mirror of
				https://github.com/asterisk/asterisk.git
				synced 2025-10-31 02:37:10 +00:00 
			
		
		
		
	Split caching out from the stasis_caching_topic.
In working with res_stasis, I discovered a significant limitation to
the current structure of stasis_caching_topics: you cannot subscribe
to cache updates for a single channel/bridge/endpoint/etc.
To address this, this patch splits the cache away from the
stasis_caching_topic, making it a first class object. The stasis_cache
object is shared amongst individual stasis_caching_topics that are
created per channel/endpoint/etc. These are still forwarded to global
whatever_all_cached topics, so their use from most of the code does
not change.
In making these changes, I noticed that we frequently used a similar
pattern for bridges, endpoints and channels:
     single_topic  ---------------->  all_topic
           ^
           |
     single_topic_cached  ----+---->  all_topic_cached
                              |
                              +---->  cache
This pattern was extracted as the 'Stasis Caching Pattern', defined in
stasis_caching_pattern.h. This avoids a lot of duplicate code between
the different domain objects.
Since the cache is now disassociated from its upstream caching topics,
this also necessitated a change to how the 'guaranteed' flag worked
for retrieving from a cache. The code for handling the caching
guarantee was extracted into a 'stasis_topic_wait' function, which
works for any stasis_topic.
(closes issue ASTERISK-22002)
Review: https://reviewboard.asterisk.org/r/2672/
git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@395954 65c4cc65-6c06-0410-ace0-fbb531ad65f3
			
			
This commit is contained in:
		| @@ -196,6 +196,7 @@ static ast_cond_t change_pending; | ||||
| struct stasis_subscription *devstate_message_sub; | ||||
|  | ||||
| static struct stasis_topic *device_state_topic_all; | ||||
| static struct stasis_cache *device_state_cache; | ||||
| static struct stasis_caching_topic *device_state_topic_cached; | ||||
| static struct stasis_topic_pool *device_state_topic_pool; | ||||
|  | ||||
| @@ -285,7 +286,7 @@ static enum ast_device_state devstate_cached(const char *device) | ||||
| 	RAII_VAR(struct stasis_message *, cached_msg, NULL, ao2_cleanup); | ||||
| 	struct ast_device_state_message *device_state; | ||||
|  | ||||
| 	cached_msg = stasis_cache_get(ast_device_state_topic_cached(), ast_device_state_message_type(), device); | ||||
| 	cached_msg = stasis_cache_get(ast_device_state_cache(), ast_device_state_message_type(), device); | ||||
| 	if (!cached_msg) { | ||||
| 		return AST_DEVICE_UNKNOWN; | ||||
| 	} | ||||
| @@ -586,7 +587,7 @@ static enum ast_device_state get_aggregate_state(char *device) | ||||
|  | ||||
| 	ast_devstate_aggregate_init(&aggregate); | ||||
|  | ||||
| 	cached = stasis_cache_dump(ast_device_state_topic_cached(), NULL); | ||||
| 	cached = stasis_cache_dump(ast_device_state_cache(), NULL); | ||||
|  | ||||
| 	ao2_callback_data(cached, OBJ_NODATA, devstate_change_aggregator_cb, &aggregate, device); | ||||
|  | ||||
| @@ -598,7 +599,7 @@ static int aggregate_state_changed(char *device, enum ast_device_state new_aggre | ||||
| 	RAII_VAR(struct stasis_message *, cached_aggregate_msg, NULL, ao2_cleanup); | ||||
| 	struct ast_device_state_message *cached_aggregate_device_state; | ||||
|  | ||||
| 	cached_aggregate_msg = stasis_cache_get(ast_device_state_topic_cached(), ast_device_state_message_type(), device); | ||||
| 	cached_aggregate_msg = stasis_cache_get(ast_device_state_cache(), ast_device_state_message_type(), device); | ||||
| 	if (!cached_aggregate_msg) { | ||||
| 		return 1; | ||||
| 	} | ||||
| @@ -719,9 +720,14 @@ struct stasis_topic *ast_device_state_topic_all(void) | ||||
| 	return device_state_topic_all; | ||||
| } | ||||
|  | ||||
| struct stasis_caching_topic *ast_device_state_topic_cached(void) | ||||
| struct stasis_cache *ast_device_state_cache(void) | ||||
| { | ||||
| 	return device_state_topic_cached; | ||||
| 	return device_state_cache; | ||||
| } | ||||
|  | ||||
| struct stasis_topic *ast_device_state_topic_cached(void) | ||||
| { | ||||
| 	return stasis_caching_get_topic(device_state_topic_cached); | ||||
| } | ||||
|  | ||||
| struct stasis_topic *ast_device_state_topic(const char *device) | ||||
| @@ -777,6 +783,8 @@ static void devstate_cleanup(void) | ||||
| 	devstate_message_sub = stasis_unsubscribe_and_join(devstate_message_sub); | ||||
| 	ao2_cleanup(device_state_topic_all); | ||||
| 	device_state_topic_all = NULL; | ||||
| 	ao2_cleanup(device_state_cache); | ||||
| 	device_state_cache = NULL; | ||||
| 	device_state_topic_cached = stasis_caching_unsubscribe_and_join(device_state_topic_cached); | ||||
| 	STASIS_MESSAGE_TYPE_CLEANUP(ast_device_state_message_type); | ||||
| 	ao2_cleanup(device_state_topic_pool); | ||||
| @@ -794,7 +802,11 @@ int devstate_init(void) | ||||
| 	if (!device_state_topic_all) { | ||||
| 		return -1; | ||||
| 	} | ||||
| 	device_state_topic_cached = stasis_caching_topic_create(device_state_topic_all, device_state_get_id); | ||||
| 	device_state_cache = stasis_cache_create(device_state_get_id); | ||||
| 	if (!device_state_cache) { | ||||
| 		return -1; | ||||
| 	} | ||||
| 	device_state_topic_cached = stasis_caching_topic_create(device_state_topic_all, device_state_cache); | ||||
| 	if (!device_state_topic_cached) { | ||||
| 		return -1; | ||||
| 	} | ||||
| @@ -803,7 +815,7 @@ int devstate_init(void) | ||||
| 		return -1; | ||||
| 	} | ||||
|  | ||||
| 	devstate_message_sub = stasis_subscribe(stasis_caching_get_topic(ast_device_state_topic_cached()), devstate_change_collector_cb, NULL); | ||||
| 	devstate_message_sub = stasis_subscribe(ast_device_state_topic_cached(), devstate_change_collector_cb, NULL); | ||||
|  | ||||
| 	if (!devstate_message_sub) { | ||||
| 		ast_log(LOG_ERROR, "Failed to create subscription for the device state change collector\n"); | ||||
|   | ||||
		Reference in New Issue
	
	Block a user