X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fust-app.c;h=d8adccde214925f2f9cd68d20ef65dadc3617951;hp=225d3f86a81a3837b4acbf9ed23c5d3cf01a9416;hb=7cc9a73c638bff0a86d7ea802ebd7fa3b4716ca9;hpb=6bb9e85f440e1ee6e54105b2f2c13035039ae64d diff --git a/src/bin/lttng-sessiond/ust-app.c b/src/bin/lttng-sessiond/ust-app.c index 225d3f86a..d8adccde2 100644 --- a/src/bin/lttng-sessiond/ust-app.c +++ b/src/bin/lttng-sessiond/ust-app.c @@ -17,6 +17,7 @@ #define _GNU_SOURCE #include +#include #include #include #include @@ -26,60 +27,64 @@ #include #include #include +#include #include #include +#include "buffer-registry.h" #include "fd-limit.h" -#include "health.h" +#include "health-sessiond.h" #include "ust-app.h" #include "ust-consumer.h" #include "ust-ctl.h" +#include "utils.h" -/* Next available channel key. */ -static unsigned long next_channel_key; +/* Next available channel key. Access under next_channel_key_lock. */ +static uint64_t _next_channel_key; +static pthread_mutex_t next_channel_key_lock = PTHREAD_MUTEX_INITIALIZER; + +/* Next available session ID. Access under next_session_id_lock. */ +static uint64_t _next_session_id; +static pthread_mutex_t next_session_id_lock = PTHREAD_MUTEX_INITIALIZER; /* - * Return the atomically incremented value of next_channel_key. + * Return the incremented value of next_channel_key. */ -static inline unsigned long get_next_channel_key(void) +static uint64_t get_next_channel_key(void) { - return uatomic_add_return(&next_channel_key, 1); + uint64_t ret; + + pthread_mutex_lock(&next_channel_key_lock); + ret = ++_next_channel_key; + pthread_mutex_unlock(&next_channel_key_lock); + return ret; } /* - * Return the consumer socket from the given consumer output with the right - * bitness. On error, returns NULL. - * - * The caller MUST acquire a rcu read side lock and keep it until the socket - * object reference is not needed anymore. + * Return the atomically incremented value of next_session_id. */ -static struct consumer_socket *find_consumer_socket_by_bitness(int bits, - struct consumer_output *consumer) +static uint64_t get_next_session_id(void) { - int consumer_fd; - struct consumer_socket *socket = NULL; - - switch (bits) { - case 64: - consumer_fd = uatomic_read(&ust_consumerd64_fd); - break; - case 32: - consumer_fd = uatomic_read(&ust_consumerd32_fd); - break; - default: - assert(0); - goto end; - } + uint64_t ret; - socket = consumer_find_socket(consumer_fd, consumer); - if (!socket) { - ERR("Consumer socket fd %d not found in consumer obj %p", - consumer_fd, consumer); - } + pthread_mutex_lock(&next_session_id_lock); + ret = ++_next_session_id; + pthread_mutex_unlock(&next_session_id_lock); + return ret; +} -end: - return socket; +static void copy_channel_attr_to_ustctl( + struct ustctl_consumer_channel_attr *attr, + struct lttng_ust_channel_attr *uattr) +{ + /* Copy event attributes since the layout is different. */ + attr->subbuf_size = uattr->subbuf_size; + attr->num_subbuf = uattr->num_subbuf; + attr->overwrite = uattr->overwrite; + attr->switch_timer_interval = uattr->switch_timer_interval; + attr->read_timer_interval = uattr->read_timer_interval; + attr->output = uattr->output; } /* @@ -99,7 +104,7 @@ static int ht_match_ust_app_event(struct cds_lfht_node *node, const void *_key) event = caa_container_of(node, struct ust_app_event, node.node); key = _key; - /* Match the 3 elements of the key: name, filter and loglevel. */ + /* Match the 4 elements of the key: name, filter, loglevel, exclusions */ /* Event name */ if (strncmp(event->attr.name, key->name, sizeof(event->attr.name)) != 0) { @@ -135,6 +140,21 @@ static int ht_match_ust_app_event(struct cds_lfht_node *node, const void *_key) } } + /* One of the exclusions is NULL, fail. */ + if ((key->exclusion && !event->exclusion) || (!key->exclusion && event->exclusion)) { + goto no_match; + } + + if (key->exclusion && event->exclusion) { + /* Both exclusions exists, check count followed by the names. */ + if (event->exclusion->count != key->exclusion->count || + memcmp(event->exclusion->names, key->exclusion->names, + event->exclusion->count * LTTNG_UST_SYM_NAME_LEN) != 0) { + goto no_match; + } + } + + /* Match. */ return 1; @@ -161,6 +181,7 @@ static void add_unique_ust_app_event(struct ust_app_channel *ua_chan, key.name = event->attr.name; key.filter = event->filter; key.loglevel = event->attr.loglevel; + key.exclusion = event->exclusion; node_ptr = cds_lfht_add_unique(ht->ht, ht->hash_fct(event->node.key, lttng_ht_seed), @@ -190,6 +211,48 @@ static void close_notify_sock_rcu(struct rcu_head *head) free(obj); } +/* + * Return the session registry according to the buffer type of the given + * session. + * + * A registry per UID object MUST exists before calling this function or else + * it assert() if not found. RCU read side lock must be acquired. + */ +static struct ust_registry_session *get_session_registry( + struct ust_app_session *ua_sess) +{ + struct ust_registry_session *registry = NULL; + + assert(ua_sess); + + switch (ua_sess->buffer_type) { + case LTTNG_BUFFER_PER_PID: + { + struct buffer_reg_pid *reg_pid = buffer_reg_pid_find(ua_sess->id); + if (!reg_pid) { + goto error; + } + registry = reg_pid->registry->reg.ust; + break; + } + case LTTNG_BUFFER_PER_UID: + { + struct buffer_reg_uid *reg_uid = buffer_reg_uid_find( + ua_sess->tracing_id, ua_sess->bits_per_long, ua_sess->uid); + if (!reg_uid) { + goto error; + } + registry = reg_uid->registry->reg.ust; + break; + } + default: + assert(0); + }; + +error: + return registry; +} + /* * Delete ust context safely. RCU read lock must be held before calling * this function. @@ -224,7 +287,8 @@ void delete_ust_app_event(int sock, struct ust_app_event *ua_event) assert(ua_event); free(ua_event->filter); - + if (ua_event->exclusion != NULL) + free(ua_event->exclusion); if (ua_event->obj != NULL) { ret = ustctl_release_object(sock, ua_event->obj); if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) { @@ -237,13 +301,13 @@ void delete_ust_app_event(int sock, struct ust_app_event *ua_event) } /* - * Delete ust app stream safely. RCU read lock must be held before calling - * this function. + * Release ust data object of the given stream. + * + * Return 0 on success or else a negative value. */ -static -void delete_ust_app_stream(int sock, struct ust_app_stream *stream) +static int release_ust_app_stream(int sock, struct ust_app_stream *stream) { - int ret; + int ret = 0; assert(stream); @@ -256,9 +320,40 @@ void delete_ust_app_stream(int sock, struct ust_app_stream *stream) lttng_fd_put(LTTNG_FD_APPS, 2); free(stream->obj); } + + return ret; +} + +/* + * Delete ust app stream safely. RCU read lock must be held before calling + * this function. + */ +static +void delete_ust_app_stream(int sock, struct ust_app_stream *stream) +{ + assert(stream); + + (void) release_ust_app_stream(sock, stream); free(stream); } +/* + * We need to execute ht_destroy outside of RCU read-side critical + * section and outside of call_rcu thread, so we postpone its execution + * using ht_cleanup_push. It is simpler than to change the semantic of + * the many callers of delete_ust_app_session(). + */ +static +void delete_ust_app_channel_rcu(struct rcu_head *head) +{ + struct ust_app_channel *ua_chan = + caa_container_of(head, struct ust_app_channel, rcu_head); + + ht_cleanup_push(ua_chan->ctx); + ht_cleanup_push(ua_chan->events); + free(ua_chan); +} + /* * Delete ust app channel safely. RCU read lock must be held before calling * this function. @@ -272,6 +367,7 @@ void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan, struct ust_app_event *ua_event; struct ust_app_ctx *ua_ctx; struct ust_app_stream *stream, *stmp; + struct ust_registry_session *registry; assert(ua_chan); @@ -285,11 +381,11 @@ void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan, /* Wipe context */ cds_lfht_for_each_entry(ua_chan->ctx->ht, &iter.iter, ua_ctx, node.node) { + cds_list_del(&ua_ctx->list); ret = lttng_ht_del(ua_chan->ctx, &iter); assert(!ret); delete_ust_app_ctx(sock, ua_ctx); } - lttng_ht_destroy(ua_chan->ctx); /* Wipe events */ cds_lfht_for_each_entry(ua_chan->events->ht, &iter.iter, ua_event, @@ -298,10 +394,14 @@ void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan, assert(!ret); delete_ust_app_event(sock, ua_event); } - lttng_ht_destroy(ua_chan->events); - /* Wipe and free registry. */ - ust_registry_channel_destroy(&ua_chan->session->registry, &ua_chan->registry); + if (ua_chan->session->buffer_type == LTTNG_BUFFER_PER_PID) { + /* Wipe and free registry from session registry. */ + registry = get_session_registry(ua_chan->session); + if (registry) { + ust_registry_channel_del_free(registry, ua_chan->key); + } + } if (ua_chan->obj != NULL) { /* Remove channel from application UST object descriptor. */ @@ -312,41 +412,125 @@ void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan, ERR("UST app sock %d release channel obj failed with ret %d", sock, ret); } - lttng_fd_put(LTTNG_FD_APPS, 2); + lttng_fd_put(LTTNG_FD_APPS, 1); free(ua_chan->obj); } - free(ua_chan); + call_rcu(&ua_chan->rcu_head, delete_ust_app_channel_rcu); } /* - * For a given application and session, push metadata to consumer. The session - * lock MUST be acquired here before calling this. + * Push metadata to consumer socket. * - * Return 0 on success else a negative error. + * The socket lock MUST be acquired. + * The ust app session lock MUST be acquired. + * + * On success, return the len of metadata pushed or else a negative value. */ -static int push_metadata(struct ust_app *app, struct ust_app_session *ua_sess) +ssize_t ust_app_push_metadata(struct ust_registry_session *registry, + struct consumer_socket *socket, int send_zero_data) { int ret; char *metadata_str = NULL; size_t len, offset; - struct consumer_socket *socket; + ssize_t ret_val; - assert(app); - assert(ua_sess); + assert(registry); + assert(socket); - if (!ua_sess->consumer || !ua_sess->metadata) { - /* No consumer means no stream associated so just return gracefully. */ - ret = 0; + /* + * On a push metadata error either the consumer is dead or the metadata + * channel has been destroyed because its endpoint might have died (e.g: + * relayd). If so, the metadata closed flag is set to 1 so we deny pushing + * metadata again which is not valid anymore on the consumer side. + * + * The ust app session mutex locked allows us to make this check without + * the registry lock. + */ + if (registry->metadata_closed) { + return -EPIPE; + } + + pthread_mutex_lock(®istry->lock); + + offset = registry->metadata_len_sent; + len = registry->metadata_len - registry->metadata_len_sent; + if (len == 0) { + DBG3("No metadata to push for metadata key %" PRIu64, + registry->metadata_key); + ret_val = len; + if (send_zero_data) { + DBG("No metadata to push"); + goto push_data; + } goto end; } + /* Allocate only what we have to send. */ + metadata_str = zmalloc(len); + if (!metadata_str) { + PERROR("zmalloc ust app metadata string"); + ret_val = -ENOMEM; + goto error; + } + /* Copy what we haven't send out. */ + memcpy(metadata_str, registry->metadata + offset, len); + registry->metadata_len_sent += len; + +push_data: + pthread_mutex_unlock(®istry->lock); + ret = consumer_push_metadata(socket, registry->metadata_key, + metadata_str, len, offset); + if (ret < 0) { + ret_val = ret; + goto error_push; + } + + free(metadata_str); + return len; + +end: +error: + pthread_mutex_unlock(®istry->lock); +error_push: + free(metadata_str); + return ret_val; +} + +/* + * For a given application and session, push metadata to consumer. The session + * lock MUST be acquired here before calling this. + * Either sock or consumer is required : if sock is NULL, the default + * socket to send the metadata is retrieved from consumer, if sock + * is not NULL we use it to send the metadata. + * + * Return 0 on success else a negative error. + */ +static int push_metadata(struct ust_registry_session *registry, + struct consumer_output *consumer) +{ + int ret_val; + ssize_t ret; + struct consumer_socket *socket; + + assert(registry); + assert(consumer); + rcu_read_lock(); + /* + * Means that no metadata was assigned to the session. This can happens if + * no start has been done previously. + */ + if (!registry->metadata_key) { + ret_val = 0; + goto end_rcu_unlock; + } + /* Get consumer socket to use to push the metadata.