X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fnotification-thread-events.c;h=285bcf951aafe3a5bb2801777e7a13eb06dc5ec7;hp=254aa5396e5d30c102e771545773645ad766311c;hb=505b2d90aa87592186ecc2a119cf67fb3f90d168;hpb=8abe313a6c4f251063e4b72ddd47ce8107384d71 diff --git a/src/bin/lttng-sessiond/notification-thread-events.c b/src/bin/lttng-sessiond/notification-thread-events.c index 254aa5396..285bcf951 100644 --- a/src/bin/lttng-sessiond/notification-thread-events.c +++ b/src/bin/lttng-sessiond/notification-thread-events.c @@ -1,18 +1,8 @@ /* - * Copyright (C) 2017 - Jérémie Galarneau + * Copyright (C) 2017 Jérémie Galarneau * - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License, version 2 only, as - * published by the Free Software Foundation. + * SPDX-License-Identifier: GPL-2.0-only * - * This program is distributed in the hope that it will be useful, but WITHOUT - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for - * more details. - * - * You should have received a copy of the GNU General Public License along with - * this program; if not, write to the Free Software Foundation, Inc., 51 - * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ #define _LGPL_SOURCE @@ -28,10 +18,12 @@ #include #include #include -#include +#include #include #include #include +#include +#include #include #include @@ -49,20 +41,75 @@ #define CLIENT_POLL_MASK_IN (LPOLLIN | LPOLLERR | LPOLLHUP | LPOLLRDHUP) #define CLIENT_POLL_MASK_IN_OUT (CLIENT_POLL_MASK_IN | LPOLLOUT) +enum lttng_object_type { + LTTNG_OBJECT_TYPE_UNKNOWN, + LTTNG_OBJECT_TYPE_NONE, + LTTNG_OBJECT_TYPE_CHANNEL, + LTTNG_OBJECT_TYPE_SESSION, +}; + struct lttng_trigger_list_element { - struct lttng_trigger *trigger; + /* No ownership of the trigger object is assumed. */ + const struct lttng_trigger *trigger; struct cds_list_head node; }; struct lttng_channel_trigger_list { struct channel_key channel_key; + /* List of struct lttng_trigger_list_element. */ struct cds_list_head list; + /* Node in the channel_triggers_ht */ struct cds_lfht_node channel_triggers_ht_node; + /* call_rcu delayed reclaim. */ + struct rcu_head rcu_node; +}; + +/* + * List of triggers applying to a given session. + * + * See: + * - lttng_session_trigger_list_create() + * - lttng_session_trigger_list_build() + * - lttng_session_trigger_list_destroy() + * - lttng_session_trigger_list_add() + */ +struct lttng_session_trigger_list { + /* + * Not owned by this; points to the session_info structure's + * session name. + */ + const char *session_name; + /* List of struct lttng_trigger_list_element. */ + struct cds_list_head list; + /* Node in the session_triggers_ht */ + struct cds_lfht_node session_triggers_ht_node; + /* + * Weak reference to the notification system's session triggers + * hashtable. + * + * The session trigger list structure structure is owned by + * the session's session_info. + * + * The session_info is kept alive the the channel_infos holding a + * reference to it (reference counting). When those channels are + * destroyed (at runtime or on teardown), the reference they hold + * to the session_info are released. On destruction of session_info, + * session_info_destroy() will remove the list of triggers applying + * to this session from the notification system's state. + * + * This implies that the session_triggers_ht must be destroyed + * after the channels. + */ + struct cds_lfht *session_triggers_ht; + /* Used for delayed RCU reclaim. */ + struct rcu_head rcu_node; }; struct lttng_trigger_ht_element { struct lttng_trigger *trigger; struct cds_lfht_node node; + /* call_rcu delayed reclaim. */ + struct rcu_head rcu_node; }; struct lttng_condition_list_element { @@ -75,13 +122,41 @@ struct notification_client_list_element { struct cds_list_head node; }; +/* + * Thread safety of notification_client and notification_client_list. + * + * The notification thread (main thread) and the action executor + * interact through client lists. Hence, when the action executor + * thread looks-up the list of clients subscribed to a given + * condition, it will acquire a reference to the list and lock it + * while attempting to communicate with the various clients. + * + * It is not necessary to reference-count clients as they are guaranteed + * to be 'alive' if they are present in a list and that list is locked. Indeed, + * removing references to the client from those subscription lists is part of + * the work performed on destruction of a client. + * + * No provision for other access scenarios are taken into account; + * this is the bare minimum to make these accesses safe and the + * notification thread's state is _not_ "thread-safe" in any general + * sense. + */ struct notification_client_list { - struct lttng_trigger *trigger; + pthread_mutex_t lock; + struct urcu_ref ref; + const struct lttng_trigger *trigger; struct cds_list_head list; - struct cds_lfht_node notification_trigger_ht_node; + /* Weak reference to container. */ + struct cds_lfht *notification_trigger_clients_ht; + struct cds_lfht_node notification_trigger_clients_ht_node; + /* call_rcu delayed reclaim. */ + struct rcu_head rcu_node; }; struct notification_client { + /* Nests within the notification_client_list lock. */ + pthread_mutex_t lock; + notification_client_id id; int socket; /* Client protocol version. */ uint8_t major, minor; @@ -99,7 +174,16 @@ struct notification_client { */ struct cds_list_head condition_list; struct cds_lfht_node client_socket_ht_node; + struct cds_lfht_node client_id_ht_node; struct { + /* + * If a client's communication is inactive, it means that a + * fatal error has occurred (could be either a protocol error or + * the socket API returned a fatal error). No further + * communication should be attempted; the client is queued for + * clean-up. + */ + bool active; struct { /* * During the reception of a message, the reception @@ -145,6 +229,8 @@ struct notification_client { struct lttng_dynamic_buffer buffer; } outbound; } communication; + /* call_rcu delayed reclaim. */ + struct rcu_head rcu_node; }; struct channel_state_sample { @@ -152,23 +238,29 @@ struct channel_state_sample { struct cds_lfht_node channel_state_ht_node; uint64_t highest_usage; uint64_t lowest_usage; + uint64_t channel_total_consumed; + /* call_rcu delayed reclaim. */ + struct rcu_head rcu_node; }; static unsigned long hash_channel_key(struct channel_key *key); -static int evaluate_condition(struct lttng_condition *condition, +static int evaluate_buffer_condition(const struct lttng_condition *condition, struct lttng_evaluation **evaluation, - struct notification_thread_state *state, - struct channel_state_sample *previous_sample, - struct channel_state_sample *latest_sample, - uint64_t buffer_capacity); + const struct notification_thread_state *state, + const struct channel_state_sample *previous_sample, + const struct channel_state_sample *latest_sample, + uint64_t previous_session_consumed_total, + uint64_t latest_session_consumed_total, + struct channel_info *channel_info); static -int send_evaluation_to_clients(struct lttng_trigger *trigger, - struct lttng_evaluation *evaluation, +int send_evaluation_to_clients(const struct lttng_trigger *trigger, + const struct lttng_evaluation *evaluation, struct notification_client_list *client_list, struct notification_thread_state *state, uid_t channel_uid, gid_t channel_gid); +/* session_info API */ static void session_info_destroy(void *_data); static @@ -177,7 +269,9 @@ static void session_info_put(struct session_info *session_info); static struct session_info *session_info_create(const char *name, - uid_t uid, gid_t gid); + uid_t uid, gid_t gid, + struct lttng_session_trigger_list *trigger_list, + struct cds_lfht *sessions_ht); static void session_info_add_channel(struct session_info *session_info, struct channel_info *channel_info); @@ -185,17 +279,43 @@ static void session_info_remove_channel(struct session_info *session_info, struct channel_info *channel_info); +/* lttng_session_trigger_list API */ +static +struct lttng_session_trigger_list *lttng_session_trigger_list_create( + const char *session_name, + struct cds_lfht *session_triggers_ht); +static +struct lttng_session_trigger_list *lttng_session_trigger_list_build( + const struct notification_thread_state *state, + const char *session_name); +static +void lttng_session_trigger_list_destroy( + struct lttng_session_trigger_list *list); +static +int lttng_session_trigger_list_add(struct lttng_session_trigger_list *list, + const struct lttng_trigger *trigger); + + static -int match_client(struct cds_lfht_node *node, const void *key) +int match_client_socket(struct cds_lfht_node *node, const void *key) { /* This double-cast is intended to supress pointer-to-cast warning. */ - int socket = (int) (intptr_t) key; - struct notification_client *client; + const int socket = (int) (intptr_t) key; + const struct notification_client *client = caa_container_of(node, + struct notification_client, client_socket_ht_node); - client = caa_container_of(node, struct notification_client, - client_socket_ht_node); + return client->socket == socket; +} + +static +int match_client_id(struct cds_lfht_node *node, const void *key) +{ + /* This double-cast is intended to supress pointer-to-cast warning. */ + const notification_client_id id = *((notification_client_id *) key); + const struct notification_client *client = caa_container_of( + node, struct notification_client, client_id_ht_node); - return !!(client->socket == socket); + return client->id == id; } static @@ -211,6 +331,18 @@ int match_channel_trigger_list(struct cds_lfht_node *node, const void *key) (channel_key->domain == trigger_list->channel_key.domain)); } +static +int match_session_trigger_list(struct cds_lfht_node *node, const void *key) +{ + const char *session_name = (const char *) key; + struct lttng_session_trigger_list *trigger_list; + + trigger_list = caa_container_of(node, struct lttng_session_trigger_list, + session_triggers_ht_node); + + return !!(strcmp(trigger_list->session_name, session_name) == 0); +} + static int match_channel_state_sample(struct cds_lfht_node *node, const void *key) { @@ -253,49 +385,44 @@ int match_condition(struct cds_lfht_node *node, const void *key) } static -int match_client_list(struct cds_lfht_node *node, const void *key) +int match_client_list_condition(struct cds_lfht_node *node, const void *key) { - struct lttng_trigger *trigger_key = (struct lttng_trigger *) key; + struct lttng_condition *condition_key = (struct lttng_condition *) key; struct notification_client_list *client_list; - struct lttng_condition *condition; - struct lttng_condition *condition_key = lttng_trigger_get_condition( - trigger_key); + const struct lttng_condition *condition; assert(condition_key); client_list = caa_container_of(node, struct notification_client_list, - notification_trigger_ht_node); - condition = lttng_trigger_get_condition(client_list->trigger); + notification_trigger_clients_ht_node); + condition = lttng_trigger_get_const_condition(client_list->trigger); return !!lttng_condition_is_equal(condition_key, condition); } static -int match_client_list_condition(struct cds_lfht_node *node, const void *key) +int match_session(struct cds_lfht_node *node, const void *key) { - struct lttng_condition *condition_key = (struct lttng_condition *) key; - struct notification_client_list *client_list; - struct lttng_condition *condition; - - assert(condition_key); - - client_list = caa_container_of(node, struct notification_client_list, - notification_trigger_ht_node); - condition = lttng_trigger_get_condition(client_list->trigger); + const char *name = key; + struct session_info *session_info = caa_container_of( + node, struct session_info, sessions_ht_node); - return !!lttng_condition_is_equal(condition_key, condition); + return !strcmp(session_info->name, name); } static unsigned long lttng_condition_buffer_usage_hash( - struct lttng_condition *_condition) + const struct lttng_condition *_condition) { - unsigned long hash = 0; + unsigned long hash; + unsigned long condition_type; struct lttng_condition_buffer_usage *condition; condition = container_of(_condition, struct lttng_condition_buffer_usage, parent); + condition_type = (unsigned long) condition->parent.type; + hash = hash_key_ulong((void *) condition_type, lttng_ht_seed); if (condition->session_name) { hash ^= hash_key_str(condition->session_name, lttng_ht_seed); } @@ -321,18 +448,61 @@ unsigned long lttng_condition_buffer_usage_hash( return hash; } +static +unsigned long lttng_condition_session_consumed_size_hash( + const struct lttng_condition *_condition) +{ + unsigned long hash; + unsigned long condition_type = + (unsigned long) LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE; + struct lttng_condition_session_consumed_size *condition; + uint64_t val; + + condition = container_of(_condition, + struct lttng_condition_session_consumed_size, parent); + + hash = hash_key_ulong((void *) condition_type, lttng_ht_seed); + if (condition->session_name) { + hash ^= hash_key_str(condition->session_name, lttng_ht_seed); + } + val = condition->consumed_threshold_bytes.value; + hash ^= hash_key_u64(&val, lttng_ht_seed); + return hash; +} + +static +unsigned long