ao2_iterator cb_iter;
struct ast_state_cb *state_cb;
struct ao2_container *device_state_info;
int first_extended_cb_call = 1;
static int handle_hint_change(void *data)
{
struct ast_hint *hint = data;
struct ast_str *hint_app;
int state;
struct presencechange presence_state;
/* For general callbacks */
cb_iter = ao2_iterator_init(statecbs, 0);
for (; (state_cb = ao2_iterator_next(&cb_iter)); ao2_ref(state_cb, -1)) {
/* Unlike the normal state callbacks since something has explicitly provided us this extension
* it will remain valid and unchanged for the lifetime of this function invocation.
*/
if (hint->laststate != previous_device_state) {
execute_state_callback(state_cb->change_cb,
ast_get_context_name(ast_get_extension_context(ne)),
ast_get_extension_name(ne),
state_cb->data,
AST_HINT_UPDATE_DEVICE,
hint,
NULL);
}
if (presence_state_changed) {
execute_state_callback(state_cb->change_cb,
ast_get_context_name(ast_get_extension_context(ne)),
ast_get_extension_name(ne),
state_cb->data,
AST_HINT_UPDATE_PRESENCE,
hint,
NULL);
}
if (!(hint_app = ast_str_create(1024))) {
return -1;
}
ao2_iterator_destroy(&cb_iter);
ast_str_set(&hint_app, 0, "%s", ast_get_extension_app(ne));
device_state_notify_callbacks(hint, &hint_app);
device_state_info = alloc_device_state_info();
ast_extension_state3(hint_app, device_state_info);
state = extension_presence_state_helper(
hint->exten, &presence_state.subtype, &presence_state.message);
/* For extension callbacks */
cb_iter = ao2_iterator_init(hint->callbacks, 0);
for (; (state_cb = ao2_iterator_next(&cb_iter)); ao2_ref(state_cb, -1)) {
if (hint->laststate != previous_device_state) {
if (state_cb->extended && first_extended_cb_call) {
/* Fill detailed device_state_info now that we know it is used by extd. callback */
first_extended_cb_call = 0;
get_device_state_causing_channels(device_state_info);
}
execute_state_callback(state_cb->change_cb,
ast_get_context_name(ast_get_extension_context(ne)),
ast_get_extension_name(ne),
state_cb->data,
AST_HINT_UPDATE_DEVICE,
hint,
state_cb->extended ? device_state_info : NULL);
}
if (presence_state_changed) {
execute_state_callback(state_cb->change_cb,
ast_get_context_name(ast_get_extension_context(ne)),
ast_get_extension_name(ne),
state_cb->data,
AST_HINT_UPDATE_PRESENCE,
hint,
NULL);
}
}
ao2_iterator_destroy(&cb_iter);
presence_state.state = state > 0 ? state : AST_PRESENCE_INVALID;
ao2_cleanup(device_state_info);
}
presence_state_notify_callbacks(AST_EVENT_HINT_CHANGE, hint, &hint_app, &presence_state);
ast_free(hint_app);
ao2_ref(hint, -1);
ast_mutex_unlock(&context_merge_lock);
ast_free(hint_app);
ast_free(previous_message);
ast_free(previous_subtype);
ast_free(presence_state.subtype);
ast_free(presence_state.message);
return 0;
}
static void hint_change_cb(const struct ast_event *event, void *unused)
{
/* The event data is a pointer to a hint (an ao2_object) */
struct ast_hint **hint = (struct ast_hint **)
ast_event_get_ie_raw(event, AST_EVENT_IE_HINT_CHANGE_PAYLOAD);
if (!hint || !*hint) {
return;
}
/* The task processor thread is taking our reference to the hint object. */
if (ast_taskprocessor_push(extension_state_tps, handle_hint_change, *hint) < 0) {
ao2_ref(*hint, -1);
}
}
/*! \brief Get hint for channel */
int ast_get_hint(char *hint, int hintsize, char *name, int namesize, struct ast_channel *c, const char *context, const char *exten)
@ -12255,6 +12213,9 @@ static void unload_pbx(void)
{
int x;
if (hint_change_sub) {
hint_change_sub = ast_event_unsubscribe(hint_change_sub);
}
if (presence_state_sub) {
presence_state_sub = ast_event_unsubscribe(presence_state_sub);
}
@ -12316,6 +12277,11 @@ int load_pbx(void)
return -1;
}
if (!(hint_change_sub = ast_event_subscribe(AST_EVENT_HINT_CHANGE, hint_change_cb, "pbx Hint Change", NULL,
AST_EVENT_IE_END))) {
return -1;
}
return 0;
}

Loading…
Cancel
Save