*/ - socket = find_consumer_socket_by_bitness(app->bits_per_long, - ua_sess->consumer); + socket = consumer_find_socket_by_bitness(registry->bits_per_long, + consumer); if (!socket) { - ret = -1; + ret_val = -1; goto error_rcu_unlock; } @@ -361,54 +545,26 @@ static int push_metadata(struct ust_app *app, struct ust_app_session *ua_sess) * ability to reorder the metadata it receives. */ pthread_mutex_lock(socket->lock); - pthread_mutex_lock(&ua_sess->registry.lock); - - offset = ua_sess->registry.metadata_len_sent; - len = ua_sess->registry.metadata_len - ua_sess->registry.metadata_len_sent; - if (len == 0) { - DBG3("No metadata to push for session id %d", ua_sess->id); - ret = 0; - goto error_reg_unlock; - } - assert(len > 0); - - /* Allocate only what we have to send. */ - metadata_str = zmalloc(len); - if (!metadata_str) { - PERROR("zmalloc ust app metadata string"); - ret = -ENOMEM; - goto error_reg_unlock; - } - /* Copy what we haven't send out. */ - memcpy(metadata_str, ua_sess->registry.metadata + offset, len); - - pthread_mutex_unlock(&ua_sess->registry.lock); - - ret = ust_consumer_push_metadata(socket, ua_sess, metadata_str, len, - offset); + ret = ust_app_push_metadata(registry, socket, 0); + pthread_mutex_unlock(socket->lock); if (ret < 0) { - pthread_mutex_unlock(socket->lock); + ret_val = ret; goto error_rcu_unlock; } - /* Update len sent of the registry. */ - pthread_mutex_lock(&ua_sess->registry.lock); - ua_sess->registry.metadata_len_sent += len; - pthread_mutex_unlock(&ua_sess->registry.lock); - pthread_mutex_unlock(socket->lock); - rcu_read_unlock(); - free(metadata_str); return 0; -error_reg_unlock: - pthread_mutex_unlock(&ua_sess->registry.lock); - pthread_mutex_unlock(socket->lock); error_rcu_unlock: + /* + * On error, flag the registry that the metadata is closed. We were unable + * to push anything and this means that either the consumer is not + * responding or the metadata cache has been destroyed on the consumer. + */ + registry->metadata_closed = 1; +end_rcu_unlock: rcu_read_unlock(); - free(metadata_str); -end: - return ret; + return ret_val; } /* @@ -419,45 +575,63 @@ end: * * Return 0 on success else a negative value. */ -static int close_metadata(struct ust_app *app, struct ust_app_session *ua_sess) +static int close_metadata(struct ust_registry_session *registry, + struct consumer_output *consumer) { int ret; struct consumer_socket *socket; - assert(app); - assert(ua_sess); + assert(registry); + assert(consumer); - /* Ignore if no metadata. Valid since it can be called on unregister. */ - if (!ua_sess->metadata) { + rcu_read_lock(); + + if (!registry->metadata_key || registry->metadata_closed) { ret = 0; - goto error; + goto end; } - rcu_read_lock(); - /* Get consumer socket to use to push the metadata.*/ - socket = find_consumer_socket_by_bitness(app->bits_per_long, - ua_sess->consumer); + socket = consumer_find_socket_by_bitness(registry->bits_per_long, + consumer); if (!socket) { ret = -1; - goto error_rcu_unlock; + goto error; } - ret = ust_consumer_close_metadata(socket, ua_sess->metadata); + ret = consumer_close_metadata(socket, registry->metadata_key); if (ret < 0) { - goto error_rcu_unlock; + goto error; } -error_rcu_unlock: - /* Destroy metadata on our side since we must not use it anymore. */ - delete_ust_app_channel(-1, ua_sess->metadata, app); - ua_sess->metadata = NULL; - - rcu_read_unlock(); error: + /* + * Metadata closed. Even on error this means that the consumer is not + * responding or not found so either way a second close should NOT be emit + * for this registry. + */ + registry->metadata_closed = 1; +end: + rcu_read_unlock(); return ret; } +/* + * We need to execute ht_destroy outside of RCU read-side critical + * section and outside of call_rcu thread, so we postpone its execution + * using ht_cleanup_push. It is simpler than to change the semantic of + * the many callers of delete_ust_app_session(). + */ +static +void delete_ust_app_session_rcu(struct rcu_head *head) +{ + struct ust_app_session *ua_sess = + caa_container_of(head, struct ust_app_session, rcu_head); + + ht_cleanup_push(ua_sess->channels); + free(ua_sess); +} + /* * Delete ust app session safely. RCU read lock must be held before calling * this function. @@ -469,15 +643,28 @@ void delete_ust_app_session(int sock, struct ust_app_session *ua_sess, int ret; struct lttng_ht_iter iter; struct ust_app_channel *ua_chan; + struct ust_registry_session *registry; assert(ua_sess); - if (ua_sess->metadata) { + pthread_mutex_lock(&ua_sess->lock); + + registry = get_session_registry(ua_sess); + if (registry && !registry->metadata_closed) { /* Push metadata for application before freeing the application. */ - (void) push_metadata(app, ua_sess); + (void) push_metadata(registry, ua_sess->consumer); - /* And ask to close it for this session. */ - (void) close_metadata(app, ua_sess); + /* + * Don't ask to close metadata for global per UID buffers. Close + * metadata only on destroy trace session in this case. Also, the + * previous push metadata could have flag the metadata registry to + * close so don't send a close command if closed. + */ + if (ua_sess->buffer_type != LTTNG_BUFFER_PER_UID && + !registry->metadata_closed) { + /* And ask to close it for this session registry. */ + (void) close_metadata(registry, ua_sess->consumer); + } } cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan, @@ -486,9 +673,15 @@ void delete_ust_app_session(int sock, struct ust_app_session *ua_sess, assert(!ret); delete_ust_app_channel(sock, ua_chan, app); } - lttng_ht_destroy(ua_sess->channels); - ust_registry_session_destroy(&ua_sess->registry); + /* In case of per PID, the registry is kept in the session. */ + if (ua_sess->buffer_type == LTTNG_BUFFER_PER_PID) { + struct buffer_reg_pid *reg_pid = buffer_reg_pid_find(ua_sess->id); + if (reg_pid) { + buffer_reg_pid_remove(reg_pid); + buffer_reg_pid_destroy(reg_pid); + } + } if (ua_sess->handle != -1) { ret = ustctl_release_handle(sock, ua_sess->handle); @@ -497,12 +690,16 @@ void delete_ust_app_session(int sock, struct ust_app_session *ua_sess, sock, ret); } } - free(ua_sess); + pthread_mutex_unlock(&ua_sess->lock); + + call_rcu(&ua_sess->rcu_head, delete_ust_app_session_rcu); } /* * Delete a traceable application structure from the global list. Never call * this function outside of a call_rcu call. + * + * RCU read side lock should _NOT_ be held when calling this function. */ static void delete_ust_app(struct ust_app *app) @@ -510,21 +707,22 @@ void delete_ust_app(struct ust_app *app) int ret, sock; struct ust_app_session *ua_sess, *tmp_ua_sess; - rcu_read_lock(); - /* Delete ust app sessions info */ sock = app->sock; app->sock = -1; - lttng_ht_destroy(app->sessions); - /* Wipe sessions */ cds_list_for_each_entry_safe(ua_sess, tmp_ua_sess, &app->teardown_head, teardown_node) { /* Free every object in the session and the session. */ + rcu_read_lock(); delete_ust_app_session(sock, ua_sess, app); + rcu_read_unlock(); } + ht_cleanup_push(app->sessions); + ht_cleanup_push(app->ust_objd); + /* * Wait until we have deleted the application from the sock hash table * before closing this socket, otherwise an application could re-use the @@ -546,8 +744,6 @@ void delete_ust_app(struct ust_app *app) DBG2("UST app pid %d deleted", app->pid); free(app); - - rcu_read_unlock(); } /* @@ -610,21 +806,9 @@ struct ust_app_session *alloc_ust_app_session(struct ust_app *app) ua_sess->handle = -1; ua_sess->channels = lttng_ht_new(0, LTTNG_HT_TYPE_STRING); pthread_mutex_init(&ua_sess->lock, NULL); - if (ust_registry_session_init(&ua_sess->registry, app, - app->bits_per_long, - app->uint8_t_alignment, - app->uint16_t_alignment, - app->uint32_t_alignment, - app->uint64_t_alignment, - app->long_alignment, - app->byte_order)) { - goto error; - } return ua_sess; -error: - free(ua_sess); error_free: return NULL; } @@ -652,15 +836,14 @@ struct ust_app_channel *alloc_ust_app_channel(char *name, ua_chan->enabled = 1; ua_chan->handle = -1; + ua_chan->session = ua_sess; ua_chan->key = get_next_channel_key(); ua_chan->ctx = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG); ua_chan->events = lttng_ht_new(0, LTTNG_HT_TYPE_STRING); lttng_ht_node_init_str(&ua_chan->node, ua_chan->name); CDS_INIT_LIST_HEAD(&ua_chan->streams.head); - - /* Initialize UST registry. */ - ust_registry_channel_init(&ua_sess->registry, &ua_chan->registry); + CDS_INIT_LIST_HEAD(&ua_chan->ctx_list); /* Copy attributes */ if (attr) { @@ -752,6 +935,8 @@ struct ust_app_ctx *alloc_ust_app_ctx(struct lttng_ust_context *uctx) goto error; } + CDS_INIT_LIST_HEAD(&ua_ctx->list); + if (uctx) { memcpy(&ua_ctx->ctx, uctx, sizeof(ua_ctx->ctx)); } @@ -789,8 +974,7 @@ error: * Find an ust_app using the sock and return it. RCU read side lock must be * held before calling this helper function. */ -static -struct ust_app *find_app_by_sock(int sock) +struct ust_app *ust_app_find_by_sock(int sock) { struct lttng_ht_node_ulong *node; struct lttng_ht_iter iter; @@ -838,7 +1022,8 @@ error: * Return an ust_app_event object or NULL on error. */ static struct ust_app_event *find_ust_app_event(struct lttng_ht *ht, - char *name, struct lttng_ust_filter_bytecode *filter, int loglevel) + char *name, struct lttng_ust_filter_bytecode *filter, int loglevel, + const struct lttng_event_exclusion *exclusion) { struct lttng_ht_iter iter; struct lttng_ht_node_str *node; @@ -852,6 +1037,8 @@ static struct ust_app_event *find_ust_app_event(struct lttng_ht *ht, key.name = name; key.filter = filter; key.loglevel = loglevel; + /* lttng_event_exclusion and lttng_ust_event_exclusion structures are similar */ + key.exclusion = (struct lttng_ust_event_exclusion *)exclusion; /* Lookup using the event name as hash and a custom match fct. */ cds_lfht_lookup(ht->ht, ht->hash_fct((void *) name, lttng_ht_seed), @@ -887,6 +1074,12 @@ int create_ust_channel_context(struct ust_app_channel *ua_chan, ERR("UST app create channel context failed for app (pid: %d) " "with ret %d", app->pid, ret); } else { + /* + * This is normal behavior, an application can die during the + * creation process. Don't report an error so the execution can + * continue normally. + */ + ret = 0; DBG3("UST app disable event failed. Application is dead."); } goto error; @@ -925,6 +1118,12 @@ int set_ust_event_filter(struct ust_app_event *ua_event, ERR("UST app event %s filter failed for app (pid: %d) " "with ret %d", ua_event->attr.name, app->pid, ret); } else { + /* + * This is normal behavior, an application can die during the + * creation process. Don't report an error so the execution can + * continue normally. + */ + ret = 0; DBG3("UST app filter event failed. Application is dead."); } goto error; @@ -937,6 +1136,47 @@ error: return ret; } +/* + * Set event exclusions on the tracer. + */ +static +int set_ust_event_exclusion(struct ust_app_event *ua_event, + struct ust_app *app) +{ + int ret; + + health_code_update(); + + if (!ua_event->exclusion || !ua_event->exclusion->count) { + ret = 0; + goto error; + } + + ret = ustctl_set_exclusion(app->sock, ua_event->exclusion, + ua_event->obj); + if (ret < 0) { + if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) { + ERR("UST app event %s exclusions failed for app (pid: %d) " + "with ret %d", ua_event->attr.name, app->pid, ret); + } else { + /* + * This is normal behavior, an application can die during the + * creation process. Don't report an error so the execution can + * continue normally. + */ + ret = 0; + DBG3("UST app event exclusion failed. Application is dead."); + } + goto error; + } + + DBG2("UST exclusion set successfully for event %s", ua_event->name); + +error: + health_code_update(); + return ret; +} + /* * Disable the specified event on to UST tracer for the UST session. */ @@ -954,6 +1194,12 @@ static int disable_ust_event(struct ust_app *app, "and session handle %d with ret %d", ua_event->attr.name, app->pid, ua_sess->handle, ret); } else { + /* + * This is normal behavior, an application can die during the + * creation process. Don't report an error so the execution can + * continue normally. + */ + ret = 0; DBG3("UST app disable event failed. Application is dead."); } goto error; @@ -984,6 +1230,12 @@ static int disable_ust_channel(struct ust_app *app, "and session handle %d with ret %d", ua_chan->name, app->pid, ua_sess->handle, ret); } else { + /* + * This is normal behavior, an application can die during the + * creation process. Don't report an error so the execution can + * continue normally. + */ + ret = 0; DBG3("UST app disable channel failed. Application is dead."); } goto error; @@ -1014,6 +1266,12 @@ static int enable_ust_channel(struct ust_app *app, "and session handle %d with ret %d", ua_chan->name, app->pid, ua_sess->handle, ret); } else { + /* + * This is normal behavior, an application can die during the + * creation process. Don't report an error so the execution can + * continue normally. + */ + ret = 0; DBG3("UST app enable channel failed. Application is dead."); } goto error; @@ -1046,6 +1304,12 @@ static int enable_ust_event(struct ust_app *app, "and session handle %d with ret %d", ua_event->attr.name, app->pid, ua_sess->handle, ret); } else { + /* + * This is normal behavior, an application can die during the + * creation process. Don't report an error so the execution can + * continue normally. + */ + ret = 0; DBG3("UST app enable event failed. Application is dead."); } goto error; @@ -1060,69 +1324,24 @@ error: } /* - * Create the specified channel onto the UST tracer for a UST session. This - * MUST be called with UST app session lock held. + * Send channel and stream buffer to application. * * Return 0 on success. On error, a negative value is returned. */ -static int create_ust_channel(struct ust_app *app, - struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan, - struct consumer_output *consumer) +static int send_channel_pid_to_ust(struct ust_app *app, + struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan) { int ret; - unsigned int nb_fd = 0; - struct consumer_socket *socket; struct ust_app_stream *stream, *stmp; assert(app); assert(ua_sess); assert(ua_chan); - assert(consumer); - - rcu_read_lock(); - health_code_update(); - - /* Get the right consumer socket for the application. */ - socket = find_consumer_socket_by_bitness(app->bits_per_long, consumer); - if (!socket) { - ret = -1; - goto error; - } - - health_code_update(); - - /* - * Ask consumer to create channel. The consumer will return the number of - * stream we have to expect. - */ - ret = ust_consumer_ask_channel(ua_sess, ua_chan, consumer, socket); - if (ret < 0) { - goto error; - } - - /* - * Compute the number of fd needed before receiving them. It must be 2 per - * stream (2 being the default value here). - */ - nb_fd = DEFAULT_UST_STREAM_FD_NUM * ua_chan->expected_stream_count; - - /* Reserve the amount of file descriptor we need. */ - ret = lttng_fd_get(LTTNG_FD_APPS, nb_fd); - if (ret < 0) { - ERR("Exhausted number of available FD upon create channel"); - goto error_fd_get; - } health_code_update(); - /* - * Now get the channel from the consumer. This call wil populate the stream - * list of that channel and set the ust object. - */ - ret = ust_consumer_get_channel(socket, ua_chan); - if (ret < 0) { - goto error_destroy; - } + DBG("UST app sending channel %s to UST app sock %d", ua_chan->name, + app->sock); /* Send channel to the application. */ ret = ust_consumer_send_channel_to_ust(app, ua_sess, ua_chan); @@ -1142,41 +1361,11 @@ static int create_ust_channel(struct ust_app *app, cds_list_del(&stream->list); delete_ust_app_stream(-1, stream); } - /* Flag the channel that it is sent to the application. */ ua_chan->is_sent = 1; - /* Assign session to channel. */ - ua_chan->session = ua_sess; - /* Initialize ust objd object using the received handle and add it. */ - lttng_ht_node_init_ulong(&ua_chan->ust_objd_node, ua_chan->handle); - lttng_ht_add_unique_ulong(app->ust_objd, &ua_chan->ust_objd_node); - health_code_update(); - - /* If channel is not enabled, disable it on the tracer */ - if (!ua_chan->enabled) { - ret = disable_ust_channel(app, ua_sess, ua_chan); - if (ret < 0) { - goto error; - } - } - - rcu_read_unlock(); - return 0; - -error_destroy: - lttng_fd_put(LTTNG_FD_APPS, nb_fd); -error_fd_get: - /* - * Initiate a destroy channel on the consumer since we had an error - * handling it on our side. The return value is of no importance since we - * already have a ret value set by the previous error that we need to - * return. - */ - (void) ust_consumer_destroy_channel(socket, ua_chan); error: health_code_update(); - rcu_read_unlock(); return ret; } @@ -1201,6 +1390,12 @@ int create_ust_event(struct ust_app *app, struct ust_app_session *ua_sess, ERR("Error ustctl create event %s for app pid: %d with ret %d", ua_event->attr.name, app->pid, ret); } else { + /* + * This is normal behavior, an application can die during the + * creation process. Don't report an error so the execution can + * continue normally. + */ + ret = 0; DBG3("UST app create event failed. Application is dead."); } goto error; @@ -1221,6 +1416,14 @@ int create_ust_event(struct ust_app *app, struct ust_app_session *ua_sess, } } + /* Set exclusions for the event */ + if (ua_event->exclusion) { + ret = set_ust_event_exclusion(ua_event, app); + if (ret < 0) { + goto error; + } + } + /* If event not enabled, disable it on the tracer */ if (ua_event->enabled == 0) { ret = disable_ust_event(app, ua_sess, ua_event); @@ -1256,6 +1459,8 @@ error: static void shadow_copy_event(struct ust_app_event *ua_event, struct ltt_ust_event *uevent) { + size_t exclusion_alloc_size; + strncpy(ua_event->name, uevent->attr.name, sizeof(ua_event->name)); ua_event->name[sizeof(ua_event->name) - 1] = '\0'; @@ -1269,6 +1474,16 @@ static void shadow_copy_event(struct ust_app_event *ua_event, ua_event->filter = alloc_copy_ust_app_filter(uevent->filter); /* Filter might be NULL here in case of ENONEM. */ } + + /* Copy exclusion data */ + if (uevent->exclusion) { + exclusion_alloc_size = sizeof(struct lttng_ust_event_exclusion) + + LTTNG_UST_SYM_NAME_LEN * uevent->exclusion->count; + ua_event->exclusion = zmalloc(exclusion_alloc_size); + if (ua_event->exclusion) { + memcpy(ua_event->exclusion, uevent->exclusion, exclusion_alloc_size); + } + } } /* @@ -1288,6 +1503,9 @@ static void shadow_copy_channel(struct ust_app_channel *ua_chan, strncpy(ua_chan->name, uchan->name, sizeof(ua_chan->name)); ua_chan->name[sizeof(ua_chan->name) - 1] = '\0'; + ua_chan->tracefile_size = uchan->tracefile_size; + ua_chan->tracefile_count = uchan->tracefile_count; + /* Copy event attributes since the layout is different. */ ua_chan->attr.subbuf_size = uchan->attr.subbuf_size; ua_chan->attr.num_subbuf = uchan->attr.num_subbuf; @@ -1301,8 +1519,9 @@ static void shadow_copy_channel(struct ust_app_channel *ua_chan, */ ua_chan->enabled = uchan->enabled; + ua_chan->tracing_channel_id = uchan->id; - cds_lfht_for_each_entry(uchan->ctx->ht, &iter.iter, uctx, node.node) { + cds_list_for_each_entry(uctx, &uchan->ctx_list, list) { ua_ctx = alloc_ust_app_ctx(&uctx->ctx); if (ua_ctx == NULL) { continue; @@ -1310,12 +1529,13 @@ static void shadow_copy_channel(struct ust_app_channel *ua_chan, lttng_ht_node_init_ulong(&ua_ctx->node, (unsigned long) ua_ctx->ctx.ctx); lttng_ht_add_unique_ulong(ua_chan->ctx, &ua_ctx->node); + cds_list_add_tail(&ua_ctx->list, &ua_chan->ctx_list); } /* Copy all events from ltt ust channel to ust app channel */ cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) { ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name, - uevent->filter, uevent->attr.loglevel); + uevent->filter, uevent->attr.loglevel, uevent->exclusion); if (ua_event == NULL) { DBG2("UST event %s not found on shadow copy channel", uevent->attr.name); @@ -1353,20 +1573,39 @@ static void shadow_copy_session(struct ust_app_session *ua_sess, DBG2("Shadow copy of session handle %d", ua_sess->handle); - ua_sess->id = usess->id; - ua_sess->uid = usess->uid; - ua_sess->gid = usess->gid; - - ret = snprintf(ua_sess->path, PATH_MAX, "%s-%d-%s/", app->name, app->pid, - datetime); + ua_sess->tracing_id = usess->id; + ua_sess->id = get_next_session_id(); + ua_sess->uid = app->uid; + ua_sess->gid = app->gid; + ua_sess->euid = usess->uid; + ua_sess->egid = usess->gid; + ua_sess->buffer_type = usess->buffer_type; + ua_sess->bits_per_long = app->bits_per_long; + /* There is only one consumer object per session possible. */ + ua_sess->consumer = usess->consumer; + ua_sess->output_traces = usess->output_traces; + ua_sess->live_timer_interval = usess->live_timer_interval; + + switch (ua_sess->buffer_type) { + case LTTNG_BUFFER_PER_PID: + ret = snprintf(ua_sess->path, sizeof(ua_sess->path), + DEFAULT_UST_TRACE_PID_PATH "/%s-%d-%s", app->name, app->pid, + datetime); + break; + case LTTNG_BUFFER_PER_UID: + ret = snprintf(ua_sess->path, sizeof(ua_sess->path), + DEFAULT_UST_TRACE_UID_PATH, ua_sess->uid, app->bits_per_long); + break; + default: + assert(0); + goto error; + } if (ret < 0) { PERROR("asprintf UST shadow copy session"); - /* TODO: We cannot return an error from here.. */ assert(0); + goto error; } - /* TODO: support all UST domain */ - /* Iterate over all channels in global domain. */ cds_lfht_for_each_entry(usess->domain_global.channels->ht, &iter.iter, uchan, node.node) { @@ -1396,6 +1635,9 @@ static void shadow_copy_session(struct ust_app_session *ua_sess, lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node); } + +error: + return; } /* @@ -1406,7 +1648,7 @@ void __lookup_session_by_app(struct ltt_ust_session *usess, struct ust_app *app, struct lttng_ht_iter *iter) { /* Get right UST app session from app */ - lttng_ht_lookup(app->sessions, (void *)((unsigned long) usess->id), iter); + lttng_ht_lookup(app->sessions, &usess->id, iter); } /* @@ -1417,10 +1659,10 @@ static struct