lttng_condition_session_rotation_hash( + const struct lttng_condition *_condition) +{ + unsigned long hash, condition_type; + struct lttng_condition_session_rotation *condition; + + condition = container_of(_condition, + struct lttng_condition_session_rotation, parent); + condition_type = (unsigned long) condition->parent.type; + hash = hash_key_ulong((void *) condition_type, lttng_ht_seed); + assert(condition->session_name); + hash ^= hash_key_str(condition->session_name, lttng_ht_seed); + return hash; +} + /* * The lttng_condition hashing code is kept in this file (rather than * condition.c) since it makes use of GPLv2 code (hashtable utils), which we * don't want to link in liblttng-ctl. */ static -unsigned long lttng_condition_hash(struct lttng_condition *condition) +unsigned long lttng_condition_hash(const struct lttng_condition *condition) { switch (condition->type) { case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW: case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH: return lttng_condition_buffer_usage_hash(condition); + case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE: + return lttng_condition_session_consumed_size_hash(condition); + case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING: + case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED: + return lttng_condition_session_rotation_hash(condition); default: ERR("[notification-thread] Unexpected condition type caught"); abort(); @@ -349,6 +519,49 @@ unsigned long hash_channel_key(struct channel_key *key) return key_hash ^ domain_hash; } +static +unsigned long hash_client_socket(int socket) +{ + return hash_key_ulong((void *) (unsigned long) socket, lttng_ht_seed); +} + +static +unsigned long hash_client_id(notification_client_id id) +{ + return hash_key_u64(&id, lttng_ht_seed); +} + +/* + * Get the type of object to which a given condition applies. Bindings let + * the notification system evaluate a trigger's condition when a given + * object's state is updated. + * + * For instance, a condition bound to a channel will be evaluated everytime + * the channel's state is changed by a channel monitoring sample. + */ +static +enum lttng_object_type get_condition_binding_object( + const struct lttng_condition *condition) +{ + switch (lttng_condition_get_type(condition)) { + case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW: + case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH: + case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE: + return LTTNG_OBJECT_TYPE_CHANNEL; + case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING: + case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED: + return LTTNG_OBJECT_TYPE_SESSION; + default: + return LTTNG_OBJECT_TYPE_UNKNOWN; + } +} + +static +void free_channel_info_rcu(struct rcu_head *node) +{ + free(caa_container_of(node, struct channel_info, rcu_node)); +} + static void channel_info_destroy(struct channel_info *channel_info) { @@ -364,7 +577,13 @@ void channel_info_destroy(struct channel_info *channel_info) if (channel_info->name) { free(channel_info->name); } - free(channel_info); + call_rcu(&channel_info->rcu_node, free_channel_info_rcu); +} + +static +void free_session_info_rcu(struct rcu_head *node) +{ + free(caa_container_of(node, struct session_info, rcu_node)); } /* Don't call directly, use the ref-counting mechanism. */ @@ -372,13 +591,23 @@ static void session_info_destroy(void *_data) { struct session_info *session_info = _data; + int ret; assert(session_info); if (session_info->channel_infos_ht) { - cds_lfht_destroy(session_info->channel_infos_ht, NULL); + ret = cds_lfht_destroy(session_info->channel_infos_ht, NULL); + if (ret) { + ERR("[notification-thread] Failed to destroy channel information hash table"); + } } + lttng_session_trigger_list_destroy(session_info->trigger_list); + + rcu_read_lock(); + cds_lfht_del(session_info->sessions_ht, + &session_info->sessions_ht_node); + rcu_read_unlock(); free(session_info->name); - free(session_info); + call_rcu(&session_info->rcu_node, free_session_info_rcu); } static @@ -400,7 +629,9 @@ void session_info_put(struct session_info *session_info) } static -struct session_info *session_info_create(const char *name, uid_t uid, gid_t gid) +struct session_info *session_info_create(const char *name, uid_t uid, gid_t gid, + struct lttng_session_trigger_list *trigger_list, + struct cds_lfht *sessions_ht) { struct session_info *session_info; @@ -425,6 +656,8 @@ struct session_info *session_info_create(const char *name, uid_t uid, gid_t gid) } session_info->uid = uid; session_info->gid = gid; + session_info->trigger_list = trigger_list; + session_info->sessions_ht = sessions_ht; end: return session_info; error: @@ -489,12 +722,122 @@ error: return NULL; } -/* This function must be called with the RCU read lock held. */ static -int evaluate_condition_for_client(struct lttng_trigger *trigger, - struct lttng_condition *condition, - struct notification_client *client, - struct notification_thread_state *state) +bool notification_client_list_get(struct notification_client_list *list) +{ + return urcu_ref_get_unless_zero(&list->ref); +} + +static +void free_notification_client_list_rcu(struct rcu_head *node) +{ + free(caa_container_of(node, struct notification_client_list, + rcu_node)); +} + +static +void notification_client_list_release(struct urcu_ref *list_ref) +{ + struct notification_client_list *list = + container_of(list_ref, typeof(*list), ref); + struct notification_client_list_element *client_list_element, *tmp; + + if (list->notification_trigger_clients_ht) { + rcu_read_lock(); + cds_lfht_del(list->notification_trigger_clients_ht, + &list->notification_trigger_clients_ht_node); + rcu_read_unlock(); + list->notification_trigger_clients_ht = NULL; + } + cds_list_for_each_entry_safe(client_list_element, tmp, + &list->list, node) { + free(client_list_element); + } + pthread_mutex_destroy(&list->lock); + call_rcu(&list->rcu_node, free_notification_client_list_rcu); +} + +static +struct notification_client_list *notification_client_list_create( + const struct lttng_trigger *trigger) +{ + struct notification_client_list *client_list = + zmalloc(sizeof(*client_list)); + + if (!client_list) { + goto error; + } + pthread_mutex_init(&client_list->lock, NULL); + urcu_ref_init(&client_list->ref); + cds_lfht_node_init(&client_list->notification_trigger_clients_ht_node); + CDS_INIT_LIST_HEAD(&client_list->list); + client_list->trigger = trigger; +error: + return client_list; +} + +static +void publish_notification_client_list( + struct notification_thread_state *state, + struct notification_client_list *list) +{ + const struct lttng_condition *condition = + lttng_trigger_get_const_condition(list->trigger); + + assert(!list->notification_trigger_clients_ht); + + list->notification_trigger_clients_ht = + state->notification_trigger_clients_ht; + + rcu_read_lock(); + cds_lfht_add(state->notification_trigger_clients_ht, + lttng_condition_hash(condition), + &list->notification_trigger_clients_ht_node); + rcu_read_unlock(); +} + +static +void notification_client_list_put(struct notification_client_list *list) +{ + if (!list) { + return; + } + return urcu_ref_put(&list->ref, notification_client_list_release); +} + +/* Provides a reference to the returned list. */ +static +struct notification_client_list *get_client_list_from_condition( + struct notification_thread_state *state, + const struct lttng_condition *condition) +{ + struct cds_lfht_node *node; + struct cds_lfht_iter iter; + struct notification_client_list *list = NULL; + + rcu_read_lock(); + cds_lfht_lookup(state->notification_trigger_clients_ht, + lttng_condition_hash(condition), + match_client_list_condition, + condition, + &iter); + node = cds_lfht_iter_get_node(&iter); + if (node) { + list = container_of(node, struct notification_client_list, + notification_trigger_clients_ht_node); + list = notification_client_list_get(list) ? list : NULL; + } + + rcu_read_unlock(); + return list; +} + +static +int evaluate_channel_condition_for_client( + const struct lttng_condition *condition, + struct notification_thread_state *state, + struct lttng_evaluation **evaluation, + uid_t *session_uid, gid_t *session_gid) { int ret; struct cds_lfht_iter iter; @@ -503,23 +846,17 @@ int evaluate_condition_for_client(struct lttng_trigger *trigger, struct channel_key *channel_key = NULL; struct channel_state_sample *last_sample = NULL; struct lttng_channel_trigger_list *channel_trigger_list = NULL; - struct lttng_evaluation *evaluation = NULL; - struct notification_client_list client_list = { 0 }; - struct notification_client_list_element client_list_element = { 0 }; - assert(trigger); - assert(condition); - assert(client); - assert(state); + rcu_read_lock(); - /* Find the channel associated with the trigger. */ + /* Find the channel associated with the condition. */ cds_lfht_for_each_entry(state->channel_triggers_ht, &iter, - channel_trigger_list , channel_triggers_ht_node) { + channel_trigger_list, channel_triggers_ht_node) { struct lttng_trigger_list_element *element; cds_list_for_each_entry(element, &channel_trigger_list->list, node) { - struct lttng_condition *current_condition = - lttng_trigger_get_condition( + const struct lttng_condition *current_condition = + lttng_trigger_get_const_condition( element->trigger); assert(current_condition); @@ -540,7 +877,7 @@ int evaluate_condition_for_client(struct lttng_trigger *trigger, if (!channel_key){ /* No channel found; normal exit. */ - DBG("[notification-thread] No channel associated with newly subscribed-to condition"); + DBG("[notification-thread] No known channel associated with newly subscribed-to condition"); ret = 0; goto end; } @@ -574,66 +911,216 @@ int evaluate_condition_for_client(struct lttng_trigger *trigger, goto end; } - ret = evaluate_condition(condition, &evaluation, state, NULL, - last_sample, channel_info->capacity); + ret = evaluate_buffer_condition(condition, evaluation, state, + NULL, last_sample, + 0, channel_info->session_info->consumed_data_size, + channel_info); if (ret) { WARN("[notification-thread] Fatal error occurred while evaluating a newly subscribed-to condition"); goto end; } - if (!evaluation) { - /* Evaluation yielded nothing. Normal exit. */ - DBG("[notification-thread] Newly subscribed-to condition evaluated to false, nothing to report to client"); - ret = 0; - goto end; - } - - /* - * Create a temporary client list with the client currently - * subscribing. - */ - cds_lfht_node_init(&client_list.notification_trigger_ht_node); - CDS_INIT_LIST_HEAD(&client_list.list); - client_list.trigger = trigger; - - CDS_INIT_LIST_HEAD(&client_list_element.node); - client_list_element.client = client; - cds_list_add(&client_list_element.node, &client_list.list); + *session_uid = channel_info->session_info->uid; + *session_gid = channel_info->session_info->gid; +end: + rcu_read_unlock(); + return ret; +} - /* Send evaluation result to the newly-subscribed client. */ - DBG("[notification-thread] Newly subscribed-to condition evaluated to true, notifying client"); - ret = send_evaluation_to_clients(trigger, evaluation, &client_list, - state, channel_info->session_info->uid, - channel_info->session_info->gid); +static +const char *get_condition_session_name(const struct lttng_condition *condition) +{ + const char *session_name = NULL; + enum lttng_condition_status status; + switch (lttng_condition_get_type(condition)) { + case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW: + case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH: + status = lttng_condition_buffer_usage_get_session_name( + condition, &session_name); + break; + case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE: + status = lttng_condition_session_consumed_size_get_session_name( + condition, &session_name); + break; + case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING: + case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED: + status = lttng_condition_session_rotation_get_session_name( + condition, &session_name); + break; + default: + abort(); + } + if (status != LTTNG_CONDITION_STATUS_OK) { + ERR("[notification-thread] Failed to retrieve session rotation condition's session name"); + goto end; + } end: - return ret; + return session_name; } static -int notification_thread_client_subscribe(struct notification_client *client, - struct lttng_condition *condition, +int evaluate_session_condition_for_client( + const struct lttng_condition *condition, struct notification_thread_state *state, - enum lttng_notification_channel_status *_status) + struct lttng_evaluation **evaluation, + uid_t *session_uid, gid_t *session_gid) { - int ret = 0; + int ret; struct cds_lfht_iter iter; struct cds_lfht_node *node; - struct notification_client_list *client_list; - struct lttng_condition_list_element *condition_list_element = NULL; - struct notification_client_list_element *client_list_element = NULL; - enum lttng_notification_channel_status status = - LTTNG_NOTIFICATION_CHANNEL_STATUS_OK; + const char *session_name; + struct session_info *session_info = NULL; - /* - * Ensure that the client has not already subscribed to this condition - * before. - */ - cds_list_for_each_entry(condition_list_element, &client->condition_list, node) { - if (lttng_condition_is_equal(condition_list_element->condition, - condition)) { - status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ALREADY_SUBSCRIBED; - goto end; + rcu_read_lock(); + session_name = get_condition_session_name(condition); + + /* Find the session associated with the trigger. */ + cds_lfht_lookup(state->sessions_ht, + hash_key_str(session_name, lttng_ht_seed), + match_session, + session_name, + &iter); + node = cds_lfht_iter_get_node(&iter); + if (!node) { + DBG("[notification-thread] No known session matching name \"%s\"", + session_name); + ret = 0; + goto end; + } + + session_info = caa_container_of(node, struct session_info, + sessions_ht_node); + session_info_get(session_info); + + /* + * Evaluation is performed in-line here since only one type of + * session-bound condition is handled for the moment. + */ + switch (lttng_condition_get_type(condition)) { + case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING: + if (!session_info->rotation.ongoing) { + ret = 0; + goto end_session_put; + } + + *evaluation = lttng_evaluation_session_rotation_ongoing_create( + session_info->rotation.id); + if (!