ust_app_session *lookup_session_by_app( struct ltt_ust_session *usess, struct ust_app *app) { struct lttng_ht_iter iter; - struct lttng_ht_node_ulong *node; + struct lttng_ht_node_u64 *node; __lookup_session_by_app(usess, app, &iter); - node = lttng_ht_iter_get_node_ulong(&iter); + node = lttng_ht_iter_get_node_u64(&iter); if (node == NULL) { goto error; } @@ -1431,6 +1673,119 @@ error: return NULL; } +/* + * Setup buffer registry per PID for the given session and application. If none + * is found, a new one is created, added to the global registry and + * initialized. If regp is valid, it's set with the newly created object. + * + * Return 0 on success or else a negative value. + */ +static int setup_buffer_reg_pid(struct ust_app_session *ua_sess, + struct ust_app *app, struct buffer_reg_pid **regp) +{ + int ret = 0; + struct buffer_reg_pid *reg_pid; + + assert(ua_sess); + assert(app); + + rcu_read_lock(); + + reg_pid = buffer_reg_pid_find(ua_sess->id); + if (!reg_pid) { + /* + * This is the create channel path meaning that if there is NO + * registry available, we have to create one for this session. + */ + ret = buffer_reg_pid_create(ua_sess->id, ®_pid); + if (ret < 0) { + goto error; + } + buffer_reg_pid_add(reg_pid); + } else { + goto end; + } + + /* Initialize registry. */ + ret = ust_registry_session_init(®_pid->registry->reg.ust, app, + app->bits_per_long, app->uint8_t_alignment, + app->uint16_t_alignment, app->uint32_t_alignment, + app->uint64_t_alignment, app->long_alignment, + app->byte_order, app->version.major, + app->version.minor); + if (ret < 0) { + goto error; + } + + DBG3("UST app buffer registry per PID created successfully"); + +end: + if (regp) { + *regp = reg_pid; + } +error: + rcu_read_unlock(); + return ret; +} + +/* + * Setup buffer registry per UID for the given session and application. If none + * is found, a new one is created, added to the global registry and + * initialized. If regp is valid, it's set with the newly created object. + * + * Return 0 on success or else a negative value. + */ +static int setup_buffer_reg_uid(struct ltt_ust_session *usess, + struct ust_app *app, struct buffer_reg_uid **regp) +{ + int ret = 0; + struct buffer_reg_uid *reg_uid; + + assert(usess); + assert(app); + + rcu_read_lock(); + + reg_uid = buffer_reg_uid_find(usess->id, app->bits_per_long, app->uid); + if (!reg_uid) { + /* + * This is the create channel path meaning that if there is NO + * registry available, we have to create one for this session. + */ + ret = buffer_reg_uid_create(usess->id, app->bits_per_long, app->uid, + LTTNG_DOMAIN_UST, ®_uid); + if (ret < 0) { + goto error; + } + buffer_reg_uid_add(reg_uid); + } else { + goto end; + } + + /* Initialize registry. */ + ret = ust_registry_session_init(®_uid->registry->reg.ust, NULL, + app->bits_per_long, app->uint8_t_alignment, + app->uint16_t_alignment, app->uint32_t_alignment, + app->uint64_t_alignment, app->long_alignment, + app->byte_order, app->version.major, + app->version.minor); + if (ret < 0) { + goto error; + } + /* Add node to teardown list of the session. */ + cds_list_add(®_uid->lnode, &usess->buffer_reg_uid_list); + + DBG3("UST app buffer registry per UID created successfully"); + +end: + if (regp) { + *regp = reg_uid; + } +error: + rcu_read_unlock(); + return ret; +} + /* * Create a session on the tracer side for the given app. * @@ -1457,7 +1812,7 @@ static int create_ust_app_session(struct ltt_ust_session *usess, ua_sess = lookup_session_by_app(usess, app); if (ua_sess == NULL) { - DBG2("UST app pid: %d session id %d not found, creating it", + DBG2("UST app pid: %d session id %" PRIu64 " not found, creating it", app->pid, usess->id); ua_sess = alloc_ust_app_session(app); if (ua_sess == NULL) { @@ -1469,6 +1824,27 @@ static int create_ust_app_session(struct ltt_ust_session *usess, created = 1; } + switch (usess->buffer_type) { + case LTTNG_BUFFER_PER_PID: + /* Init local registry. */ + ret = setup_buffer_reg_pid(ua_sess, app, NULL); + if (ret < 0) { + goto error; + } + break; + case LTTNG_BUFFER_PER_UID: + /* Look for a global registry. If none exists, create one. */ + ret = setup_buffer_reg_uid(usess, app, NULL); + if (ret < 0) { + goto error; + } + break; + default: + assert(0); + ret = -EINVAL; + goto error; + } + health_code_update(); if (ua_sess->handle == -1) { @@ -1479,6 +1855,13 @@ static int create_ust_app_session(struct ltt_ust_session *usess, app->pid, ret); } else { DBG("UST app creating session failed. Application is dead"); + /* + * This is normal behavior, an application can die during the + * creation process. Don't report an error so the execution can + * continue normally. This will get flagged ENOTCONN and the + * caller will handle it. + */ + ret = 0; } delete_ust_app_session(-1, ua_sess, app); if (ret != -ENOMEM) { @@ -1494,20 +1877,13 @@ static int create_ust_app_session(struct ltt_ust_session *usess, ua_sess->handle = ret; /* Add ust app session to app's HT */ - lttng_ht_node_init_ulong(&ua_sess->node, (unsigned long) ua_sess->id); - lttng_ht_add_unique_ulong(app->sessions, &ua_sess->node); + lttng_ht_node_init_u64(&ua_sess->node, + ua_sess->tracing_id); + lttng_ht_add_unique_u64(app->sessions, &ua_sess->node); DBG2("UST app session created successfully with handle %d", ret); } - /* - * Assign consumer if not already set. For one application, there is only - * one possible consumer has of now. - */ - if (!ua_sess->consumer) { - ua_sess->consumer = usess->consumer; - } - *ua_sess_ptr = ua_sess; if (is_created) { *is_created = created; @@ -1524,7 +1900,7 @@ error: /* * Create a context for the channel on the tracer. * - * Called with UST app session lock held. + * Called with UST app session lock held and a RCU read side lock. */ static int create_ust_app_channel_context(struct ust_app_session *ua_sess, @@ -1554,6 +1930,7 @@ int create_ust_app_channel_context(struct ust_app_session *ua_sess, lttng_ht_node_init_ulong(&ua_ctx->node, (unsigned long) ua_ctx->ctx.ctx); lttng_ht_add_unique_ulong(ua_chan->ctx, &ua_ctx->node); + cds_list_add_tail(&ua_ctx->list, &ua_chan->ctx_list); ret = create_ust_channel_context(ua_chan, ua_ctx, app); if (ret < 0) { @@ -1626,7 +2003,8 @@ error: } /* - * Lookup ust app channel for session and enable it on the tracer side. + * Lookup ust app channel for session and enable it on the tracer side. This + * MUST be called with a RCU read side lock acquired. */ static int enable_ust_app_channel(struct ust_app_session *ua_sess, struct ltt_ust_channel *uchan, struct ust_app *app) @@ -1639,8 +2017,8 @@ static int enable_ust_app_channel(struct ust_app_session *ua_sess, lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter); ua_chan_node = lttng_ht_iter_get_node_str(&iter); if (ua_chan_node == NULL) { - DBG2("Unable to find channel %s in ust session id %u", - uchan->name, ua_sess->id); + DBG2("Unable to find channel %s in ust session id %" PRIu64, + uchan->name, ua_sess->tracing_id); goto error; } @@ -1656,63 +2034,604 @@ error: } /* - * Create UST app channel and create it on the tracer. Set ua_chanp of the - * newly created channel if not NULL. + * Ask the consumer to create a channel and get it if successful. * - * Called with UST app session lock held. + * Return 0 on success or else a negative value. */ -static int create_ust_app_channel(struct ust_app_session *ua_sess, - struct ltt_ust_channel *uchan, struct ust_app *app, - struct consumer_output *consumer, enum lttng_ust_chan_type type, - struct ust_app_channel **ua_chanp) +static int do_consumer_create_channel(struct ltt_ust_session *usess, + struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan, + int bitness, struct ust_registry_session *registry) { - int ret = 0; - struct lttng_ht_iter iter; - struct lttng_ht_node_str *ua_chan_node; - struct ust_app_channel *ua_chan; + int ret; + unsigned int nb_fd = 0; + struct consumer_socket *socket; - /* Lookup channel in the ust app session */ - lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter); - ua_chan_node = lttng_ht_iter_get_node_str(&iter); - if (ua_chan_node != NULL) { - ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node); - goto end; - } + assert(usess); + assert(ua_sess); + assert(ua_chan); + assert(registry); - ua_chan = alloc_ust_app_channel(uchan->name, ua_sess, &uchan->attr); - if (ua_chan == NULL) { - /* Only malloc can fail here */ - ret = -ENOMEM; + rcu_read_lock(); + health_code_update(); + + /* Get the right consumer socket for the application. */ + socket = consumer_find_socket_by_bitness(bitness, usess->consumer); + if (!socket) { + ret = -EINVAL; goto error; } - shadow_copy_channel(ua_chan, uchan); - /* Set channel type. */ - ua_chan->attr.type = type; + health_code_update(); - ret = create_ust_channel(app, ua_sess, ua_chan, consumer); + /* Need one fd for the channel. */ + ret = lttng_fd_get(LTTNG_FD_APPS, 1); if (ret < 0) { + ERR("Exhausted number of available FD upon create channel"); goto error; } - DBG2("UST app create channel %s for PID %d completed", ua_chan->name, - app->pid); + /* + * Ask consumer to create channel. The consumer will return the number of + * stream we have to expect. + */ + ret = ust_consumer_ask_channel(ua_sess, ua_chan, usess->consumer, socket, + registry); + if (ret < 0) { + goto error_ask; + } - /* Only add the channel if successful on the tracer side. */ - lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node); + /* + * Compute the number of fd needed before receiving them. It must be 2 per + * stream (2 being the default value here). + */ + nb_fd = DEFAULT_UST_STREAM_FD_NUM * ua_chan->expected_stream_count; -end: - if (ua_chanp) { - *ua_chanp = ua_chan; + /* Reserve the amount of file descriptor we need. */ + ret = lttng_fd_get(LTTNG_FD_APPS, nb_fd); + if (ret < 0) { + ERR("Exhausted number of available FD upon create channel"); + goto error_fd_get_stream; } - /* Everything went well. */ - return 0; - -error: - delete_ust_app_channel(ua_chan->is_sent ? app->sock : -1, ua_chan, app); - return ret; -} + health_code_update(); + + /* + * Now get the channel from the consumer. This call wil populate the stream + * list of that channel and set the ust objects. + */ + if (usess->consumer->enabled) { + ret = ust_consumer_get_channel(socket, ua_chan); + if (ret < 0) { + goto error_destroy; + } + } + + rcu_read_unlock(); + return 0; + +error_destroy: + lttng_fd_put(LTTNG_FD_APPS, nb_fd); +error_fd_get_stream: + /* + * Initiate a destroy channel on the consumer since we had an error + * handling it on our side. The return value is of no importance since we + * already have a ret value set by the previous error that we need to + * return. + */ + (void) ust_consumer_destroy_channel(socket, ua_chan); +error_ask: + lttng_fd_put(LTTNG_FD_APPS, 1); +error: + health_code_update(); + rcu_read_unlock(); + return ret; +} + +/* + * Duplicate the ust data object of the ust app stream and save it in the + * buffer registry stream. + * + * Return 0 on success or else a negative value. + */ +static int duplicate_stream_object(struct buffer_reg_stream *reg_stream, + struct ust_app_stream *stream) +{ + int ret; + + assert(reg_stream); + assert(stream); + + /* Reserve the amount of file descriptor we need. */ + ret = lttng_fd_get(LTTNG_FD_APPS, 2); + if (ret < 0) { + ERR("Exhausted number of available FD upon duplicate stream"); + goto error; + } + + /* Duplicate object for stream once the original is in the registry. */ + ret = ustctl_duplicate_ust_object_data(&stream->obj, + reg_stream->obj.ust); + if (ret < 0) { + ERR("Duplicate stream obj from %p to %p failed with ret %d", + reg_stream->obj.ust, stream->obj, ret); + lttng_fd_put(LTTNG_FD_APPS, 2); + goto error; + } + stream->handle = stream->obj->handle; + +error: + return ret; +} + +/* + * Duplicate the ust data object of the ust app. channel and save it in the + * buffer registry channel. + * + * Return 0 on success or else a negative value. + */ +static int duplicate_channel_object(struct buffer_reg_channel *reg_chan, + struct ust_app_channel *ua_chan) +{ + int ret; + + assert(reg_chan); + assert(ua_chan); + + /* Need two fds for the channel. */ + ret = lttng_fd_get(LTTNG_FD_APPS, 1); + if (ret < 0) { + ERR("Exhausted number of available FD upon duplicate channel"); + goto error_fd_get; + } + + /* Duplicate object for stream once the original is in the registry. */ + ret = ustctl_duplicate_ust_object_data(&ua_chan->obj, reg_chan->obj.ust); + if (ret < 0) { + ERR("Duplicate channel obj from %p to %p failed with ret: %d", + reg_chan->obj.ust, ua_chan->obj, ret); + goto error; + } + ua_chan->handle = ua_chan->obj->handle; + + return 0; + +error: + lttng_fd_put(LTTNG_FD_APPS, 1); +error_fd_get: + return ret; +} + +/* + * For a given channel buffer registry, setup all streams of the given ust + * application channel. + * + * Return 0 on success or else a negative value. + */ +static int setup_buffer_reg_streams(struct buffer_reg_channel *reg_chan, + struct ust_app_channel *ua_chan) +{ + int ret = 0; + struct ust_app_stream *stream, *stmp; + + assert(reg_chan); + assert(ua_chan); + + DBG2("UST app setup buffer registry stream"); + + /* Send all streams to application. */ + cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) { + struct buffer_reg_stream *reg_stream; + + ret = buffer_reg_stream_create(®_stream); + if (ret < 0) { + goto error; + } + + /* + * Keep original pointer and nullify it in the stream so the delete + * stream call does not release the object. + */ + reg_stream->obj.ust = stream->obj; + stream->obj = NULL; + buffer_reg_stream_add(reg_stream, reg_chan); + + /* We don't need the streams anymore. */ + cds_list_del(&stream->list); + delete_ust_app_stream(-1, stream); + } + +error: + return ret; +} + +/* + * Create a buffer registry channel for the given session registry and + * application channel object. If regp pointer is valid, it's set with the + * created object. Important, the created object is NOT added to the session + * registry hash table. + * + * Return 0 on success else a negative value. + */ +static int create_buffer_reg_channel(struct buffer_reg_session *reg_sess, + struct ust_app_channel *ua_chan, struct buffer_reg_channel **regp) +{ + int ret; + struct buffer_reg_channel *reg_chan = NULL; + + assert(reg_sess); + assert(ua_chan); + + DBG2("UST app creating buffer registry channel for %s", ua_chan->name); + + /* Create buffer registry channel. */ + ret = buffer_reg_channel_create(ua_chan->tracing_channel_id, ®_chan); + if (ret < 0) { + goto error_create; + } + assert(reg_chan); + reg_chan->consumer_key = ua_chan->key; + reg_chan->subbuf_size = ua_chan->attr.subbuf_size; + + /* Create and add a channel registry to session. */ + ret = ust_registry_channel_add(reg_sess->reg.ust, + ua_chan->tracing_channel_id); + if (ret < 0) { + goto error; + } + buffer_reg_channel_add(reg_sess, reg_chan); + + if (regp) { + *regp = reg_chan; + } + + return 0; + +error: + /* Safe because the registry channel object was not added to any HT. */ + buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST); +error_create: + return ret; +} + +/* + * Setup buffer registry channel for the given session registry and application + * channel object. If regp pointer is valid, it's set with the created object. + * + * Return 0 on success else a negative value. + */ +static int setup_buffer_reg_channel(struct buffer_reg_session *reg_sess, + struct ust_app_channel *ua_chan, struct buffer_reg_channel *reg_chan) +{ + int ret; + + assert(reg_sess); + assert(reg_chan); + assert(ua_chan); + assert(ua_chan->obj); + + DBG2("UST app setup buffer registry channel for %s", ua_chan->name); + + /* Setup all streams for the registry. */ + ret = setup_buffer_reg_streams(reg_chan, ua_chan); + if (ret < 0) { + goto error; + } + + reg_chan->obj.ust = ua_chan->obj; + ua_chan->obj = NULL; + + return 0; + +error: + buffer_reg_channel_remove(reg_sess, reg_chan); + buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST); + return ret; +} + +/* + * Send buffer registry channel to the application. + * + * Return 0 on success else a negative value. + */ +static int send_channel_uid_to_ust(struct buffer_reg_channel *reg_chan, + struct ust_app *app, struct ust_app_session *ua_sess, + struct ust_app_channel *ua_chan) +{ + int ret; + struct buffer_reg_stream *reg_stream; + + assert(reg_chan); + assert(app); + assert(ua_sess); + assert(ua_chan); + + DBG("UST app sending buffer registry channel to ust sock %d", app->sock); + + ret = duplicate_channel_object(reg_chan, ua_chan); + if (ret < 0) { + goto error; + } + + /* Send channel to the application. */ + ret = ust_consumer_send_channel_to_ust(app, ua_sess, ua_chan); + if (ret < 0) { + goto error; + } + + health_code_update(); + + /* Send all streams to application. */ + pthread_mutex_lock(®_chan->stream_list_lock); + cds_list_for_each_entry(reg_stream, ®_chan->streams, lnode) { + struct ust_app_stream stream; + + ret = duplicate_stream_object(reg_stream, &stream); + if (ret < 0) { + goto error_stream_unlock; + } + + ret = ust_consumer_send_stream_to_ust(app, ua_chan, &stream); + if (ret < 0) { + (void) release_ust_app_stream(-1, &stream); + goto error_stream_unlock; + } + + /* + * The return value is not important here. This function will output an + * error if needed. + */ + (void) release_ust_app_stream(-1, &stream); + } + ua_chan->is_sent = 1; + +error_stream_unlock: + pthread_mutex_unlock(®_chan->stream_list_lock); +error: + return ret; +} + +/* + * Create and send to the application the created buffers with per UID buffers. + * + * Return 0 on success else a negative value. + */ +static int create_channel_per_uid(struct ust_app *app, + struct ltt_ust_session *usess, struct ust_app_session *ua_sess, + struct ust_app_channel *ua_chan) +{ + int ret; + struct buffer_reg_uid *reg_uid; + struct buffer_reg_channel *reg_chan; + + assert(app); + assert(usess); + assert(ua_sess); + assert(ua_chan); + + DBG("UST app creating channel %s with per UID buffers", ua_chan->name); + + reg_uid = buffer_reg_uid_find(usess->id, app->bits_per_long, app->uid); + /* + * The session creation handles the creation of this global registry + * object. If none can be find, there is a code flow problem or a + * teardown race. + */ + assert(reg_uid); + + reg_chan = buffer_reg_channel_find(ua_chan->tracing_channel_id, + reg_uid); + if (!reg_chan) { + /* Create the buffer registry channel object. */ + ret = create_buffer_reg_channel(reg_uid->registry, ua_chan, ®_chan); + if (ret < 0) { + goto error; + } + assert(reg_chan); + + /* + * Create the buffers on the consumer side. This call populates the + * ust app channel object with all streams and data object. + */ + ret = do_consumer_create_channel(usess, ua_sess, ua_chan, + app->bits_per_long, reg_uid->registry->reg.ust); + if (ret < 0) { + /* + * Let's remove the previously created buffer registry channel so + * it's not visible anymore in the session registry. + */ + ust_registry_channel_del_free(reg_uid->registry->reg.ust, + ua_chan->tracing_channel_id); + buffer_reg_channel_remove(reg_uid->registry, reg_chan); + buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST); + goto error; + } + + /* + * Setup the streams and add it to the session registry. + */ + ret = setup_buffer_reg_channel(reg_uid->registry, ua_chan, reg_chan); + if (ret < 0) { + goto error; + } + + } + + /* Send buffers to the application. */ + ret = send_channel_uid_to_ust(reg_chan, app, ua_sess, ua_chan); + if (ret < 0) { + goto error; + } + +error: + return ret; +} + +/* + * Create and send to the application the created buffers with per PID buffers. + * + * Return 0 on success else a negative value. + */ +static int create_channel_per_pid(struct ust_app *app, + struct ltt_ust_session *usess, struct ust_app_session *ua_sess, + struct ust_app_channel *ua_chan) +{ + int ret; + struct ust_registry_session *registry; + + assert(app); + assert(usess); + assert(ua_sess); + assert(ua_chan); + + DBG("UST app creating channel %s with per PID buffers", ua_chan->name); + + rcu_read_lock(); + + registry = get_session_registry(ua_sess); + assert(registry); + + /* Create and add a new channel registry to session. */ + ret = ust_registry_channel_add(registry, ua_chan->key); + if (ret < 0) { + goto error; + } + + /* Create and get channel on the consumer side. */ + ret = do_consumer_create_channel(usess, ua_sess, ua_chan, + app->bits_per_long, registry); + if (ret < 0) { + goto error; + } + + ret = send_channel_pid_to_ust(app, ua_sess, ua_chan); + if (ret < 0) { + goto error; + } + +error: + rcu_read_unlock(); + return ret; +} + +/* + * From an already allocated ust app channel, create the channel buffers if + * need and send it to the application. This MUST be called with a RCU read + * side lock acquired. + * + * Return 0 on success or else a negative value. + */ +static int do_create_channel(struct ust_app *app, + struct ltt_ust_session *usess, struct ust_app_session *ua_sess, + struct ust_app_channel *ua_chan) +{ + int ret; + + assert(app); + assert(usess); + assert(ua_sess); + assert(ua_chan); + + /* Handle buffer type before sending the channel to the application. */ + switch (usess->buffer_type) { + case LTTNG_BUFFER_PER_UID: + { + ret = create_channel_per_uid(app, usess, ua_sess, ua_chan); + if (ret < 0) { + goto error; + } + break; + } + case LTTNG_BUFFER_PER_PID: + { + ret = create_channel_per_pid(app, usess, ua_sess, ua_chan); + if (ret < 0) { + goto error; + } + break; + } + default: + assert(0); + ret = -EINVAL; + goto error; + } + + /* Initialize ust objd object using the received handle and add it. */ + lttng_ht_node_init_ulong(&ua_chan->ust_objd_node, ua_chan->handle); + lttng_ht_add_unique_ulong(app->ust_objd, &ua_chan->ust_objd_node); + + /* If channel is not enabled, disable it on the tracer */ + if (!ua_chan->enabled) { + ret = disable_ust_channel(app, ua_sess, ua_chan); + if (ret < 0) { + goto error; + } + } + +error: + return ret; +} + +/* + * Create UST app channel and create it on the tracer. Set ua_chanp of the + * newly created channel if not NULL. + * + * Called with UST app session lock and RCU read-side lock held. + * + * Return 0 on success or else a negative value. + */ +static int create_ust_app_channel(struct ust_app_session *ua_sess, + struct ltt_ust_channel *uchan, struct ust_app *app, + enum lttng_ust_chan_type type, struct ltt_ust_session *usess, + struct ust_app_channel **ua_chanp) +{ + int ret = 0; + struct lttng_ht_iter iter; + struct lttng_ht_node_str *ua_chan_node; + struct ust_app_channel *ua_chan; + + /* Lookup channel in the ust app session */ + lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter); + ua_chan_node = lttng_ht_iter_get_node_str(&iter); + if (ua_chan_node != NULL) { + ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node); + goto end; + } + + ua_chan = alloc_ust_app_channel(uchan->name, ua_sess, &uchan->attr); + if (ua_chan == NULL) { + /* Only malloc can fail here */ + ret = -ENOMEM; + goto error_alloc; + } + shadow_copy_channel(ua_chan, uchan); + + /* Set channel type. */ + ua_chan->attr.type = type; + + ret = do_create_channel(app, usess, ua_sess, ua_chan); + if (ret < 0) { + goto error; + } + + DBG2("UST app create channel %s for PID %d completed", ua_chan->name, + app->pid); + + /* Only add the channel if successful on the tracer side. */ + lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node); + +end: + if (ua_chanp) { + *ua_chanp = ua_chan; + } + + /* Everything went well. */ + return 0; + +error: + delete_ust_app_channel(ua_chan->is_sent ? app->sock : -1, ua_chan, app); +error_alloc: + return ret; +} /* * Create UST app event and create it on the tracer side. @@ -1729,7 +2648,7 @@ int create_ust_app_event(struct ust_app_session *ua_sess, /* Get event node */ ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name, - uevent->filter, uevent->attr.loglevel); + uevent->filter, uevent->attr.loglevel, uevent->exclusion); if (ua_event != NULL) { ret = -EEXIST; goto end; @@ -1769,22 +2688,28 @@ error: /* * Create UST metadata and open it on the tracer side. * - * Called with UST app session lock held. + * Called with UST app session lock held and RCU read side lock. */ static int create_ust_app_metadata(struct ust_app_session *ua_sess, - struct ust_app *app, struct consumer_output *consumer) + struct ust_app *app, struct consumer_output *consumer, + struct ustctl_consumer_channel_attr *attr) { int ret = 0; struct ust_app_channel *metadata; struct consumer_socket *socket; + struct ust_registry_session *registry; assert(ua_sess); assert(app); assert(consumer); - if (ua_sess->metadata) { - /* Already exist. Return success. */ - goto end; + registry = get_session_registry(ua_sess); + assert(registry); + + /* Metadata already exists for this registry or it was closed previously */ + if (registry->metadata_key || registry->metadata_closed) { + ret = 0; + goto error; } /* Allocate UST metadata */ @@ -1795,30 +2720,54 @@ static int create_ust_app_metadata(struct ust_app_session *ua_sess, goto error; } - /* Set default attributes for metadata. */ - metadata->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE; - metadata->attr.subbuf_size = default_get_metadata_subbuf_size(); - metadata->attr.num_subbuf = DEFAULT_METADATA_SUBBUF_NUM; - metadata->attr.switch_timer_interval = DEFAULT_UST_CHANNEL_SWITCH_TIMER; - metadata->attr.read_timer_interval = DEFAULT_UST_CHANNEL_READ_TIMER; - metadata->attr.output = LTTNG_UST_MMAP; - metadata->attr.type = LTTNG_UST_CHAN_METADATA; + if (!attr) { + /* Set default attributes for metadata. */ + metadata->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE; + metadata->attr.subbuf_size = default_get_metadata_subbuf_size(); + metadata->attr.num_subbuf = DEFAULT_METADATA_SUBBUF_NUM; + metadata->attr.switch_timer_interval = DEFAULT_METADATA_SWITCH_TIMER; + metadata->attr.read_timer_interval = DEFAULT_METADATA_READ_TIMER; + metadata->attr.output = LTTNG_UST_MMAP; + metadata->attr.type = LTTNG_UST_CHAN_METADATA; + } else { + memcpy(&metadata->attr, attr, sizeof(metadata->attr)); + metadata->attr.output = LTTNG_UST_MMAP; + metadata->attr.type = LTTNG_UST_CHAN_METADATA; + } + + /* Need one fd for the channel. */ + ret = lttng_fd_get(LTTNG_FD_APPS, 1); + if (ret < 0) { + ERR("Exhausted number of available FD upon create metadata"); + goto error; + } /* Get the right consumer socket for the application. */ - socket = find_consumer_socket_by_bitness(app->bits_per_long, consumer); + socket = consumer_find_socket_by_bitness(app->bits_per_long, consumer); if (!socket) { ret = -EINVAL; goto error_consumer; } + /* + * Keep metadata key so we can identify it on the consumer side. Assign it + * to the registry *before* we ask the consumer so we avoid the race of the + * consumer requesting the metadata and the ask_channel call on our side + * did not returned yet. + */ + registry->metadata_key = metadata->key; + /* * Ask the metadata channel creation to the consumer. The metadata object * will be created by the consumer and kept their. However, the stream is * never added or monitored until we do a first push metadata to the * consumer. */ - ret = ust_consumer_ask_channel(ua_sess, metadata, consumer, socket); + ret = ust_consumer_ask_channel(ua_sess, metadata, consumer, socket, + registry); if (ret < 0) { + /* Nullify the metadata key so we don't try to close it later on. */ + registry->metadata_key = 0; goto error_consumer; } @@ -1828,18 +2777,18 @@ static int create_ust_app_metadata(struct ust_app_session *ua_sess, * because after this point, if an error occurs, the only way the stream * can be deleted is to be monitored in the consumer. */ - ret = ust_consumer_setup_metadata(socket, metadata); + ret = consumer_setup_metadata(socket, metadata->key); if (ret < 0) { + /* Nullify the metadata key so we don't try to close it later on. */ + registry->metadata_key = 0; goto error_consumer; } - ua_sess->metadata = metadata; - - DBG2("UST metadata created for app pid %d", app->pid); + DBG2("UST metadata with key %" PRIu64 " created for app pid %d", + metadata->key, app->pid); -end: - return 0; error_consumer: + lttng_fd_put(LTTNG_FD_APPS, 1); delete_ust_app_channel(-1, metadata, app); error: return ret; @@ -1924,7 +2873,7 @@ struct ust_app *ust_app_create(struct ust_register_msg *msg, int sock) lta->v_major = msg->major; lta->v_minor = msg->minor; - lta->sessions = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG); + lta->sessions = lttng_ht_new(0, LTTNG_HT_TYPE_U64); lta->ust_objd = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG); lta->notify_sock = -1; @@ -2061,6 +3010,8 @@ void ust_app_unregister(int sock) /* Remove sessions so they are not visible during deletion.*/ cds_lfht_for_each_entry(lta->sessions->ht, &iter.iter, ua_sess, node.node) { + struct ust_registry_session *registry; + ret = lttng_ht_del(lta->sessions, &iter); if (ret) { /* The session was already removed so scheduled for teardown. */ @@ -2084,8 +3035,23 @@ void ust_app_unregister(int sock) * The close metadata below nullifies the metadata pointer in the * session so the delete session will NOT push/close a second time. */ - (void) push_metadata(lta, ua_sess); - (void) close_metadata(lta, ua_sess); + registry = get_session_registry(ua_sess); + if (registry && !registry->metadata_closed) { + /* Push metadata for application before freeing the application. */ + (void) push_metadata(registry, ua_sess->consumer); + + /* + * Don't ask to close metadata for global per UID buffers. Close + * metadata only on destroy trace session in this case. Also, the + * previous push metadata could have flag the metadata registry to + * close so don't send a close command if closed. + */ + if (ua_sess->buffer_type != LTTNG_BUFFER_PER_UID && + !registry->metadata_closed) { + /* And ask to close it for this session registry. */ + (void) close_metadata(registry, ua_sess->consumer); + } + } cds_list_add(&ua_sess->teardown_node, <a->teardown_head); pthread_mutex_unlock(&ua_sess->lock); @@ -2164,6 +3130,12 @@ int ust_app_list_events(struct lttng_event **events) app->sock, ret); } else { DBG3("UST app tp list get failed. Application is dead"); + /* + * This is normal behavior, an application can die during the + * creation process. Don't report an error so the execution can + * continue normally. Continue normal execution. + */ + break; } goto rcu_error; } @@ -2258,6 +3230,12 @@ int ust_app_list_event_fields(struct lttng_event_field **fields) app->sock, ret); } else { DBG3("UST app tp list field failed. Application is dead"); + /* + * This is normal behavior, an application can die during the + * creation process. Don't report an error so the execution can + * continue normally. + */ + break; } goto rcu_error; } @@ -2307,6 +3285,8 @@ error: /* * Free and clean all traceable apps of the global list. + * + * Should _NOT_ be called with RCU read-side lock held. */ void ust_app_clean_list(void) { @@ -2337,13 +3317,12 @@ void ust_app_clean_list(void) ret = lttng_ht_del(ust_app_ht_by_notify_sock, &iter); assert(!ret); } + rcu_read_unlock(); /* Destroy is done only when the ht is empty */ - lttng_ht_destroy(ust_app_ht); - lttng_ht_destroy(ust_app_ht_by_sock); - lttng_ht_destroy(ust_app_ht_by_notify_sock); - - rcu_read_unlock(); + ht_cleanup_push(ust_app_ht); + ht_cleanup_push(ust_app_ht_by_sock); + ht_cleanup_push(ust_app_ht_by_notify_sock); } /* @@ -2375,7 +3354,7 @@ int ust_app_disable_channel_glb(struct ltt_ust_session *usess, goto error; } - DBG2("UST app disabling channel %s from global domain for session id %d", + DBG2("UST app disabling channel %s from global domain for session id %" PRIu64, uchan->name, usess->id); rcu_read_lock(); @@ -2436,7 +3415,7 @@ int ust_app_enable_channel_glb(struct ltt_ust_session *usess, goto error; } - DBG2("UST app enabling channel %s to global domain for session id %d", + DBG2("UST app enabling channel %s to global domain for session id %" PRIu64, uchan->name, usess->id); rcu_read_lock(); @@ -2484,7 +3463,8 @@ int ust_app_disable_event_glb(struct ltt_ust_session *usess, struct ust_app_event *ua_event; DBG("UST app disabling event %s for all apps in channel " - "%s for session id %d", uevent->attr.name, uchan->name, usess->id); + "%s for session id %" PRIu64, + uevent->attr.name, uchan->name, usess->id); rcu_read_lock(); @@ -2507,7 +3487,7 @@ int ust_app_disable_event_glb(struct ltt_ust_session *usess, lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter); ua_chan_node = lttng_ht_iter_get_node_str(&uiter); if (ua_chan_node == NULL) { - DBG2("Channel %s not found in session id %d for app pid %d." + DBG2("Channel %s not found in session id %" PRIu64 " for app pid %d." "Skipping", uchan->name, usess->id, app->pid); continue; } @@ -2550,7 +3530,7 @@ int ust_app_disable_all_event_glb(struct ltt_ust_session *usess, struct ust_app_event *ua_event; DBG("UST app disabling all event for all apps in channel " - "%s for session id %d", uchan->name, usess->id); + "%s for session id %" PRIu64, uchan->name, usess->id); rcu_read_lock(); @@ -2608,7 +3588,7 @@ int ust_app_create_channel_glb(struct ltt_ust_session *usess, assert(usess); assert(uchan); - DBG2("UST app adding channel %s to global domain for session id %d", + DBG2("UST app adding channel %s to UST domain for session id %" PRIu64, uchan->name, usess->id); rcu_read_lock(); @@ -2645,9 +3625,17 @@ int ust_app_create_channel_glb(struct ltt_ust_session *usess, assert(ua_sess); pthread_mutex_lock(&ua_sess->lock); - /* Create channel onto application. We don't need the chan ref. */ - ret = create_ust_app_channel(ua_sess, uchan, app, usess->consumer, - LTTNG_UST_CHAN_PER_CPU, NULL); + if (!strncmp(uchan->name, DEFAULT_METADATA_NAME, + sizeof(uchan->name))) { + struct ustctl_consumer_channel_attr attr; + copy_channel_attr_to_ustctl(&attr, &uchan->attr); + ret = create_ust_app_metadata(ua_sess, app, usess->consumer, + &attr); + } else { + /* Create channel onto application. We don't need the chan ref. */ + ret = create_ust_app_channel(ua_sess, uchan, app, + LTTNG_UST_CHAN_PER_CPU, usess, NULL); + } pthread_mutex_unlock(&ua_sess->lock); if (ret < 0) { if (ret == -ENOMEM) { @@ -2680,7 +3668,7 @@ int ust_app_enable_event_glb(struct ltt_ust_session *usess, struct ust_app_channel *ua_chan; struct ust_app_event *ua_event; - DBG("UST app enabling event %s for all apps for session id %d", + DBG("UST app enabling event %s for all apps for session id %" PRIu64, uevent->attr.name, usess->id); /* @@ -2718,7 +3706,7 @@ int ust_app_enable_event_glb(struct ltt_ust_session *usess, /* Get event node */ ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name, - uevent->filter, uevent->attr.loglevel); + uevent->filter, uevent->attr.loglevel, uevent->exclusion); if (ua_event == NULL) { DBG3("UST app enable event %s not found for app PID %d." "Skipping app", uevent->attr.name, app->pid); @@ -2753,7 +3741,7 @@ int ust_app_create_event_glb(struct ltt_ust_session *usess, struct ust_app_session *ua_sess; struct ust_app_channel *ua_chan; - DBG("UST app creating event %s for all apps for session id %d", + DBG("UST app creating event %s for all apps for session id %" PRIu64, uevent->attr.name, usess->id); rcu_read_lock(); @@ -2803,6 +3791,7 @@ int ust_app_create_event_glb(struct ltt_ust_session *usess, /* * Start tracing for a specific UST session and app. */ +static int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app) { int ret = 0; @@ -2833,7 +3822,7 @@ int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app) if (usess->consumer->type == CONSUMER_DST_LOCAL && strlen(usess->consumer->dst.trace_path) > 0) { ret = run_as_mkdir_recursive(usess->consumer->dst.trace_path, - S_IRWXU | S_IRWXG, usess->uid, usess->gid); + S_IRWXU | S_IRWXG, ua_sess->euid, ua_sess->egid); if (ret < 0) { if (ret != -EEXIST) { ERR("Trace directory creation error"); @@ -2842,8 +3831,11 @@ int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app) } } - /* Create the metadata for the application. */ - ret = create_ust_app_metadata(ua_sess, app, usess->consumer); + /* + * Create the metadata for the application. This returns gracefully if a + * metadata was already set for the session. + */ + ret = create_ust_app_metadata(ua_sess, app, usess->consumer, NULL); if (ret < 0) { goto error_unlock; } @@ -2859,6 +3851,13 @@ skip_setup: app->pid, ret); } else { DBG("UST app start session failed. Application is dead."); + /* + * This is normal behavior, an application can die during the + * creation process. Don't report an error so the execution can + * continue normally. + */ + pthread_mutex_unlock(&ua_sess->lock); + goto end; } goto error_unlock; } @@ -2892,12 +3891,12 @@ error_unlock: /* * Stop tracing for a specific UST session and app. */ +static int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app) { int ret = 0; - struct lttng_ht_iter iter; struct ust_app_session *ua_sess; - struct ust_app_channel *ua_chan; + struct ust_registry_session *registry; DBG("Stopping tracing for ust app pid %d", app->pid); @@ -2934,6 +3933,12 @@ int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app) app->pid, ret); } else { DBG("UST app stop session failed. Application is dead."); + /* + * This is normal behavior, an application can die during the + * creation process. Don't report an error so the execution can + * continue normally. + */ + goto end_unlock; } goto error_rcu_unlock; } @@ -2949,6 +3954,56 @@ int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app) health_code_update(); + registry = get_session_registry(ua_sess); + assert(registry); + + if (!registry->metadata_closed) { + /* Push metadata for application before freeing the application. */ + (void) push_metadata(registry, ua_sess->consumer); + } + +end_unlock: + pthread_mutex_unlock(&ua_sess->lock); +end_no_session: + rcu_read_unlock(); + health_code_update(); + return 0; + +error_rcu_unlock: + pthread_mutex_unlock(&ua_sess->lock); + rcu_read_unlock(); + health_code_update(); + return -1; +} + +/* + * Flush buffers for a specific UST session and app. + */ +static +int ust_app_flush_trace(struct ltt_ust_session *usess, struct ust_app *app) +{ + int ret = 0; + struct lttng_ht_iter iter; + struct ust_app_session *ua_sess; + struct ust_app_channel *ua_chan; + + DBG("Flushing buffers for ust app pid %d", app->pid); + + rcu_read_lock(); + + if (!app->compatible) { + goto end_no_session; + } + + ua_sess = lookup_session_by_app(usess, app); + if (ua_sess == NULL) { + goto end_no_session; + } + + pthread_mutex_lock(&ua_sess->lock); + + health_code_update(); + /* Flushing buffers */ cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan, node.node) { @@ -2962,8 +4017,11 @@ int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app) } else { DBG3("UST app failed to flush %s. Application is dead.", ua_chan->name); - /* No need to continue. */ - break; + /* + * This is normal behavior, an application can die during the + * creation process. Don't report an error so the execution can + * continue normally. + */ } /* Continuing flushing all buffers */ continue; @@ -2972,22 +4030,11 @@ int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app) health_code_update(); - ret = push_metadata(app, ua_sess); - if (ret < 0) { - goto error_rcu_unlock; - } - pthread_mutex_unlock(&ua_sess->lock); end_no_session: rcu_read_unlock(); health_code_update(); return 0; - -error_rcu_unlock: - pthread_mutex_unlock(&ua_sess->lock); - rcu_read_unlock(); - health_code_update(); - return -1; } /* @@ -2998,7 +4045,7 @@ static int destroy_trace(struct ltt_ust_session *usess, struct ust_app *app) int ret; struct ust_app_session *ua_sess; struct lttng_ht_iter iter; - struct lttng_ht_node_ulong *node; + struct lttng_ht_node_u64 *node; DBG("Destroy tracing for ust app pid %d", app->pid); @@ -3009,7 +4056,7 @@ static int destroy_trace(struct ltt_ust_session *usess, struct ust_app *app) } __lookup_session_by_app(usess, app, &iter); - node = lttng_ht_iter_get_node_ulong(&iter); + node = lttng_ht_iter_get_node_u64(&iter); if (node == NULL) { /* Session is being or is deleted. */ goto end; @@ -3075,12 +4122,64 @@ int ust_app_stop_trace_all(struct ltt_ust_session *usess) cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) { ret = ust_app_stop_trace(usess, app); if (ret < 0) { - ERR("UST app stop trace failed with ret %d", ret); /* Continue to next apps even on error */ continue; } } + /* Flush buffers and push metadata (for UID buffers). */ + switch (usess->buffer_type) { + case LTTNG_BUFFER_PER_UID: + { + struct buffer_reg_uid *reg; + + /* Flush all per UID buffers associated to that session. */ + cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) { + struct ust_registry_session *ust_session_reg; + struct buffer_reg_channel *reg_chan; + struct consumer_socket *socket; + + /* Get consumer socket to use to push the metadata.*/ + socket = consumer_find_socket_by_bitness(reg->bits_per_long, + usess->consumer); + if (!socket) { + /* Ignore request if no consumer is found for the session. */ + continue; + } + + cds_lfht_for_each_entry(reg->registry->channels->ht, &iter.iter, + reg_chan, node.node) { + /* + * The following call will print error values so the return + * code is of little importance because whatever happens, we + * have to try them all. + */ + (void) consumer_flush_channel(socket, reg_chan->consumer_key); + } + + ust_session_reg = reg->registry->reg.ust; + if (!ust_session_reg->metadata_closed) { + /* Push metadata. */ + (void) push_metadata(ust_session_reg, usess->consumer); + } + } + + break; + } + case LTTNG_BUFFER_PER_PID: + cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) { + ret = ust_app_flush_trace(usess, app); + if (ret < 0) { + /* Continue to next apps even on error */ + continue; + } + } + break; + default: + assert(0); + break; + } + rcu_read_unlock(); return 0; @@ -3118,7 +4217,7 @@ int ust_app_destroy_trace_all(struct ltt_ust_session *usess) void ust_app_global_update(struct ltt_ust_session *usess, int sock) { int ret = 0; - struct lttng_ht_iter iter, uiter, iter_ctx; + struct lttng_ht_iter iter, uiter; struct ust_app *app; struct ust_app_session *ua_sess = NULL; struct ust_app_channel *ua_chan; @@ -3128,12 +4227,12 @@ void ust_app_global_update(struct ltt_ust_session *usess, int sock) assert(usess); assert(sock >= 0); - DBG2("UST app global update for app sock %d for session id %d", sock, + DBG2("UST app global update for app sock %d for session id %" PRIu64, sock, usess->id); rcu_read_lock(); - app = find_app_by_sock(sock); + app = ust_app_find_by_sock(sock); if (app == NULL) { /* * Application can be unregistered before so this is possible hence @@ -3163,18 +4262,38 @@ void ust_app_global_update(struct ltt_ust_session *usess, int sock) */ cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan, node.node) { - ret = create_ust_channel(app, ua_sess, ua_chan, usess->consumer); - if (ret < 0) { - /* - * Stop everything. On error, the application failed, no more file - * descriptor are available or ENOMEM so stopping here is the only - * thing we can do for now. - */ - goto error_unlock; + /* + * For a metadata channel, handle it differently. + */ + if (!strncmp(ua_chan->name, DEFAULT_METADATA_NAME, + sizeof(ua_chan->name))) { + ret = create_ust_app_metadata(ua_sess, app, usess->consumer, + &ua_chan->attr); + if (ret < 0) { + goto error_unlock; + } + /* Remove it from the hash table and continue!. */ + ret = lttng_ht_del(ua_sess->channels, &iter); + assert(!ret); + delete_ust_app_channel(-1, ua_chan, app); + continue; + } else { + ret = do_create_channel(app, usess, ua_sess, ua_chan); + if (ret < 0) { + /* + * Stop everything. On error, the application failed, no more + * file descriptor are available or ENOMEM so stopping here is + * the only thing we can do for now. + */ + goto error_unlock; + } } - cds_lfht_for_each_entry(ua_chan->ctx->ht, &iter_ctx.iter, ua_ctx, - node.node) { + /* + * Add context using the list so they are enabled in the same order the + * user added them. + */ + cds_list_for_each_entry(ua_ctx, &ua_chan->ctx_list, list) { ret = create_ust_channel_context(ua_chan, ua_ctx, app); if (ret < 0) { goto error_unlock; @@ -3313,7 +4432,7 @@ int ust_app_enable_event_pid(struct ltt_ust_session *usess, ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node); ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name, - uevent->filter, uevent->attr.loglevel); + uevent->filter, uevent->attr.loglevel, uevent->exclusion); if (ua_event == NULL) { ret = create_ust_app_event(ua_sess, ua_chan, uevent, app); if (ret < 0) { @@ -3531,10 +4650,13 @@ static int reply_ust_register_channel(int sock, int sobjd, int cobjd, { int ret, ret_code = 0; uint32_t chan_id, reg_count; + uint64_t chan_reg_key; enum ustctl_channel_header type; struct ust_app *app; struct ust_app_channel *ua_chan; struct ust_app_session *ua_sess; + struct ust_registry_session *registry; + struct ust_registry_channel *chan_reg; rcu_read_lock(); @@ -3544,48 +4666,62 @@ static int reply_ust_register_channel(int sock, int sobjd, int cobjd, DBG("Application socket %d is being teardown. Abort event notify", sock); ret = 0; + free(fields); goto error_rcu_unlock; } - /* Lookup channel by UST object descriptor. Should always be found. */ + /* Lookup channel by UST object descriptor. */ ua_chan = find_channel_by_objd(app, cobjd); - assert(ua_chan); + if (!ua_chan) { + DBG("Application channel is being teardown. Abort event notify"); + ret = 0; + free(fields); + goto error_rcu_unlock; + } + assert(ua_chan->session); ua_sess = ua_chan->session; - assert(ua_sess); - pthread_mutex_lock(&ua_sess->registry.lock); - - if (ust_registry_is_max_id(ua_chan->session->registry.used_channel_id)) { - ret_code = -1; - chan_id = -1U; - type = -1; - goto reply; - } + /* Get right session