*evaluation) { + /* Fatal error. */ + ERR("[notification-thread] Failed to create session rotation ongoing evaluation for session \"%s\"", + session_info->name); + ret = -1; + goto end_session_put; + } + ret = 0; + break; + default: + ret = 0; + goto end_session_put; + } + + *session_uid = session_info->uid; + *session_gid = session_info->gid; + +end_session_put: + session_info_put(session_info); +end: + rcu_read_unlock(); + return ret; +} + +static +int evaluate_condition_for_client(const struct lttng_trigger *trigger, + const struct lttng_condition *condition, + struct notification_client *client, + struct notification_thread_state *state) +{ + int ret; + struct lttng_evaluation *evaluation = NULL; + struct notification_client_list client_list = { + .lock = PTHREAD_MUTEX_INITIALIZER, + }; + struct notification_client_list_element client_list_element = { 0 }; + uid_t object_uid = 0; + gid_t object_gid = 0; + + assert(trigger); + assert(condition); + assert(client); + assert(state); + + switch (get_condition_binding_object(condition)) { + case LTTNG_OBJECT_TYPE_SESSION: + ret = evaluate_session_condition_for_client(condition, state, + &evaluation, &object_uid, &object_gid); + break; + case LTTNG_OBJECT_TYPE_CHANNEL: + ret = evaluate_channel_condition_for_client(condition, state, + &evaluation, &object_uid, &object_gid); + break; + case LTTNG_OBJECT_TYPE_NONE: + ret = 0; + goto end; + case LTTNG_OBJECT_TYPE_UNKNOWN: + default: + ret = -1; + goto end; + } + if (ret) { + /* Fatal error. */ + goto end; + } + if (!evaluation) { + /* Evaluation yielded nothing. Normal exit. */ + DBG("[notification-thread] Newly subscribed-to condition evaluated to false, nothing to report to client"); + ret = 0; + goto end; + } + + /* + * Create a temporary client list with the client currently + * subscribing. + */ + cds_lfht_node_init(&client_list.notification_trigger_clients_ht_node); + CDS_INIT_LIST_HEAD(&client_list.list); + client_list.trigger = trigger; + + CDS_INIT_LIST_HEAD(&client_list_element.node); + client_list_element.client = client; + cds_list_add(&client_list_element.node, &client_list.list); + + /* Send evaluation result to the newly-subscribed client. */ + DBG("[notification-thread] Newly subscribed-to condition evaluated to true, notifying client"); + ret = send_evaluation_to_clients(trigger, evaluation, &client_list, + state, object_uid, object_gid); + +end: + return ret; +} + +static +int notification_thread_client_subscribe(struct notification_client *client, + struct lttng_condition *condition, + struct notification_thread_state *state, + enum lttng_notification_channel_status *_status) +{ + int ret = 0; + struct notification_client_list *client_list = NULL; + struct lttng_condition_list_element *condition_list_element = NULL; + struct notification_client_list_element *client_list_element = NULL; + enum lttng_notification_channel_status status = + LTTNG_NOTIFICATION_CHANNEL_STATUS_OK; + + /* + * Ensure that the client has not already subscribed to this condition + * before. + */ + cds_list_for_each_entry(condition_list_element, &client->condition_list, node) { + if (lttng_condition_is_equal(condition_list_element->condition, + condition)) { + status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ALREADY_SUBSCRIBED; + goto end; } } @@ -648,8 +1135,6 @@ int notification_thread_client_subscribe(struct notification_client *client, goto error; } - rcu_read_lock(); - /* * Add the newly-subscribed condition to the client's subscription list. */ @@ -657,34 +1142,32 @@ int notification_thread_client_subscribe(struct notification_client *client, condition_list_element->condition = condition; cds_list_add(&condition_list_element->node, &client->condition_list); - cds_lfht_lookup(state->notification_trigger_clients_ht, - lttng_condition_hash(condition), - match_client_list_condition, - condition, - &iter); - node = cds_lfht_iter_get_node(&iter); - if (!node) { + client_list = get_client_list_from_condition(state, condition); + if (!client_list) { /* * No notification-emiting trigger registered with this * condition. We don't evaluate the condition right away * since this trigger is not registered yet. */ free(client_list_element); - goto end_unlock; + goto end; } - client_list = caa_container_of(node, struct notification_client_list, - notification_trigger_ht_node); /* * The condition to which the client just subscribed is evaluated * at this point so that conditions that are already TRUE result * in a notification being sent out. + * + * The client_list's trigger is used without locking the list itself. + * This is correct since the list doesn't own the trigger and the + * object is immutable. */ if (evaluate_condition_for_client(client_list->trigger, condition, client, state)) { WARN("[notification-thread] Evaluation of a condition on client subscription failed, aborting."); ret = -1; - goto end_unlock; + free(client_list_element); + goto end; } /* @@ -694,13 +1177,17 @@ int notification_thread_client_subscribe(struct notification_client *client, */ client_list_element->client = client; CDS_INIT_LIST_HEAD(&client_list_element->node); + + pthread_mutex_lock(&client_list->lock); cds_list_add(&client_list_element->node, &client_list->list); -end_unlock: - rcu_read_unlock(); + pthread_mutex_unlock(&client_list->lock); end: if (_status) { *_status = status; } + if (client_list) { + notification_client_list_put(client_list); + } return ret; error: free(condition_list_element); @@ -715,8 +1202,6 @@ int notification_thread_client_unsubscribe( struct notification_thread_state *state, enum lttng_notification_channel_status *_status) { - struct cds_lfht_iter iter; - struct cds_lfht_node *node; struct notification_client_list *client_list; struct lttng_condition_list_element *condition_list_element, *condition_tmp; @@ -758,30 +1243,24 @@ int notification_thread_client_unsubscribe( * Remove the client from the list of clients interested the trigger * matching the condition. */ - rcu_read_lock(); - cds_lfht_lookup(state->notification_trigger_clients_ht, - lttng_condition_hash(condition), - match_client_list_condition, - condition, - &iter); - node = cds_lfht_iter_get_node(&iter); - if (!node) { - goto end_unlock; + client_list = get_client_list_from_condition(state, condition); + if (!client_list) { + goto end; } - client_list = caa_container_of(node, struct notification_client_list, - notification_trigger_ht_node); + pthread_mutex_lock(&client_list->lock); cds_list_for_each_entry_safe(client_list_element, client_tmp, &client_list->list, node) { - if (client_list_element->client->socket != client->socket) { + if (client_list_element->client->id != client->id) { continue; } cds_list_del(&client_list_element->node); free(client_list_element); break; } -end_unlock: - rcu_read_unlock(); + pthread_mutex_unlock(&client_list->lock); + notification_client_list_put(client_list); + client_list = NULL; end: lttng_condition_destroy(condition); if (_status) { @@ -790,29 +1269,33 @@ end: return 0; } +static +void free_notification_client_rcu(struct rcu_head *node) +{ + free(caa_container_of(node, struct notification_client, rcu_node)); +} + static void notification_client_destroy(struct notification_client *client, struct notification_thread_state *state) { - struct lttng_condition_list_element *condition_list_element, *tmp; - if (!client) { return; } - /* Release all conditions to which the client was subscribed. */ - cds_list_for_each_entry_safe(condition_list_element, tmp, - &client->condition_list, node) { - (void) notification_thread_client_unsubscribe(client, - condition_list_element->condition, state, NULL); - } - + /* + * The client object is not reachable by other threads, no need to lock + * the client here. + */ if (client->socket >= 0) { (void) lttcomm_close_unix_sock(client->socket); + client->socket = -1; } + client->communication.active = false; lttng_dynamic_buffer_reset(&client->communication.inbound.buffer); lttng_dynamic_buffer_reset(&client->communication.outbound.buffer); - free(client); + pthread_mutex_destroy(&client->lock); + call_rcu(&client->rcu_node, free_notification_client_rcu); } /* @@ -828,8 +1311,8 @@ struct notification_client *get_client_from_socket(int socket, struct notification_client *client = NULL; cds_lfht_lookup(state->client_socket_ht, - hash_key_ulong((void *) (unsigned long) socket, lttng_ht_seed), - match_client, + hash_client_socket(socket), + match_client_socket, (void *) (unsigned long) socket, &iter); node = cds_lfht_iter_get_node(&iter); @@ -844,51 +1327,90 @@ end: } static -bool trigger_applies_to_channel(struct lttng_trigger *trigger, - struct channel_info *channel_info) +bool buffer_usage_condition_applies_to_channel( + const struct lttng_condition *condition, + const struct channel_info *channel_info) { enum lttng_condition_status status; - struct lttng_condition *condition; - const char *trigger_session_name = NULL; - const char *trigger_channel_name = NULL; - enum lttng_domain_type trigger_domain; + enum lttng_domain_type condition_domain; + const char *condition_session_name = NULL; + const char *condition_channel_name = NULL; - condition = lttng_trigger_get_condition(trigger); - if (!condition) { + status = lttng_condition_buffer_usage_get_domain_type(condition, + &condition_domain); + assert(status == LTTNG_CONDITION_STATUS_OK); + if (channel_info->key.domain != condition_domain) { goto fail; } - switch (lttng_condition_get_type(condition)) { - case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW: - case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH: - break; - default: + status = lttng_condition_buffer_usage_get_session_name( + condition, &condition_session_name); + assert((status == LTTNG_CONDITION_STATUS_OK) && condition_session_name); + + status = lttng_condition_buffer_usage_get_channel_name( + condition, &condition_channel_name); + assert((status == LTTNG_CONDITION_STATUS_OK) && condition_channel_name); + + if (strcmp(channel_info->session_info->name, condition_session_name)) { + goto fail; + } + if (strcmp(channel_info->name, condition_channel_name)) { goto fail; } - status = lttng_condition_buffer_usage_get_domain_type(condition, - &trigger_domain); - assert(status == LTTNG_CONDITION_STATUS_OK); - if (channel_info->key.domain != trigger_domain) { + return true; +fail: + return false; +} + +static +bool session_consumed_size_condition_applies_to_channel( + const struct lttng_condition *condition, + const struct channel_info *channel_info) +{ + enum lttng_condition_status status; + const char *condition_session_name = NULL; + + status = lttng_condition_session_consumed_size_get_session_name( + condition, &condition_session_name); + assert((status == LTTNG_CONDITION_STATUS_OK) && condition_session_name); + + if (strcmp(channel_info->session_info->name, condition_session_name)) { goto fail; } - status = lttng_condition_buffer_usage_get_session_name( - condition, &trigger_session_name); - assert((status == LTTNG_CONDITION_STATUS_OK) && trigger_session_name); + return true; +fail: + return false; +} - status = lttng_condition_buffer_usage_get_channel_name( - condition, &trigger_channel_name); - assert((status == LTTNG_CONDITION_STATUS_OK) && trigger_channel_name); +static +bool trigger_applies_to_channel(const struct lttng_trigger *trigger, + const struct channel_info *channel_info) +{ + const struct lttng_condition *condition; + bool trigger_applies; - if (strcmp(channel_info->session_info->name, trigger_session_name)) { + condition = lttng_trigger_get_const_condition(trigger); + if (!condition) { goto fail; } - if (strcmp(channel_info->name, trigger_channel_name)) { + + switch (lttng_condition_get_type(condition)) { + case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW: + case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH: + trigger_applies = buffer_usage_condition_applies_to_channel( + condition, channel_info); + break; + case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE: + trigger_applies = session_consumed_size_condition_applies_to_channel( + condition, channel_info); + break; + default: goto fail; } - return true; + return trigger_applies; fail: return false; } @@ -912,14 +1434,197 @@ bool trigger_applies_to_client(struct lttng_trigger *trigger, return applies; } +/* Must be called with RCU read lock held. */ static -int match_session(struct cds_lfht_node *node, const void *key) +struct lttng_session_trigger_list *get_session_trigger_list( + struct notification_thread_state *state, + const char *session_name) { - const char *name = key; - struct session_info *session_info = caa_container_of( - node, struct session_info, sessions_ht_node); + struct lttng_session_trigger_list *list = NULL; + struct cds_lfht_node *node; + struct cds_lfht_iter iter; - return !strcmp(session_info->name, name); + cds_lfht_lookup(state->session_triggers_ht, + hash_key_str(session_name, lttng_ht_seed), + match_session_trigger_list, + session_name, + &iter); + node = cds_lfht_iter_get_node(&iter); + if (!node) { + /* + * Not an error, the list of triggers applying to that session + * will be initialized when the session is created. + */ + DBG("[notification-thread] No trigger list found for session \"%s\" as it is not yet known to the notification system", + session_name); + goto end; + } + + list = caa_container_of(node, + struct lttng_session_trigger_list, + session_triggers_ht_node); +end: + return list; +} + +/* + * Allocate an empty lttng_session_trigger_list for the session named + * 'session_name'. + * + * No ownership of 'session_name' is assumed by the session trigger list. + * It is the caller's responsability to ensure the session name is alive + * for as long as this list is. + */ +static +struct lttng_session_trigger_list *lttng_session_trigger_list_create( + const char *session_name, + struct cds_lfht *session_triggers_ht) +{ + struct lttng_session_trigger_list *list; + + list = zmalloc(sizeof(*list)); + if (!list) { + goto end; + } + list->session_name = session_name; + CDS_INIT_LIST_HEAD(&list->list); + cds_lfht_node_init(&list->session_triggers_ht_node); + list->session_triggers_ht = session_triggers_ht; + + rcu_read_lock(); + /* Publish the list through the session_triggers_ht. */ + cds_lfht_add(session_triggers_ht, + hash_key_str(session_name, lttng_ht_seed), + &list->session_triggers_ht_node); + rcu_read_unlock(); +end: + return list; +} + +static +void free_session_trigger_list_rcu(struct rcu_head *node) +{ + free(caa_container_of(node, struct lttng_session_trigger_list, + rcu_node)); +} + +static +void lttng_session_trigger_list_destroy(struct lttng_session_trigger_list *list) +{ + struct lttng_trigger_list_element *trigger_list_element, *tmp; + + /* Empty the list element by element, and then free the list itself. */ + cds_list_for_each_entry_safe(trigger_list_element, tmp, + &list->list, node) { + cds_list_del(&trigger_list_element->node); + free(trigger_list_element); + } + rcu_read_lock(); + /* Unpublish the list from the session_triggers_ht. */ + cds_lfht_del(list->session_triggers_ht, + &list->session_triggers_ht_node); + rcu_read_unlock(); + call_rcu(&list->rcu_node, free_session_trigger_list_rcu); +} + +static +int lttng_session_trigger_list_add(struct lttng_session_trigger_list *list, + const struct lttng_trigger *trigger) +{ + int ret = 0; + struct lttng_trigger_list_element *new_element = + zmalloc(sizeof(*new_element)); + + if (!new_element) { + ret = -1; + goto end; + } + CDS_INIT_LIST_HEAD(&new_element->node); + new_element->trigger = trigger; + cds_list_add(&new_element->node, &list->list); +end: + return ret; +} + +static +bool trigger_applies_to_session(const struct lttng_trigger *trigger, + const char *session_name) +{ + bool applies = false; + const struct lttng_condition *condition; + + condition = lttng_trigger_get_const_condition(trigger); + switch (lttng_condition_get_type(condition)) { + case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING: + case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED: + { + enum lttng_condition_status condition_status; + const char *condition_session_name; + + condition_status = lttng_condition_session_rotation_get_session_name( + condition, &condition_session_name); + if (condition_status != LTTNG_CONDITION_STATUS_OK) { + ERR("[notification-thread] Failed to retrieve session rotation condition's session name"); + goto end; + } + + assert(condition_session_name); + applies = !strcmp(condition_session_name, session_name); + break; + } + default: + goto end; + } +end: + return applies; +} + +/* + * Allocate and initialize an lttng_session_trigger_list which contains + * all triggers that apply to the session named 'session_name'. + * + * No ownership of 'session_name' is assumed by the session trigger list. + * It is the caller's responsability to ensure the session name is alive + * for as long as this list is. + */ +static +struct lttng_session_trigger_list *lttng_session_trigger_list_build( + const struct notification_thread_state *state, + const char *session_name) +{ + int trigger_count = 0; + struct lttng_session_trigger_list *session_trigger_list = NULL; + struct lttng_trigger_ht_element *trigger_ht_element = NULL; + struct cds_lfht_iter iter; + + session_trigger_list = lttng_session_trigger_list_create(session_name, + state->session_triggers_ht); + + /* Add all triggers applying to the session named 'session_name'. */ + cds_lfht_for_each_entry(state->triggers_ht, &iter, trigger_ht_element, + node) { + int ret; + + if (!trigger_applies_to_session(trigger_ht_element->trigger, + session_name)) { + continue; + } + + ret = lttng_session_trigger_list_add(session_trigger_list, + trigger_ht_element->trigger); + if (ret) { + goto error; + } + + trigger_count++; + } + + DBG("[notification-thread] Found %i triggers that apply to newly created session", + trigger_count); + return session_trigger_list; +error: + lttng_session_trigger_list_destroy(session_trigger_list); + return NULL; } static @@ -930,6 +1635,7 @@ struct session_info *find_or_create_session_info( struct session_info *session = NULL; struct cds_lfht_node *node; struct cds_lfht_iter iter; + struct lttng_session_trigger_list *trigger_list; rcu_read_lock(); cds_lfht_lookup(state->sessions_ht, @@ -945,18 +1651,34 @@ struct session_info *find_or_create_session_info( sessions_ht_node); assert(session->uid == uid); assert(session->gid == gid); + session_info_get(session); goto end; } - session = session_info_create(name, uid, gid); + trigger_list = lttng_session_trigger_list_build(state, name); + if (!trigger_list) { + goto error; + } + + session = session_info_create(name, uid, gid, trigger_list, + state->sessions_ht); if (!session) { ERR("[notification-thread] Failed to allocation session info for session \"%s\" (uid = %i, gid = %i)", name, uid, gid); - goto end; + lttng_session_trigger_list_destroy(trigger_list); + goto error; } + trigger_list = NULL; + + cds_lfht_add(state->sessions_ht, hash_key_str(name, lttng_ht_seed), + &session->sessions_ht_node); end: rcu_read_unlock(); return session; +error: + rcu_read_unlock(); + session_info_put(session); + return NULL; } static @@ -988,7 +1710,7 @@ int handle_notification_thread_command_add_channel( session_info = find_or_create_session_info(state, session_name, session_uid, session_gid); if (!session_info) { - /* Allocation error or an internal error occured. */ + /* Allocation error or an internal error occurred. */ goto error; } @@ -998,6 +1720,7 @@ int handle_notification_thread_command_add_channel( goto error; } + rcu_read_lock(); /* Build a list of all triggers applying to the new channel. */ cds_lfht_for_each_entry(state->triggers_ht, &iter, trigger_ht_element, node) { @@ -1010,6 +1733,7 @@ int handle_notification_thread_command_add_channel( new_element = zmalloc(sizeof(*new_element)); if (!new_element) { + rcu_read_unlock(); goto error; } CDS_INIT_LIST_HEAD(&new_element->node); @@ -1017,6 +1741,7 @@ int handle_notification_thread_command_add_channel( cds_list_add(&new_element->node, &trigger_list); trigger_count++; } + rcu_read_unlock(); DBG("[notification-thread] Found %i triggers that apply to newly added channel", trigger_count); @@ -1042,6 +1767,7 @@ int handle_notification_thread_command_add_channel( hash_channel_key(&new_channel_info->key), &channel_trigger_list->channel_triggers_ht_node); rcu_read_unlock(); + session_info_put(session_info); *cmd_result = LTTNG_OK; return 0; error: @@ -1050,6 +1776,20 @@ error: return 1; } +static +void free_channel_trigger_list_rcu(struct rcu_head *node) +{ + free(caa_container_of(node, struct lttng_channel_trigger_list, + rcu_node)); +} + +static +void free_channel_state_sample_rcu(struct rcu_head *node) +{ + free(caa_container_of(node, struct channel_state_sample, + rcu_node)); +} + static int handle_notification_thread_command_remove_channel( struct notification_thread_state *state, @@ -1092,7 +1832,7 @@ int handle_notification_thread_command_remove_channel( free(trigger_list_element); } cds_lfht_del(state->channel_triggers_ht, node); - free(trigger_list); + call_rcu(&trigger_list->rcu_node, free_channel_trigger_list_rcu); /* Free sampled channel state. */ cds_lfht_lookup(state->channel_state_ht, @@ -1111,7 +1851,7 @@ int handle_notification_thread_command_remove_channel( channel_state_ht_node); cds_lfht_del(state->channel_state_ht, node); - free(sample); + call_rcu(&sample->rcu_node, free_channel_state_sample_rcu); } /* Remove the channel from the channels_ht and free it. */ @@ -1132,40 +1872,244 @@ end: return 0; } +static +int handle_notification_thread_command_session_rotation( + struct notification_thread_state *state, + enum notification_thread_command_type cmd_type, + const char *session_name, uid_t session_uid, gid_t session_gid, + uint64_t trace_archive_chunk_id, + struct lttng_trace_archive_location *location, + enum lttng_error_code *_cmd_result) +{ + int ret = 0; + enum lttng_error_code cmd_result = LTTNG_OK; + struct lttng_session_trigger_list *trigger_list; + struct lttng_trigger_list_element *trigger_list_element; + struct session_info *session_info; + + rcu_read_lock(); + + session_info = find_or_create_session_info(state, session_name, + session_uid, session_gid); + if (!session_info) { + /* Allocation error or an internal error occurred. */ + ret = -1; + cmd_result = LTTNG_ERR_NOMEM; + goto end; + } + + session_info->rotation.ongoing = + cmd_type == NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING; + session_info->rotation.id = trace_archive_chunk_id; + trigger_list = get_session_trigger_list(state, session_name); + if (!trigger_list) { + DBG("[notification-thread] No triggers applying to session \"%s\" found", + session_name); + goto end; + } + + cds_list_for_each_entry(trigger_list_element, &trigger_list->list, + node) { + const struct lttng_condition *condition; + const struct lttng_action *action; + const struct lttng_trigger *trigger; + struct notification_client_list *client_list; + struct lttng_evaluation *evaluation = NULL; + enum lttng_condition_type condition_type; + bool client_list_is_empty; + + trigger = trigger_list_element->trigger; + condition = lttng_trigger_get_const_condition(trigger); + assert(condition); + condition_type = lttng_condition_get_type(condition); + + if (condition_type == LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING && + cmd_type != NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING) { + continue; + } else if (condition_type == LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED && + cmd_type != NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED) { + continue; + } + + action = lttng_trigger_get_const_action(trigger); + + /* Notify actions are the only type currently supported. */ + assert(lttng_action_get_type_const(action) == + LTTNG_ACTION_TYPE_NOTIFY); + + client_list = get_client_list_from_condition(state, condition); + assert(client_list); + + pthread_mutex_lock(&client_list->lock); + client_list_is_empty = cds_list_empty(&client_list->list); + pthread_mutex_unlock(&client_list->lock); + if (client_list_is_empty) { + /* + * No clients interested in the evaluation's result, + * skip it. + */ + continue; + } + + if (cmd_type == NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING) { + evaluation = lttng_evaluation_session_rotation_ongoing_create( + trace_archive_chunk_id); + } else { + evaluation = lttng_evaluation_session_rotation_completed_create( + trace_archive_chunk_id, location); + } + + if (!evaluation) { + /* Internal error */ + ret = -1; + cmd_result = LTTNG_ERR_UNK; + goto put_list; + } + + /* Dispatch evaluation result to all clients. */ + ret = send_evaluation_to_clients(trigger_list_element->trigger, + evaluation, client_list, state, + session_info->uid, + session_info->gid); + lttng_evaluation_destroy(evaluation); +put_list: + notification_client_list_put(client_list); + if (caa_unlikely(ret)) { + break; + } + } +end: + session_info_put(session_info); + *_cmd_result = cmd_result; + rcu_read_unlock(); + return ret; +} + static int condition_is_supported(struct lttng_condition *condition) { int ret; - switch (lttng_condition_get_type(condition)) { - case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW: - case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH: - { - enum lttng_domain_type domain; + switch (lttng_condition_get_type(condition)) { + case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW: + case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH: + { + enum lttng_domain_type domain; + + ret = lttng_condition_buffer_usage_get_domain_type(condition, + &domain); + if (ret) { + ret = -1; + goto end; + } + + if (domain != LTTNG_DOMAIN_KERNEL) { + ret = 1; + goto end; + } + + /* + * Older kernel tracers don't expose the API to monitor their + * buffers. Therefore, we reject triggers that require that + * mechanism to be available to be evaluated. + */ + ret = kernel_supports_ring_buffer_snapshot_sample_positions(); + break; + } + default: + ret = 1; + } +end: + return ret; +} + +/* Must be called with RCU read lock held. */ +static +int bind_trigger_to_matching_session(const struct lttng_trigger *trigger, + struct notification_thread_state *state) +{ + int ret = 0; + const struct lttng_condition *condition; + const char *session_name; + struct lttng_session_trigger_list *trigger_list; + + condition = lttng_trigger_get_const_condition(trigger); + switch (lttng_condition_get_type(condition)) { + case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING: + case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED: + { + enum lttng_condition_status status; + + status = lttng_condition_session_rotation_get_session_name( + condition, &session_name); + if (status != LTTNG_CONDITION_STATUS_OK) { + ERR("[notification-thread] Failed to bind trigger to session: unable to get 'session_rotation' condition's session name"); + ret = -1; + goto end; + } + break; + } + default: + ret = -1; + goto end; + } + + trigger_list = get_session_trigger_list(state, session_name); + if (!trigger_list) { + DBG("[notification-thread] Unable to bind trigger applying to session \"%s\" as it is not yet known to the notification system", + session_name); + goto end; + + } + + DBG("[notification-thread] Newly registered trigger bound to session \"%s\"", + session_name); + ret = lttng_session_trigger_list_add(trigger_list, trigger); +end: + return ret; +} + +/* Must be called with RCU read lock held. */ +static +int bind_trigger_to_matching_channels(const struct lttng_trigger *trigger, + struct notification_thread_state *state) +{ + int ret = 0; + struct cds_lfht_node *node; + struct cds_lfht_iter iter; + struct channel_info *channel; + + cds_lfht_for_each_entry(state->channels_ht, &iter, channel, + channels_ht_node) { + struct lttng_trigger_list_element *trigger_list_element; + struct lttng_channel_trigger_list *trigger_list; + struct cds_lfht_iter lookup_iter; - ret = lttng_condition_buffer_usage_get_domain_type(condition, - &domain); - if (ret) { - ret = -1; - goto end; + if (!trigger_applies_to_channel(trigger, channel)) { + continue; } - if (domain != LTTNG_DOMAIN_KERNEL) { - ret = 1; + cds_lfht_lookup(state->channel_triggers_ht, + hash_channel_key(&channel->key), + match_channel_trigger_list, + &channel->key, + &lookup_iter); + node = cds_lfht_iter_get_node(&lookup_iter); + assert(node); + trigger_list = caa_container_of(node, + struct lttng_channel_trigger_list, + channel_triggers_ht_node); + + trigger_list_element = zmalloc(sizeof(*trigger_list_element)); + if (!trigger_list_element) { + ret = -1; goto end; } - - /* - * Older kernel tracers don't expose the API to monitor their - * buffers. Therefore, we reject triggers that require that - * mechanism to be available to be evaluated. - */ - ret = kernel_supports_ring_buffer_snapshot_sample_positions( - kernel_tracer_fd); - break; - } - default: - ret = 1; + CDS_INIT_LIST_HEAD(&trigger_list_element->node); + trigger_list_element->trigger = trigger; + cds_list_add(&trigger_list_element->node, &trigger_list->list); + DBG("[notification-thread] Newly registered trigger bound to channel \"%s\"", + channel->name); } end: return ret; @@ -1177,7 +2121,7 @@ end: * * The effects of this are benign since: * - The client will succeed in registering the trigger, as it is valid, - * - The trigger will, internally, be bound to the channel, + * - The trigger will, internally, be bound to the channel/session, * - The notifications will not be sent since the client's credentials * are checked against the channel at that moment. * @@ -1201,7 +2145,6 @@ int handle_notification_thread_command_register_trigger( struct notification_client_list_element *client_list_element, *tmp; struct cds_lfht_node *node; struct cds_lfht_iter iter; - struct channel_info *channel; bool free_trigger = true; rcu_read_lock(); @@ -1253,14 +2196,11 @@ int handle_notification_thread_command_register_trigger( * It is not skipped as this is the only action type currently * supported. */ - client_list = zmalloc(sizeof(*client_list)); + client_list = notification_client_list_create(trigger); if (!client_list) { ret = -1; goto error_free_ht_element; } - cds_lfht_node_init(&client_list->notification_trigger_ht_node); - CDS_INIT_LIST_HEAD(&client_list->list); - client_list->trigger = trigger; /* Build a list of clients to which this new trigger applies. */ cds_lfht_for_each_entry(state->client_socket_ht, &iter, client, @@ -1272,52 +2212,37 @@ int handle_notification_thread_command_register_trigger( client_list_element = zmalloc(sizeof(*client_list_element)); if (!client_list_element) { ret = -1; - goto error_free_client_list; + goto error_put_client_list; } CDS_INIT_LIST_HEAD(&client_list_element->node); client_list_element->client = client; cds_list_add(&client_list_element->node, &client_list->list); } - cds_lfht_add(state->notification_trigger_clients_ht, - lttng_condition_hash(condition), - &client_list->notification_trigger_ht_node); - - /* - * Add the trigger to list of triggers bound to the channels currently - * known. - */ - cds_lfht_for_each_entry(state->channels_ht, &iter, channel, - channels_ht_node) { - struct lttng_trigger_list_element *trigger_list_element; - struct lttng_channel_trigger_list *trigger_list; - - if (!trigger_applies_to_channel(trigger, channel)) { - continue; + switch (get_condition_binding_object(condition)) { + case LTTNG_OBJECT_TYPE_SESSION: + /* Add the trigger to the list if it matches a known session. */ + ret = bind_trigger_to_matching_session(trigger, state); + if (ret) { + goto error_put_client_list; } - - cds_lfht_lookup(state->channel_triggers_ht, - hash_channel_key(&channel->key), - match_channel_trigger_list, - &channel->key, - &iter); - node = cds_lfht_iter_get_node(&iter); - assert(node); - trigger_list = caa_container_of(node, - struct lttng_channel_trigger_list, - channel_triggers_ht_node); - - trigger_list_element = zmalloc(sizeof(*trigger_list_element)); - if (!trigger_list_element) { - ret = -1; - goto error_free_client_list; + break; + case LTTNG_OBJECT_TYPE_CHANNEL: + /* + * Add the trigger to list of triggers bound to the channels + * currently known. + */ + ret = bind_trigger_to_matching_channels(trigger, state); + if (ret) { + goto error_put_client_list; } - CDS_INIT_LIST_HEAD(&trigger_list_element->node); - trigger_list_element->trigger = trigger; - cds_list_add(&trigger_list_element->node, &trigger_list->list); - - /* A trigger can only apply to one channel. */ break; + case LTTNG_OBJECT_TYPE_NONE: + break; + default: + ERR("[notification-thread] Unknown object type on which to bind a newly registered trigger was encountered"); + ret = -1; + goto error_put_client_list; } /* @@ -1345,13 +2270,15 @@ int handle_notification_thread_command_register_trigger( * current state. Otherwise, the next evaluation cycle may only see * that the evaluations remain the same (true for samples n-1 and n) and * the client will never know that the condition has been met. + * + * No need to lock the list here as it has not been published yet. */ cds_list_for_each_entry_safe(client_list_element, tmp, &client_list->list, node) { ret = evaluate_condition_for_client(trigger, condition, client_list_element->client, state); if (ret) { - goto error_free_client_list; + goto error_put_client_list; } } @@ -1359,31 +2286,31 @@ int handle_notification_thread_command_register_trigger( * Client list ownership transferred to the * notification_trigger_clients_ht. */ + publish_notification_client_list(state, client_list); client_list = NULL; *cmd_result = LTTNG_OK; -error_free_client_list: - if (client_list) { - cds_list_for_each_entry_safe(client_list_element, tmp, - &client_list->list, node) { - free(client_list_element); - } - free(client_list); - } + +error_put_client_list: + notification_client_list_put(client_list); + error_free_ht_element: free(trigger_ht_element); error: if (free_trigger) { - struct lttng_action *action = lttng_trigger_get_action(trigger); - - lttng_condition_destroy(condition); - lttng_action_destroy(action); lttng_trigger_destroy(trigger); } rcu_read_unlock(); return ret; } +static +void free_lttng_trigger_ht_element_rcu(struct rcu_head *node) +{ + free(caa_container_of(node, struct lttng_trigger_ht_element, + rcu_node)); +} + static int handle_notification_thread_command_unregister_trigger( struct notification_thread_state *state, @@ -1391,14 +2318,12 @@ int handle_notification_thread_command_unregister_trigger( enum lttng_error_code *_cmd_reply) { struct cds_lfht_iter iter; - struct cds_lfht_node *node, *triggers_ht_node; + struct cds_lfht_node *triggers_ht_node; struct lttng_channel_trigger_list *trigger_list; struct notification_client_list *client_list; - struct notification_client_list_element *client_list_element, *tmp; struct lttng_trigger_ht_element *trigger_ht_element = NULL; struct lttng_condition *condition = lttng_trigger_get_condition( trigger); - struct lttng_action *action; enum lttng_error_code cmd_reply; rcu_read_lock(); @@ -1423,8 +2348,8 @@ int handle_notification_thread_command_unregister_trigger( cds_list_for_each_entry_safe(trigger_element, tmp, &trigger_list->list, node) { - struct lttng_condition *current_condition = - lttng_trigger_get_condition( + const struct lttng_condition *current_condition = + lttng_trigger_get_const_condition( trigger_element->trigger); assert(current_condition); @@ -1444,33 +2369,22 @@ int handle_notification_thread_command_unregister_trigger( * Remove and release the client list from * notification_trigger_clients_ht. */ - cds_lfht_lookup(state->notification_trigger_clients_ht, - lttng_condition_hash(condition), - match_client_list, - trigger, - &iter); - node = cds_lfht_iter_get_node(&iter); - assert(node); - client_list = caa_container_of(node, struct notification_client_list, - notification_trigger_ht_node); - cds_list_for_each_entry_safe(client_list_element, tmp, - &client_list->list, node) { - free(client_list_element); - } - cds_lfht_del(state->notification_trigger_clients_ht, node); - free(client_list); + client_list = get_client_list_from_condition(state, condition); + assert(client_list); + + /* Put new reference and the hashtable's reference. */ + notification_client_list_put(client_list); + notification_client_list_put(client_list); + client_list = NULL; /* Remove trigger from triggers_ht. */ trigger_ht_element = caa_container_of(triggers_ht_node, struct lttng_trigger_ht_element, node); cds_lfht_del(state->triggers_ht, triggers_ht_node); - condition = lttng_trigger_get_condition(trigger_ht_element->trigger); - lttng_condition_destroy(condition); - action = lttng_trigger_get_action(trigger_ht_element->trigger); - lttng_action_destroy(action); + /* Release the ownership of the trigger. */ lttng_trigger_destroy(trigger_ht_element->trigger); - free(trigger_ht_element); + call_rcu(&trigger_ht_element->rcu_node, free_lttng_trigger_ht_element_rcu); end: rcu_read_unlock(); if (_cmd_reply) { @@ -1489,9 +2403,9 @@ int handle_notification_thread_command( struct notification_thread_command *cmd; /* Read the event pipe to put it back into a quiescent state. */ - ret = read(lttng_pipe_get_readfd(handle->cmd_queue.event_pipe), &counter, + ret = lttng_read(lttng_pipe_get_readfd(handle->cmd_queue.event_pipe), &counter, sizeof(counter)); - if (ret == -1) { + if (ret != sizeof(counter)) { goto error; } @@ -1531,6 +2445,21 @@ int handle_notification_thread_command( cmd->parameters.remove_channel.domain, &cmd->reply_code); break; + case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING: + case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED: + DBG("[notification-thread] Received session rotation %s command", + cmd->type == NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING ? + "ongoing" : "completed"); + ret = handle_notification_thread_command_session_rotation( + state, + cmd->type, + cmd->parameters.session_rotation.session_name, + cmd->parameters.session_rotation.uid, + cmd->parameters.session_rotation.gid, + cmd->parameters.session_rotation.trace_archive_chunk_id, + cmd->parameters.session_rotation.location, + &cmd->reply_code); + break; case NOTIFICATION_COMMAND_TYPE_QUIT: DBG("[notification-thread] Received quit command"); cmd->reply_code = LTTNG_OK; @@ -1559,12 +2488,6 @@ error: return -1; } -static -unsigned long hash_client_socket(int socket) -{ - return hash_key_ulong((void *) (unsigned long) socket, lttng_ht_seed); -} - static int socket_set_non_blocking(int socket) { @@ -1588,11 +2511,14 @@ end: return ret; } +/* Client lock must be acquired by caller. */ static int client_reset_inbound_state(struct