registry depending on the session buffer type. */ + registry = get_session_registry(ua_sess); + assert(registry); - /* Don't assign ID to metadata. */ - if (ua_chan->attr.type == LTTNG_UST_CHAN_METADATA) { - chan_id = -1U; + /* Depending on the buffer type, a different channel key is used. */ + if (ua_sess->buffer_type == LTTNG_BUFFER_PER_UID) { + chan_reg_key = ua_chan->tracing_channel_id; } else { - chan_id = ust_registry_get_next_chan_id(&ua_chan->session->registry); + chan_reg_key = ua_chan->key; } - reg_count = ust_registry_get_event_count(&ua_chan->registry); - if (reg_count < 31) { - type = USTCTL_CHANNEL_HEADER_COMPACT; + pthread_mutex_lock(®istry->lock); + + chan_reg = ust_registry_channel_find(registry, chan_reg_key); + assert(chan_reg); + + if (!chan_reg->register_done) { + reg_count = ust_registry_get_event_count(chan_reg); + if (reg_count < 31) { + type = USTCTL_CHANNEL_HEADER_COMPACT; + } else { + type = USTCTL_CHANNEL_HEADER_LARGE; + } + + chan_reg->nr_ctx_fields = nr_fields; + chan_reg->ctx_fields = fields; + chan_reg->header_type = type; } else { - type = USTCTL_CHANNEL_HEADER_LARGE; + /* Get current already assigned values. */ + type = chan_reg->header_type; + free(fields); + /* Set to NULL so the error path does not do a double free. */ + fields = NULL; } - - ua_chan->registry.nr_ctx_fields = nr_fields; - ua_chan->registry.ctx_fields = fields; - ua_chan->registry.chan_id = chan_id; - ua_chan->registry.header_type = type; + /* Channel id is set during the object creation. */ + chan_id = chan_reg->chan_id; /* Append to metadata */ - if (!ret_code) { - ret_code = ust_metadata_channel_statedump(&ua_chan->session->registry, - &ua_chan->registry); + if (!chan_reg->metadata_dumped) { + ret_code = ust_metadata_channel_statedump(registry, chan_reg); if (ret_code) { ERR("Error appending channel metadata (errno = %d)", ret_code); goto reply; @@ -3593,8 +4729,9 @@ static int reply_ust_register_channel(int sock, int sobjd, int cobjd, } reply: - DBG3("UST app replying to register channel with id %u, type: %d, ret: %d", - chan_id, type, ret_code); + DBG3("UST app replying to register channel key %" PRIu64 + " with id %u, type: %d, ret: %d", chan_reg_key, chan_id, type, + ret_code); ret = ustctl_reply_register_channel(sock, chan_id, type, ret_code); if (ret < 0) { @@ -3606,10 +4743,16 @@ reply: goto error; } + /* This channel registry registration is completed. */ + chan_reg->register_done = 1; + error: - pthread_mutex_unlock(&ua_sess->registry.lock); + pthread_mutex_unlock(®istry->lock); error_rcu_unlock: rcu_read_unlock(); + if (ret) { + free(fields); + } return ret; } @@ -3628,9 +4771,11 @@ static int add_event_ust_registry(int sock, int sobjd, int cobjd, char *name, { int ret, ret_code; uint32_t event_id = 0; + uint64_t chan_reg_key; struct ust_app *app; struct ust_app_channel *ua_chan; struct ust_app_session *ua_sess; + struct ust_registry_session *registry; rcu_read_lock(); @@ -3640,20 +4785,46 @@ static int add_event_ust_registry(int sock, int sobjd, int cobjd, char *name, DBG("Application socket %d is being teardown. Abort event notify", sock); ret = 0; + free(sig); + free(fields); + free(model_emf_uri); goto error_rcu_unlock; } - /* Lookup channel by UST object descriptor. Should always be found. */ + /* Lookup channel by UST object descriptor. */ ua_chan = find_channel_by_objd(app, cobjd); - assert(ua_chan); + if (!ua_chan) { + DBG("Application channel is being teardown. Abort event notify"); + ret = 0; + free(sig); + free(fields); + free(model_emf_uri); + goto error_rcu_unlock; + } + assert(ua_chan->session); ua_sess = ua_chan->session; - pthread_mutex_lock(&ua_sess->registry.lock); + registry = get_session_registry(ua_sess); + assert(registry); + + if (ua_sess->buffer_type == LTTNG_BUFFER_PER_UID) { + chan_reg_key = ua_chan->tracing_channel_id; + } else { + chan_reg_key = ua_chan->key; + } + + pthread_mutex_lock(®istry->lock); - ret_code = ust_registry_create_event(&ua_sess->registry, - &ua_chan->registry, sobjd, cobjd, name, sig, nr_fields, fields, - loglevel, model_emf_uri, &event_id); + /* + * From this point on, this call acquires the ownership of the sig, fields + * and model_emf_uri meaning any free are done inside it if needed. These + * three variables MUST NOT be read/write after this. + */ + ret_code = ust_registry_create_event(registry, chan_reg_key, + sobjd, cobjd, name, sig, nr_fields, fields, loglevel, + model_emf_uri, ua_sess->buffer_type, &event_id, + app); /* * The return value is returned to ustctl so in case of an error, the @@ -3674,10 +4845,11 @@ static int add_event_ust_registry(int sock, int sobjd, int cobjd, char *name, goto error; } - DBG3("UST registry event %s has been added successfully", name); + DBG3("UST registry event %s with id %" PRId32 " added successfully", + name, event_id); error: - pthread_mutex_unlock(&ua_sess->registry.lock); + pthread_mutex_unlock(®istry->lock); error_rcu_unlock: rcu_read_unlock(); return ret; @@ -3726,7 +4898,12 @@ int ust_app_recv_notify(int sock) goto error; } - /* Add event to the UST registry coming from the notify socket. */ + /* + * Add event to the UST registry coming from the notify socket. This + * call will free if needed the sig, fields and model_emf_uri. This + * code path loses the ownsership of these variables and transfer them + * to the this function. + */ ret = add_event_ust_registry(sock, sobjd, cobjd, name, sig, nr_fields, fields, loglevel, model_emf_uri); if (ret < 0) { @@ -3754,6 +4931,11 @@ int ust_app_recv_notify(int sock) goto error; } + /* + * The fields ownership are transfered to this function call meaning + * that if needed it will be freed. After this, it's invalid to access + * fields or clean it up. + */ ret = reply_ust_register_channel(sock, sobjd, cobjd, nr_fields, fields); if (ret < 0) { @@ -3847,3 +5029,235 @@ close_socket: call_rcu(&obj->head, close_notify_sock_rcu); } } + +/* + * Destroy a ust app data structure and free its memory. + */ +void ust_app_destroy(struct ust_app *app) +{ + if (!app) { + return; + } + + call_rcu(&app->pid_n.head, delete_ust_app_rcu); +} + +/* + * Take a snapshot for a given UST session. The snapshot is sent to the given + * output. + * + * Return 0 on success or else a negative value. + */ +int ust_app_snapshot_record(struct ltt_ust_session *usess, + struct snapshot_output *output, int wait, unsigned int nb_streams) +{ + int ret = 0; + struct lttng_ht_iter iter; + struct ust_app *app; + char pathname[PATH_MAX]; + uint64_t max_stream_size = 0; + + assert(usess); + assert(output); + + rcu_read_lock(); + + /* + * Compute the maximum size of a single stream if a max size is asked by + * the caller. + */ + if (output->max_size > 0 && nb_streams > 0) { + max_stream_size = output->max_size / nb_streams; + } + + switch (usess->buffer_type) { + case LTTNG_BUFFER_PER_UID: + { + struct buffer_reg_uid *reg; + + cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) { + struct buffer_reg_channel *reg_chan; + struct consumer_socket *socket; + + /* Get consumer socket to use to push the metadata.*/ + socket = consumer_find_socket_by_bitness(reg->bits_per_long, + usess->consumer); + if (!socket) { + ret = -EINVAL; + goto error; + } + + memset(pathname, 0, sizeof(pathname)); + ret = snprintf(pathname, sizeof(pathname), + DEFAULT_UST_TRACE_DIR "/" DEFAULT_UST_TRACE_UID_PATH, + reg->uid, reg->bits_per_long); + if (ret < 0) { + PERROR("snprintf snapshot path"); + goto error; + } + + /* Add the UST default trace dir to path. */ + cds_lfht_for_each_entry(reg->registry->channels->ht, &iter.iter, + reg_chan, node.node) { + + /* + * Make sure the maximum stream size is not lower than the + * subbuffer size or else it's an error since we won't be able to + * snapshot anything. + */ + if (max_stream_size && + reg_chan->subbuf_size > max_stream_size) { + ret = -EINVAL; + DBG3("UST app snapshot record maximum stream size %" PRIu64 + " is smaller than subbuffer size of %zu", + max_stream_size, reg_chan->subbuf_size); + goto error; + } + ret = consumer_snapshot_channel(socket, reg_chan->consumer_key, output, 0, + usess->uid, usess->gid, pathname, wait, + max_stream_size); + if (ret < 0) { + goto error; + } + } + ret = consumer_snapshot_channel(socket, reg->registry->reg.ust->metadata_key, output, + 1, usess->uid, usess->gid, pathname, wait, + max_stream_size); + if (ret < 0) { + goto error; + } + } + break; + } + case LTTNG_BUFFER_PER_PID: + { + cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) { + struct consumer_socket *socket; + struct lttng_ht_iter chan_iter; + struct ust_app_channel *ua_chan; + struct ust_app_session *ua_sess; + struct ust_registry_session *registry; + + ua_sess = lookup_session_by_app(usess, app); + if (!ua_sess) { + /* Session not associated with this app. */ + continue; + } + + /* Get the right consumer socket for the application. */ + socket = consumer_find_socket_by_bitness(app->bits_per_long, + output->consumer); + if (!socket) { + ret = -EINVAL; + goto error; + } + + /* Add the UST default trace dir to path. */ + memset(pathname, 0, sizeof(pathname)); + ret = snprintf(pathname, sizeof(pathname), DEFAULT_UST_TRACE_DIR "/%s", + ua_sess->path); + if (ret < 0) { + PERROR("snprintf snapshot path"); + goto error; + } + + cds_lfht_for_each_entry(ua_sess->channels->ht, &chan_iter.iter, + ua_chan, node.node) { + /* + * Make sure the maximum stream size is not lower than the + * subbuffer size or else it's an error since we won't be able to + * snapshot anything. + */ + if (max_stream_size && + ua_chan->attr.subbuf_size > max_stream_size) { + ret = -EINVAL; + DBG3("UST app snapshot record maximum stream size %" PRIu64 + " is smaller than subbuffer size of %" PRIu64, + max_stream_size, ua_chan->attr.subbuf_size); + goto error; + } + + ret = consumer_snapshot_channel(socket, ua_chan->key, output, 0, + ua_sess->euid, ua_sess->egid, pathname, wait, + max_stream_size); + if (ret < 0) { + goto error; + } + } + + registry = get_session_registry(ua_sess); + assert(registry); + ret = consumer_snapshot_channel(socket, registry->metadata_key, output, + 1, ua_sess->euid, ua_sess->egid, pathname, wait, + max_stream_size); + if (ret < 0) { + goto error; + } + } + break; + } + default: + assert(0); + break; + } + +error: + rcu_read_unlock(); + return ret; +} + +/* + * Return the number of streams for a UST session. + */ +unsigned int ust_app_get_nb_stream(struct ltt_ust_session *usess) +{ + unsigned int ret = 0; + struct ust_app *app; + struct lttng_ht_iter iter; + + assert(usess); + + switch (usess->buffer_type) { + case LTTNG_BUFFER_PER_UID: + { + struct buffer_reg_uid *reg; + + cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) { + struct buffer_reg_channel *reg_chan; + + cds_lfht_for_each_entry(reg->registry->channels->ht, &iter.iter, + reg_chan, node.node) { + ret += reg_chan->stream_count; + } + } + break; + } + case LTTNG_BUFFER_PER_PID: + { + rcu_read_lock(); + cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) { + struct ust_app_channel *ua_chan; + struct ust_app_session *ua_sess; + struct lttng_ht_iter chan_iter; + + ua_sess = lookup_session_by_app(usess, app); + if (!ua_sess) { + /* Session not associated with this app. */ + continue; + } + + cds_lfht_for_each_entry(ua_sess->channels->ht, &chan_iter.iter, + ua_chan, node.node) { + ret += ua_chan->streams.count; + } + } + rcu_read_unlock(); + break; + } + default: + assert(0); + break; + } + + return ret; +}