notification_client *client) { int ret; + ASSERT_LOCKED(client->lock); + ret = lttng_dynamic_buffer_set_size( &client->communication.inbound.buffer, 0); assert(!ret); @@ -1623,14 +2549,19 @@ int handle_notification_thread_client_connect( ret = -1; goto error; } + pthread_mutex_init(&client->lock, NULL); + client->id = state->next_notification_client_id++; CDS_INIT_LIST_HEAD(&client->condition_list); lttng_dynamic_buffer_init(&client->communication.inbound.buffer); lttng_dynamic_buffer_init(&client->communication.outbound.buffer); client->communication.inbound.expect_creds = true; + + pthread_mutex_lock(&client->lock); ret = client_reset_inbound_state(client); + pthread_mutex_unlock(&client->lock); if (ret) { ERR("[notification-thread] Failed to reset client communication's inbound state"); - ret = 0; + ret = 0; goto error; } @@ -1671,6 +2602,9 @@ int handle_notification_thread_client_connect( cds_lfht_add(state->client_socket_ht, hash_client_socket(client->socket), &client->client_socket_ht_node); + cds_lfht_add(state->client_id_ht, + hash_client_id(client->id), + &client->client_id_ht_node); rcu_read_unlock(); return ret; @@ -1679,9 +2613,44 @@ error: return ret; } -int handle_notification_thread_client_disconnect( - int client_socket, +/* RCU read-lock must be held by the caller. */ +/* Client lock must be held by the caller */ +static +int notification_thread_client_disconnect( + struct notification_client *client, struct notification_thread_state *state) +{ + int ret; + struct lttng_condition_list_element *condition_list_element, *tmp; + + /* Acquire the client lock to disable its communication atomically. */ + client->communication.active = false; + ret = lttng_poll_del(&state->events, client->socket); + if (ret) { + ERR("[notification-thread] Failed to remove client socket %d from poll set", + client->socket); + } + + cds_lfht_del(state->client_socket_ht, &client->client_socket_ht_node); + cds_lfht_del(state->client_id_ht, &client->client_id_ht_node); + + /* Release all conditions to which the client was subscribed. */ + cds_list_for_each_entry_safe(condition_list_element, tmp, + &client->condition_list, node) { + (void) notification_thread_client_unsubscribe(client, + condition_list_element->condition, state, NULL); + } + + /* + * Client no longer accessible to other threads (through the + * client lists). + */ + notification_client_destroy(client, state); + return ret; +} + +int handle_notification_thread_client_disconnect( + int client_socket, struct notification_thread_state *state) { int ret = 0; struct notification_client *client; @@ -1698,13 +2667,9 @@ int handle_notification_thread_client_disconnect( goto end; } - ret = lttng_poll_del(&state->events, client_socket); - if (ret) { - ERR("[notification-thread] Failed to remove client socket from poll set"); - } - cds_lfht_del(state->client_socket_ht, - &client->client_socket_ht_node); - notification_client_destroy(client, state); + pthread_mutex_lock(&client->lock); + ret = notification_thread_client_disconnect(client, state); + pthread_mutex_unlock(&client->lock); end: rcu_read_unlock(); return ret; @@ -1720,11 +2685,13 @@ int handle_notification_thread_client_disconnect_all( rcu_read_lock(); DBG("[notification-thread] Closing all client connections"); cds_lfht_for_each_entry(state->client_socket_ht, &iter, client, - client_socket_ht_node) { + client_socket_ht_node) { int ret; - ret = handle_notification_thread_client_disconnect( - client->socket, state); + pthread_mutex_lock(&client->lock); + ret = notification_thread_client_disconnect( + client, state); + pthread_mutex_unlock(&client->lock); if (ret) { error_encoutered = true; } @@ -1740,6 +2707,7 @@ int handle_notification_thread_trigger_unregister_all( struct cds_lfht_iter iter; struct lttng_trigger_ht_element *trigger_ht_element; + rcu_read_lock(); cds_lfht_for_each_entry(state->triggers_ht, &iter, trigger_ht_element, node) { int ret = handle_notification_thread_command_unregister_trigger( @@ -1748,9 +2716,11 @@ int handle_notification_thread_trigger_unregister_all( error_occurred = true; } } + rcu_read_unlock(); return error_occurred ? -1 : 0; } +/* Client lock must be acquired by caller. */ static int client_flush_outgoing_queue(struct notification_client *client, struct notification_thread_state *state) @@ -1758,6 +2728,8 @@ int client_flush_outgoing_queue(struct notification_client *client, ssize_t ret; size_t to_send_count; + ASSERT_LOCKED(client->lock); + assert(client->communication.outbound.buffer.size != 0); to_send_count = client->communication.outbound.buffer.size; DBG("[notification-thread] Flushing client (socket fd = %i) outgoing queue", @@ -1766,8 +2738,7 @@ int client_flush_outgoing_queue(struct notification_client *client, ret = lttcomm_send_unix_sock_non_block(client->socket, client->communication.outbound.buffer.data, to_send_count); - if ((ret < 0 && (errno == EAGAIN || errno == EWOULDBLOCK)) || - (ret > 0 && ret < to_send_count)) { + if ((ret >= 0 && ret < to_send_count)) { DBG("[notification-thread] Client (socket fd = %i) outgoing queue could not be completely flushed", client->socket); to_send_count -= max(ret, 0); @@ -1796,8 +2767,7 @@ int client_flush_outgoing_queue(struct notification_client *client, /* Generic error, disconnect the client. */ ERR("[notification-thread] Failed to send flush outgoing queue, disconnecting client (socket fd = %i)", client->socket); - ret = handle_notification_thread_client_disconnect( - client->socket, state); + ret = notification_thread_client_disconnect(client, state); if (ret) { goto error; } @@ -1814,60 +2784,251 @@ int client_flush_outgoing_queue(struct notification_client *client, goto error; } - client->communication.outbound.queued_command_reply = false; - client->communication.outbound.dropped_notification = false; + client->communication.outbound.queued_command_reply = false; + client->communication.outbound.dropped_notification = false; + } + + return 0; +error: + return -1; +} + +/* Client lock must be acquired by caller. */ +static +int client_send_command_reply(struct notification_client *client, + struct notification_thread_state *state, + enum lttng_notification_channel_status status) +{ + int ret; + struct lttng_notification_channel_command_reply reply = { + .status = (int8_t) status, + }; + struct lttng_notification_channel_message msg = { + .type = (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_COMMAND_REPLY, + .size = sizeof(reply), + }; + char buffer[sizeof(msg) + sizeof(reply)]; + + ASSERT_LOCKED(client->lock); + + if (client->communication.outbound.queued_command_reply) { + /* Protocol error. */ + goto error; + } + + memcpy(buffer, &msg, sizeof(msg)); + memcpy(buffer + sizeof(msg), &reply, sizeof(reply)); + DBG("[notification-thread] Send command reply (%i)", (int) status); + + /* Enqueue buffer to outgoing queue and flush it. */ + ret = lttng_dynamic_buffer_append( + &client->communication.outbound.buffer, + buffer, sizeof(buffer)); + if (ret) { + goto error; + } + + ret = client_flush_outgoing_queue(client, state); + if (ret) { + goto error; + } + + if (client->communication.outbound.buffer.size != 0) { + /* Queue could not be emptied. */ + client->communication.outbound.queued_command_reply = true; + } + + return 0; +error: + return -1; +} + +static +int client_handle_message_unknown(struct notification_client *client, + struct notification_thread_state *state) +{ + int ret; + + pthread_mutex_lock(&client->lock); + + /* + * Receiving message header. The function will be called again + * once the rest of the message as been received and can be + * interpreted. + */ + const struct lttng_notification_channel_message *msg; + + assert(sizeof(*msg) == client->communication.inbound.buffer.size); + msg = (const struct lttng_notification_channel_message *) + client->communication.inbound.buffer.data; + + if (msg->size == 0 || + msg->size > DEFAULT_MAX_NOTIFICATION_CLIENT_MESSAGE_PAYLOAD_SIZE) { + ERR("[notification-thread] Invalid notification channel message: length = %u", + msg->size); + ret = -1; + goto end; + } + + switch (msg->type) { + case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE: + case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE: + case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE: + break; + default: + ret = -1; + ERR("[notification-thread] Invalid notification channel message: unexpected message type"); + goto end; + } + + client->communication.inbound.bytes_to_receive = msg->size; + client->communication.inbound.msg_type = + (enum lttng_notification_channel_message_type) msg->type; + ret = lttng_dynamic_buffer_set_size( + &client->communication.inbound.buffer, msg->size); +end: + pthread_mutex_unlock(&client->lock); + return ret; +} + +static +int client_handle_message_handshake(struct notification_client *client, + struct notification_thread_state *state) +{ + int ret; + struct lttng_notification_channel_command_handshake *handshake_client; + const struct lttng_notification_channel_command_handshake handshake_reply = { + .major = LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR, + .minor = LTTNG_NOTIFICATION_CHANNEL_VERSION_MINOR, + }; + const struct lttng_notification_channel_message msg_header = { + .type = LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE, + .size = sizeof(handshake_reply), + }; + enum lttng_notification_channel_status status = + LTTNG_NOTIFICATION_CHANNEL_STATUS_OK; + char send_buffer[sizeof(msg_header) + sizeof(handshake_reply)]; + + pthread_mutex_lock(&client->lock); + + memcpy(send_buffer, &msg_header, sizeof(msg_header)); + memcpy(send_buffer + sizeof(msg_header), &handshake_reply, + sizeof(handshake_reply)); + + handshake_client = + (struct lttng_notification_channel_command_handshake *) + client->communication.inbound.buffer + .data; + client->major = handshake_client->major; + client->minor = handshake_client->minor; + if (!client->communication.inbound.creds_received) { + ERR("[notification-thread] No credentials received from client"); + ret = -1; + goto end; + } + + client->uid = LTTNG_SOCK_GET_UID_CRED( + &client->communication.inbound.creds); + client->gid = LTTNG_SOCK_GET_GID_CRED( + &client->communication.inbound.creds); + DBG("[notification-thread] Received handshake from client (uid = %u, gid = %u) with version %i.%i", + client->uid, client->gid, (int) client->major, + (int) client->minor); + + if (handshake_client->major != + LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR) { + status = LTTNG_NOTIFICATION_CHANNEL_STATUS_UNSUPPORTED_VERSION; } - return 0; -error: - return -1; + ret = lttng_dynamic_buffer_append( + &client->communication.outbound.buffer, send_buffer, + sizeof(send_buffer)); + if (ret) { + ERR("[notification-thread] Failed to send protocol version to notification channel client"); + goto end; + } + + client->validated = true; + client->communication.active = true; + + ret = client_flush_outgoing_queue(client, state); + if (ret) { + goto end; + } + + ret = client_send_command_reply(client, state, status); + if (ret) { + ERR("[notification-thread] Failed to send reply to notification channel client"); + goto end; + } + + /* Set reception state to receive the next message header. */ + ret = client_reset_inbound_state(client); + if (ret) { + ERR("[notification-thread] Failed to reset client communication's inbound state"); + goto end; + } + +end: + pthread_mutex_unlock(&client->lock); + return ret; } static -int client_send_command_reply(struct notification_client *client, - struct notification_thread_state *state, - enum lttng_notification_channel_status status) +int client_handle_message_subscription( + struct notification_client *client, + enum lttng_notification_channel_message_type msg_type, + struct notification_thread_state *state) { int ret; - struct lttng_notification_channel_command_reply reply = { - .status = (int8_t) status, - }; - struct lttng_notification_channel_message msg = { - .type = (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_COMMAND_REPLY, - .size = sizeof(reply), - }; - char buffer[sizeof(msg) + sizeof(reply)]; + struct lttng_condition *condition; + enum lttng_notification_channel_status status = + LTTNG_NOTIFICATION_CHANNEL_STATUS_OK; + struct lttng_payload_view condition_view = + lttng_payload_view_from_dynamic_buffer( + &client->communication.inbound.buffer, + 0, -1); + size_t expected_condition_size; - if (client->communication.outbound.queued_command_reply) { - /* Protocol error. */ - goto error; - } + pthread_mutex_lock(&client->lock); + expected_condition_size = client->communication.inbound.buffer.size; + pthread_mutex_unlock(&client->lock); - memcpy(buffer, &msg, sizeof(msg)); - memcpy(buffer + sizeof(msg), &reply, sizeof(reply)); - DBG("[notification-thread] Send command reply (%i)", (int) status); + ret = lttng_condition_create_from_payload(&condition_view, &condition); + if (ret != expected_condition_size) { + ERR("[notification-thread] Malformed condition received from client"); + goto end; + } - /* Enqueue buffer to outgoing queue and flush it. */ - ret = lttng_dynamic_buffer_append( - &client->communication.outbound.buffer, - buffer, sizeof(buffer)); + if (msg_type == LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE) { + ret = notification_thread_client_subscribe( + client, condition, state, &status); + } else { + ret = notification_thread_client_unsubscribe( + client, condition, state, &status); + } if (ret) { - goto error; + goto end; } - ret = client_flush_outgoing_queue(client, state); + pthread_mutex_lock(&client->lock); + ret = client_send_command_reply(client, state, status); if (ret) { - goto error; + ERR("[notification-thread] Failed to send reply to notification channel client"); + goto end_unlock; } - if (client->communication.outbound.buffer.size != 0) { - /* Queue could not be emptied. */ - client->communication.outbound.queued_command_reply = true; + /* Set reception state to receive the next message header. */ + ret = client_reset_inbound_state(client); + if (ret) { + ERR("[notification-thread] Failed to reset client communication's inbound state"); + goto end_unlock; } - return 0; -error: - return -1; +end_unlock: + pthread_mutex_unlock(&client->lock); +end: + return ret; } static @@ -1889,158 +3050,19 @@ int client_dispatch_message(struct notification_client *client, switch (client->communication.inbound.msg_type) { case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN: { - /* - * Receiving message header. The function will be called again - * once the rest of the message as been received and can be - * interpreted. - */ - const struct lttng_notification_channel_message *msg; - - assert(sizeof(*msg) == - client->communication.inbound.buffer.size); - msg = (const struct lttng_notification_channel_message *) - client->communication.inbound.buffer.data; - - if (msg->size == 0 || msg->size > DEFAULT_MAX_NOTIFICATION_CLIENT_MESSAGE_PAYLOAD_SIZE) { - ERR("[notification-thread] Invalid notification channel message: length = %u", msg->size); - ret = -1; - goto end; - } - - switch (msg->type) { - case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE: - case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE: - case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE: - break; - default: - ret = -1; - ERR("[notification-thread] Invalid notification channel message: unexpected message type"); - goto end; - } - - client->communication.inbound.bytes_to_receive = msg->size; - client->communication.inbound.msg_type = - (enum lttng_notification_channel_message_type) msg->type; - ret = lttng_dynamic_buffer_set_size( - &client->communication.inbound.buffer, msg->size); - if (ret) { - goto end; - } + ret = client_handle_message_unknown(client, state); break; } case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE: { - struct lttng_notification_channel_command_handshake *handshake_client; - struct lttng_notification_channel_command_handshake handshake_reply = { - .major = LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR, - .minor = LTTNG_NOTIFICATION_CHANNEL_VERSION_MINOR, - }; - struct lttng_notification_channel_message msg_header = { - .type = LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE, - .size = sizeof(handshake_reply), - }; - enum lttng_notification_channel_status status = - LTTNG_NOTIFICATION_CHANNEL_STATUS_OK; - char send_buffer[sizeof(msg_header) + sizeof(handshake_reply)]; - - memcpy(send_buffer, &msg_header, sizeof(msg_header)); - memcpy(send_buffer + sizeof(msg_header), &handshake_reply, - sizeof(handshake_reply)); - - handshake_client = - (struct lttng_notification_channel_command_handshake *) - client->communication.inbound.buffer.data; - client->major = handshake_client->major; - client->minor = handshake_client->minor; - if (!client->communication.inbound.creds_received) { - ERR("[notification-thread] No credentials received from client"); - ret = -1; - goto end; - } - - client->uid = LTTNG_SOCK_GET_UID_CRED( - &client->communication.inbound.creds); - client->gid = LTTNG_SOCK_GET_GID_CRED( - &client->communication.inbound.creds); - DBG("[notification-thread] Received handshake from client (uid = %u, gid = %u) with version %i.%i", - client->uid, client->gid, (int) client->major, - (int) client->minor); - - if (handshake_client->major != LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR) { - status = LTTNG_NOTIFICATION_CHANNEL_STATUS_UNSUPPORTED_VERSION; - } - - ret = lttng_dynamic_buffer_append(&client->communication.outbound.buffer, - send_buffer, sizeof(send_buffer)); - if (ret) { - ERR("[notification-thread] Failed to send protocol version to notification channel client"); - goto end; - } - - ret = client_flush_outgoing_queue(client, state); - if (ret) { - goto end; - } - - ret = client_send_command_reply(client, state, status); - if (ret) { - ERR("[notification-thread] Failed to send reply to notification channel client"); - goto end; - } - - /* Set reception state to receive the next message header. */ - ret = client_reset_inbound_state(client); - if (ret) { - ERR("[notification-thread] Failed to reset client communication's inbound state"); - goto end; - } - client->validated = true; + ret = client_handle_message_handshake(client, state); break; } case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE: case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE: { - struct lttng_condition *condition; - enum lttng_notification_channel_status status = - LTTNG_NOTIFICATION_CHANNEL_STATUS_OK; - const struct lttng_buffer_view condition_view = - lttng_buffer_view_from_dynamic_buffer( - &client->communication.inbound.buffer, - 0, -1); - size_t expected_condition_size = - client->communication.inbound.buffer.size; - - ret = lttng_condition_create_from_buffer(&condition_view, - &condition); - if (ret != expected_condition_size) { - ERR("[notification-thread] Malformed condition received from client"); - goto end; - } - - if (client->communication.inbound.msg_type == - LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE) { - ret = notification_thread_client_subscribe(client, - condition, state, &status); - } else { - ret = notification_thread_client_unsubscribe(client, - condition, state, &status); - } - if (ret) { - goto end; - } - - ret = client_send_command_reply(client, state, status); - if (ret) { - ERR("[notification-thread] Failed to send reply to notification channel client"); - goto end; - } - - /* Set reception state to receive the next message header. */ - ret = client_reset_inbound_state(client); - if (ret) { - ERR("[notification-thread] Failed to reset client communication's inbound state"); - goto end; - } + ret = client_handle_message_subscription(client, + client->communication.inbound.msg_type, state); break; } default: @@ -2058,6 +3080,7 @@ int handle_notification_thread_client_in( struct notification_client *client; ssize_t recv_ret; size_t offset; + bool message_is_complete = false; client = get_client_from_socket(socket, state); if (!client) { @@ -2066,6 +3089,7 @@ int handle_notification_thread_client_in( goto end; } + pthread_mutex_lock(&client->lock); offset = client->communication.inbound.buffer.size - client->communication.inbound.bytes_to_receive; if (client->communication.inbound.expect_creds) { @@ -2082,12 +3106,17 @@ int handle_notification_thread_client_in( client->communication.inbound.buffer.data + offset, client->communication.inbound.bytes_to_receive); } + if (recv_ret >= 0) { + client->communication.inbound.bytes_to_receive -= recv_ret; + message_is_complete = client->communication.inbound + .bytes_to_receive == 0; + } + pthread_mutex_unlock(&client->lock); if (recv_ret < 0) { goto error_disconnect_client; } - client->communication.inbound.bytes_to_receive -= recv_ret; - if (client->communication.inbound.bytes_to_receive == 0) { + if (message_is_complete) { ret = client_dispatch_message(client, state); if (ret) { /* @@ -2096,13 +3125,13 @@ int handle_notification_thread_client_in( */ goto error_disconnect_client; } - } else { - goto end; } end: return ret; error_disconnect_client: - ret = handle_notification_thread_client_disconnect(socket, state); + pthread_mutex_lock(&client->lock); + ret = notification_thread_client_disconnect(client, state); + pthread_mutex_unlock(&client->lock); return ret; } @@ -2120,7 +3149,9 @@ int handle_notification_thread_client_out( goto end; } + pthread_mutex_lock(&client->lock); ret = client_flush_outgoing_queue(client, state); + pthread_mutex_unlock(&client->lock); if (ret) { goto end; } @@ -2129,20 +3160,17 @@ end: } static -bool evaluate_buffer_usage_condition(struct lttng_condition *condition, - struct channel_state_sample *sample, uint64_t buffer_capacity) +bool evaluate_buffer_usage_condition(const struct lttng_condition *condition, + const struct channel_state_sample *sample, + uint64_t buffer_capacity) { bool result = false; uint64_t threshold; enum lttng_condition_type condition_type; - struct lttng_condition_buffer_usage *use_condition = container_of( + const struct lttng_condition_buffer_usage *use_condition = container_of( condition, struct lttng_condition_buffer_usage, parent); - if (!sample) { - goto end; - } - if (use_condition->threshold_bytes.set) { threshold = use_condition->threshold_bytes.value; } else { @@ -2154,7 +3182,7 @@ bool evaluate_buffer_usage_condition(struct lttng_condition *condition, * forego this double-multiplication or it could be performed * as fixed-point math. * - * Note that caching should accomodate the case where the + * Note that caching should accommodates the case where the * condition applies to multiple channels (i.e. don't assume * that all channels matching my_chann* have the same size...) */ @@ -2186,32 +3214,73 @@ bool evaluate_buffer_usage_condition(struct lttng_condition *condition, result = true; } } -end: + return result; } static -int evaluate_condition(struct lttng_condition *condition, +bool evaluate_session_consumed_size_condition( + const struct lttng_condition *condition, + uint64_t session_consumed_size) +{ + uint64_t threshold; + const struct lttng_condition_session_consumed_size *size_condition = + container_of(condition, + struct lttng_condition_session_consumed_size, + parent); + + threshold = size_condition->consumed_threshold_bytes.value; + DBG("[notification-thread] Session consumed size condition being evaluated: threshold = %" PRIu64 ", current size = %" PRIu64, + threshold, session_consumed_size); + return session_consumed_size >= threshold; +} + +static +int evaluate_buffer_condition(const struct lttng_condition *condition, struct lttng_evaluation **evaluation, - struct notification_thread_state *state, - struct channel_state_sample *previous_sample, - struct channel_state_sample *latest_sample, - uint64_t buffer_capacity) + const struct notification_thread_state *state, + const struct channel_state_sample *previous_sample, + const struct channel_state_sample *latest_sample, + uint64_t previous_session_consumed_total, + uint64_t latest_session_consumed_total, + struct channel_info *channel_info) { int ret = 0; enum lttng_condition_type condition_type; - bool previous_sample_result; + const bool previous_sample_available = !!previous_sample; + bool previous_sample_result = false; bool latest_sample_result; condition_type = lttng_condition_get_type(condition); - /* No other condition type supported for the moment. */ - assert(condition_type == LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW || - condition_type == LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH); - previous_sample_result = evaluate_buffer_usage_condition(condition, - previous_sample, buffer_capacity); - latest_sample_result = evaluate_buffer_usage_condition(condition, - latest_sample, buffer_capacity); + switch (condition_type) { + case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW: + case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH: + if (caa_likely(previous_sample_available)) { + previous_sample_result = + evaluate_buffer_usage_condition(condition, + previous_sample, channel_info->capacity); + } + latest_sample_result = evaluate_buffer_usage_condition( + condition, latest_sample, + channel_info->capacity); + break; + case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE: + if (caa_likely(previous_sample_available)) { + previous_sample_result = + evaluate_session_consumed_size_condition( + condition, + previous_session_consumed_total); + } + latest_sample_result = + evaluate_session_consumed_size_condition( + condition, + latest_session_consumed_total); + break; + default: + /* Unknown condition type; internal error. */ + abort(); + } if (!latest_sample_result || (previous_sample_result == latest_sample_result)) { @@ -2224,23 +3293,36 @@ int evaluate_condition(struct lttng_condition *condition, goto end; } - if (evaluation && latest_sample_result) { + if (!evaluation || !latest_sample_result) { + goto end; + } + + switch (condition_type) { + case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW: + case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH: *evaluation = lttng_evaluation_buffer_usage_create( condition_type, latest_sample->highest_usage, - buffer_capacity); - if (!*evaluation) { - ret = -1; - goto end; - } + channel_info->capacity); + break; + case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE: + *evaluation = lttng_evaluation_session_consumed_size_create( + latest_session_consumed_total); + break; + default: + abort(); + } + + if (!*evaluation) { + ret = -1; + goto end; } end: return ret; } static -int client_enqueue_dropped_notification(struct notification_client *client, - struct notification_thread_state *state) +int client_enqueue_dropped_notification(struct notification_client *client) { int ret; struct lttng_notification_channel_message msg = { @@ -2248,81 +3330,108 @@ int client_enqueue_dropped_notification(struct notification_client *client, .size = 0, }; + ASSERT_LOCKED(client->lock); + ret = lttng_dynamic_buffer_append( &client->communication.outbound.buffer, &msg, sizeof(msg)); return ret; } +/* + * Permission checks relative to notification channel clients are performed + * here. Notice how object, client, and trigger credentials are involved in + * this check. + * + * The `object` credentials are the credentials associated with the "subject" + * of a condition. For instance, a `rotation completed` condition applies + * to a session. When that condition is met, it will produce an evaluation + * against a session. Hence, in this case, the `object` credentials are the + * credentials of the "subject" session. + * + * The `trigger` credentials are the credentials of the user that registered the + * trigger. + * + * The `client` credentials are the credentials of the user that created a given + * notification channel. + * + * In terms of visibility, it is expected that non-privilieged users can only + * register triggers against "their" objects (their own sessions and + * applications they are allowed to interact with). They can then open a + * notification channel and subscribe to notifications associated with those + * triggers. + * + * As for privilieged users, they can register triggers against the objects of + * other users. They can then subscribe to the notifications associated to their + * triggers. Privilieged users _can't_ subscribe to the notifications of + * triggers owned by other users; they must create their own triggers. + * + * This is more a concern of usability than security. It would be difficult for + * a root user reliably subscribe to a specific set of conditions without + * interference from external users (those could, for instance, unregister + * their triggers). + */ static -int send_evaluation_to_clients(struct lttng_trigger *trigger, - struct lttng_evaluation *evaluation, +int send_evaluation_to_clients(const struct lttng_trigger *trigger, + const struct lttng_evaluation *evaluation, struct notification_client_list* client_list, struct notification_thread_state *state, - uid_t channel_uid, gid_t channel_gid) + uid_t object_uid, gid_t object_gid) { int ret = 0; - struct lttng_dynamic_buffer msg_buffer; + struct lttng_payload msg_payload; struct notification_client_list_element *client_list_element, *tmp; - struct lttng_notification *notification; - struct lttng_condition *condition; - ssize_t expected_notification_size, notification_size; - struct lttng_notification_channel_message msg; - - lttng_dynamic_buffer_init(&msg_buffer); - - condition = lttng_trigger_get_condition(trigger); - assert(condition); - - notification = lttng_notification_create(condition, evaluation); - if (!notification) { - ret = -1; - goto end; - } + const struct lttng_notification notification = { + .condition = (struct lttng_condition *) lttng_trigger_get_const_condition(trigger), + .evaluation = (struct lttng_evaluation *) evaluation, + }; + struct lttng_notification_channel_message msg_header = { + .type = (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION, + }; + const struct lttng_credentials *trigger_creds = lttng_trigger_get_credentials(trigger); - expected_notification_size = lttng_notification_serialize(notification, - NULL); - if (expected_notification_size < 0) { - ERR("[notification-thread] Failed to get size of serialized notification"); - ret = -1; - goto end; - } + lttng_payload_init(&msg_payload); - msg.type = (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION; - msg.size = (uint32_t) expected_notification_size; - ret = lttng_dynamic_buffer_append(&msg_buffer, &msg, sizeof(msg)); + ret = lttng_dynamic_buffer_append(&msg_payload.buffer, &msg_header, + sizeof(msg_header)); if (ret) { goto end; } - ret = lttng_dynamic_buffer_set_size(&msg_buffer, - msg_buffer.size + expected_notification_size); + ret = lttng_notification_serialize(¬ification, &msg_payload); if (ret) { - goto end; - } - - notification_size = lttng_notification_serialize(notification, - msg_buffer.data + sizeof(msg)); - if (notification_size != expected_notification_size) { ERR("[notification-thread] Failed to serialize notification"); ret = -1; goto end; } + /* Update payload size. */ + ((struct lttng_notification_channel_message *) msg_payload.buffer.data) + ->size = (uint32_t)( + msg_payload.buffer.size - sizeof(msg_header)); + + pthread_mutex_lock(&client_list->lock); cds_list_for_each_entry_safe(client_list_element, tmp, &client_list->list, node) { struct notification_client *client = client_list_element->client; - if (client->uid != channel_uid && client->gid != channel_gid && + ret = 0; + pthread_mutex_lock(&client->lock); + if (client->uid != object_uid && client->gid != object_gid && client->uid != 0) { /* Client is not allowed to monitor this channel. */ - DBG("[notification-thread] Skipping client at it does not have the permission to receive notification for this channel"); - continue; + DBG("[notification-thread] Skipping client at it does not have the object permission to receive notification for this trigger"); + goto unlock_client; + } + + if (client->uid != trigger_creds->uid && client->gid != trigger_creds->gid) { + DBG("[notification-thread] Skipping client at it does not have the permission to receive notification for this trigger"); + goto unlock_client; } DBG("[notification-thread] Sending notification to client (fd = %i, %zu bytes)", - client->socket, msg_buffer.size); + client->socket, msg_payload.buffer.size); if (client->communication.outbound.buffer.size) { /* * Outgoing data is already buffered for this client; @@ -2336,30 +3445,37 @@ int send_evaluation_to_clients(struct lttng_trigger *trigger, if (!client->communication.outbound.dropped_notification) { client->communication.outbound.dropped_notification = true; ret = client_enqueue_dropped_notification( - client, state); + client); if (ret) { - goto end; + goto unlock_client; } } - continue; + goto unlock_client; } ret = lttng_dynamic_buffer_append_buffer( &client->communication.outbound.buffer, - &msg_buffer); + &msg_payload.buffer); if (ret) { - goto end; + goto unlock_client; } ret = client_flush_outgoing_queue(client, state); if (ret) { - goto end; + goto unlock_client; + } +unlock_client: + pthread_mutex_unlock(&client->lock); + if (ret) { + goto end_unlock_list; } } ret = 0; + +end_unlock_list: + pthread_mutex_unlock(&client_list->lock); end: - lttng_notification_destroy(notification); - lttng_dynamic_buffer_reset(&msg_buffer); + lttng_payload_reset(&msg_payload); return ret; } @@ -2369,13 +3485,14 @@ int handle_notification_thread_channel_sample( { int ret = 0; struct lttcomm_consumer_channel_monitor_msg sample_msg; - struct channel_state_sample previous_sample, latest_sample; struct channel_info *channel_info; struct cds_lfht_node *node; struct cds_lfht_iter iter; struct lttng_channel_trigger_list *trigger_list; struct lttng_trigger_list_element *trigger_list_element; bool previous_sample_available = false; + struct channel_state_sample previous_sample, latest_sample; + uint64_t previous_session_consumed_total, latest_session_consumed_total; /* * The monitoring pipe only holds messages smaller than PIPE_BUF, @@ -2394,6 +3511,7 @@ int handle_notification_thread_channel_sample( latest_sample.key.domain = domain; latest_sample.highest_usage = sample_msg.highest; latest_sample.lowest_usage = sample_msg.lowest; + latest_sample.channel_total_consumed = sample_msg.total_consumed; rcu_read_lock(); @@ -2404,7 +3522,7 @@ int handle_notification_thread_channel_sample( &latest_sample.key, &iter); node = cds_lfht_iter_get_node(&iter); - if (!node) { + if (caa_unlikely(!node)) { /* * Not an error since the consumer can push a sample to the pipe * and the rest of the session daemon could notify us of the @@ -2419,12 +3537,16 @@ int handle_notification_thread_channel_sample( } channel_info = caa_container_of(node, struct channel_info, channels_ht_node); - DBG("[notification-thread] Handling channel sample for channel %s (key = %" PRIu64 ") in session %s (highest usage = %" PRIu64 ", lowest usage = %" PRIu64")", + DBG("[notification-thread] Handling channel sample for channel %s (key = %" PRIu64 ") in session %s (highest usage = %" PRIu64 ", lowest usage = %" PRIu64", total consumed = %" PRIu64")", channel_info->name, latest_sample.key.key, channel_info->session_info->name, latest_sample.highest_usage, - latest_sample.lowest_usage); + latest_sample.lowest_usage, + latest_sample.channel_total_consumed); + + previous_session_consumed_total = + channel_info->session_info->consumed_data_size; /* Retrieve the channel's last sample, if it exists, and update it. */ cds_lfht_lookup(state->channel_state_ht, @@ -2433,18 +3555,24 @@ int handle_notification_thread_channel_sample( &latest_sample.key, &iter); node = cds_lfht_iter_get_node(&iter); - if (node) { + if (caa_likely(node)) { struct channel_state_sample *stored_sample; /* Update the sample stored. */ stored_sample = caa_container_of(node, struct channel_state_sample, channel_state_ht_node); + memcpy(&previous_sample, stored_sample, sizeof(previous_sample)); stored_sample->highest_usage = latest_sample.highest_usage; stored_sample->lowest_usage = latest_sample.lowest_usage; + stored_sample->channel_total_consumed = latest_sample.channel_total_consumed; previous_sample_available = true; + + latest_session_consumed_total = + previous_session_consumed_total + + (latest_sample.channel_total_consumed - previous_sample.channel_total_consumed); } else { /* * This is the channel's first sample, allocate space for and @@ -2463,8 +3591,15 @@ int handle_notification_thread_channel_sample( cds_lfht_add(state->channel_state_ht, hash_channel_key(&stored_sample->key), &stored_sample->channel_state_ht_node); + + latest_session_consumed_total = + previous_session_consumed_total + + latest_sample.channel_total_consumed; } + channel_info->session_info->consumed_data_size = + latest_session_consumed_total; + /* Find triggers associated with this channel. */ cds_lfht_lookup(state->channel_triggers_ht, hash_channel_key(&latest_sample.key), @@ -2472,61 +3607,58 @@ int handle_notification_thread_channel_sample( &latest_sample.key, &iter); node = cds_lfht_iter_get_node(&iter); - if (!node) { + if (caa_likely(!node)) { goto end_unlock; } trigger_list = caa_container_of(node, struct lttng_channel_trigger_list, channel_triggers_ht_node); cds_list_for_each_entry(trigger_list_element, &trigger_list->list, - node) { - struct lttng_condition *condition; - struct lttng_action *action; - struct lttng_trigger *trigger; - struct notification_client_list *client_list; + node) { + const struct lttng_condition *condition; + const struct lttng_action *action; + const struct lttng_trigger *trigger; + struct notification_client_list *client_list = NULL; struct lttng_evaluation *evaluation = NULL; + bool client_list_is_empty; + ret = 0; trigger = trigger_list_element->trigger; - condition = lttng_trigger_get_condition(trigger); + condition = lttng_trigger_get_const_condition(trigger); assert(condition); - action = lttng_trigger_get_action(trigger); + action = lttng_trigger_get_const_action(trigger); /* Notify actions are the only type currently supported. */ - assert(lttng_action_get_type(action) == + assert(lttng_action_get_type_const(action) == LTTNG_ACTION_TYPE_NOTIFY); /* * Check if any client is subscribed to the result of this * evaluation. */ - cds_lfht_lookup(state->notification_trigger_clients_ht, - lttng_condition_hash(condition), - match_client_list, - trigger, - &iter); - node = cds_lfht_iter_get_node(&iter); - assert(node); - - client_list = caa_container_of(node, - struct notification_client_list, - notification_trigger_ht_node); - if (cds_list_empty(&client_list->list)) { + client_list = get_client_list_from_condition(state, condition); + assert(client_list); + client_list_is_empty = cds_list_empty(&client_list->list); + if (client_list_is_empty) { /* * No clients interested in the evaluation's result, * skip it. */ - continue; + goto put_list; } - ret = evaluate_condition(condition, &evaluation, state, + ret = evaluate_buffer_condition(condition, &evaluation, state, previous_sample_available ? &previous_sample : NULL, - &latest_sample, channel_info->capacity); - if (ret) { - goto end_unlock; + &latest_sample, + previous_session_consumed_total, + latest_session_consumed_total, + channel_info); + if (caa_unlikely(ret)) { + goto put_list; } - if (!evaluation) { - continue; + if (caa_likely(!evaluation)) { + goto put_list; } /* Dispatch evaluation result to all clients. */ @@ -2535,8 +3667,10 @@ int handle_notification_thread_channel_sample( channel_info->session_info->uid, channel_info->session_info->gid); lttng_evaluation_destroy(evaluation); - if (ret) { - goto end_unlock; +put_list: + notification_client_list_put(client_list); + if (caa_unlikely(ret)) { + break; } } end_unlock: