From: Francis Deslauriers Date: Fri, 16 Apr 2021 15:14:21 +0000 (-0400) Subject: sessiond: refcount `ust_error_accounting_entry` X-Git-Tag: v2.13.0-rc1~16 X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=a5a212809b470aafd9c7f4cacbebfb4652feb16b;p=lttng-tools.git sessiond: refcount `ust_error_accounting_entry` Keep a reference count of the `ust_error_accounting_entry` to reclaim memory and cleanup handles as we go. Triggers on a sessiond target all applications regardless of the UID of both the trigger and the application. This means that whenever a new UST counter is created for a UID, we need to keep it around as long as there is 1. an application from that UID, or 2. an event notifier registered. This commit achieves that by keeping a count of the registered event notifiers. If the count is above zero, we keep a reference on every UID entries. When the count reaches zero, we put that reference on every entries. The event notifier count is guarded by a mutex since it's accessed by both the notification thread and UST registration thread. Here is the pseudo code for the relevant error accounting events: App registration: lookup entry for application UID in hashtable if found: get a reference on that existing entry else: create a new entry for that UID get a reference on that new entry if event_notifier_count > 0: get an extra reference on the behalf of the event notifiers Event notifier registration: increment event_notifier_count if event_notifier_count == 1: get a reference on all existing UID entries App unregistration: put reference on application UID entry Event notifier unregistration: decrement event_notifier_count if event_notifier_count == 0: put ref on all existing UID entries Signed-off-by: Francis Deslauriers Signed-off-by: Jérémie Galarneau Change-Id: I74667d30a5b6975bad7975b82f6819e263199cd0 --- diff --git a/src/bin/lttng-sessiond/event-notifier-error-accounting.c b/src/bin/lttng-sessiond/event-notifier-error-accounting.c index aac685467..70fa39e02 100644 --- a/src/bin/lttng-sessiond/event-notifier-error-accounting.c +++ b/src/bin/lttng-sessiond/event-notifier-error-accounting.c @@ -33,12 +33,13 @@ struct index_ht_entry { struct ust_error_accounting_entry { uid_t uid; + struct urcu_ref ref; struct lttng_ht_node_u64 node; struct rcu_head rcu_head; struct ustctl_daemon_counter *daemon_counter; /* - * Those `lttng_ust_abi_object_data` are anonymous handles to the counters - * objects. + * Those `lttng_ust_abi_object_data` are anonymous handles to the + * counters objects. * They are only used to be duplicated for each new applications of the * user. To destroy them, call with the `sock` parameter set to -1. * e.g. `ustctl_release_object(-1, data)`; @@ -49,10 +50,10 @@ struct ust_error_accounting_entry { }; struct kernel_error_accounting_entry { - int kernel_event_notifier_error_counter_fd; + int error_counter_fd; }; -static struct kernel_error_accounting_entry kernel_error_accountant; +static struct kernel_error_accounting_entry kernel_error_accounting_entry; /* Hashtable mapping uid to error_account_entry. */ static struct lttng_ht *error_counter_uid_ht; @@ -111,6 +112,106 @@ const char *error_accounting_status_str( } } +#ifdef HAVE_LIBLTTNG_UST_CTL +struct event_notifier_counter { + pthread_mutex_t lock; + long count; +}; + +static struct event_notifier_counter the_event_notifier_counter; + +static void free_ust_error_accounting_entry(struct rcu_head *head) +{ + int i; + struct ust_error_accounting_entry *entry = + caa_container_of(head, typeof(*entry), rcu_head); + + for (i = 0; i < entry->nr_counter_cpu_fds; i++) { + ustctl_release_object(-1, entry->cpu_counters[i]); + free(entry->cpu_counters[i]); + } + + free(entry->cpu_counters); + + ustctl_release_object(-1, entry->counter); + free(entry->counter); + + ustctl_destroy_counter(entry->daemon_counter); + + free(entry); +} + +static +bool ust_error_accounting_entry_get(struct ust_error_accounting_entry *entry) +{ + return urcu_ref_get_unless_zero(&entry->ref); +} + +static +void ust_error_accounting_entry_release(struct urcu_ref *entry_ref) +{ + struct ust_error_accounting_entry *entry = + container_of(entry_ref, typeof(*entry), ref); + + rcu_read_lock(); + cds_lfht_del(error_counter_uid_ht->ht, &entry->node.node); + call_rcu(&entry->rcu_head, free_ust_error_accounting_entry); + rcu_read_unlock(); +} + + +static +void ust_error_accounting_entry_put(struct ust_error_accounting_entry *entry) +{ + if (!entry) { + return; + } + + urcu_ref_put(&entry->ref, ust_error_accounting_entry_release); +} + +/* + * Put one reference to every UID entries. + */ +static +void put_ref_all_ust_error_accounting_entry(void) +{ + struct lttng_ht_iter iter; + struct ust_error_accounting_entry *uid_entry; + + ASSERT_LOCKED(the_event_notifier_counter.lock); + + rcu_read_lock(); + cds_lfht_for_each_entry(error_counter_uid_ht->ht, &iter.iter, + uid_entry, node.node) { + ust_error_accounting_entry_put(uid_entry); + } + + rcu_read_unlock(); +} + +/* + * Get one reference to every UID entries. + */ +static +void get_ref_all_ust_error_accounting_entry(void) +{ + struct lttng_ht_iter iter; + struct ust_error_accounting_entry *uid_entry; + + ASSERT_LOCKED(the_event_notifier_counter.lock); + + rcu_read_lock(); + cds_lfht_for_each_entry(error_counter_uid_ht->ht, &iter.iter, + uid_entry, node.node) { + ust_error_accounting_entry_get(uid_entry); + } + + rcu_read_unlock(); +} + +#endif /* HAVE_LIBLTTNG_UST_CTL */ + static enum event_notifier_error_accounting_status init_error_accounting_state(struct error_accounting_state *state, @@ -199,6 +300,10 @@ end: return status; } +/* + * Return the error counteur index associated to this event notifier tracer + * token. Returns _STATUS_OK if found and _STATUS_NOT_FOUND otherwise. + */ static enum event_notifier_error_accounting_status get_error_counter_index_for_token( struct error_accounting_state *state, uint64_t tracer_token, @@ -226,33 +331,49 @@ enum event_notifier_error_accounting_status get_error_counter_index_for_token( } #ifdef HAVE_LIBLTTNG_UST_CTL +/* + * Find the entry for this app's UID, the caller acquires a reference if the + * entry is found. + */ static -struct ust_error_accounting_entry *get_uid_accounting_entry(const struct ust_app *app) +struct ust_error_accounting_entry *ust_error_accounting_entry_find( + struct lttng_ht *uid_ht, const struct ust_app *app) { struct ust_error_accounting_entry *entry; struct lttng_ht_node_u64 *node; struct lttng_ht_iter iter; uint64_t key = app->uid; - lttng_ht_lookup(error_counter_uid_ht, &key, &iter); + lttng_ht_lookup(uid_ht, &key, &iter); node = lttng_ht_iter_get_node_u64(&iter); if(node == NULL) { entry = NULL; } else { - entry = caa_container_of(node, struct ust_error_accounting_entry, node); + bool got_ref; + + entry = caa_container_of(node, + struct ust_error_accounting_entry, node); + + got_ref = ust_error_accounting_entry_get(entry); + if (!got_ref) { + entry = NULL; + } } return entry; } +/* + * Create the entry for this app's UID, the caller acquires a reference to the + * entry, + */ static -struct ust_error_accounting_entry *create_uid_accounting_entry( - const struct ust_app *app) +struct ust_error_accounting_entry *ust_error_accounting_entry_create( + struct lttng_ht *uid_ht, const struct ust_app *app) { - int i, ret; + int i, ret, *cpu_counter_fds = NULL; struct ustctl_daemon_counter *daemon_counter; struct lttng_ust_abi_object_data *counter, **cpu_counters; - int *cpu_counter_fds = NULL; struct ust_error_accounting_entry *entry = NULL; const struct ustctl_counter_dimension dimension = { .size = ust_state.number_indices, @@ -266,6 +387,7 @@ struct ust_error_accounting_entry *create_uid_accounting_entry( goto error; } + urcu_ref_init(&entry->ref); entry->uid = app->uid; entry->nr_counter_cpu_fds = ustctl_get_nr_cpu_per_counter(); @@ -274,7 +396,6 @@ struct ust_error_accounting_entry *create_uid_accounting_entry( PERROR("Failed to allocate event notifier error counter file descriptors array: application uid = %d, application name = '%s', pid = %d, allocation size = %zu", (int) app->uid, app->name, (int) app->pid, entry->nr_counter_cpu_fds * sizeof(*cpu_counter_fds)); - ret = -1; goto error_counter_cpu_fds_alloc; } @@ -288,7 +409,6 @@ struct ust_error_accounting_entry *create_uid_accounting_entry( PERROR("Failed to allocate event notifier error counter lttng_ust_abi_object_data array: application uid = %d, application name = '%s', pid = %d, allocation size = %zu", (int) app->uid, app->name, (int) app->pid, entry->nr_counter_cpu_fds * sizeof(struct lttng_ust_abi_object_data *)); - ret = -1; goto error_counter_cpus_alloc; } @@ -336,7 +456,7 @@ struct ust_error_accounting_entry *create_uid_accounting_entry( entry->counter = counter; entry->cpu_counters = cpu_counters; - lttng_ht_node_init_u64(&entry->node, app->uid); + lttng_ht_node_init_u64(&entry->node, entry->uid); lttng_ht_add_unique_u64(error_counter_uid_ht, &entry->node); goto end; @@ -375,7 +495,8 @@ error_shm_alloc: ret = close(cpu_counter_fds[i]); if (ret) { - PERROR("Failed to close error counter per-CPU shm file descriptor: fd = %d", cpu_counter_fds[i]); + PERROR("Failed to close error counter per-CPU shm file descriptor: fd = %d", + cpu_counter_fds[i]); } } } @@ -470,13 +591,33 @@ event_notifier_error_accounting_register_app(struct ust_app *app) * app. If not, create one. */ rcu_read_lock(); - entry = get_uid_accounting_entry(app); + entry = ust_error_accounting_entry_find(error_counter_uid_ht, app); if (entry == NULL) { - entry = create_uid_accounting_entry(app); + /* + * Take the event notifier counter lock before creating the new + * entry to ensure that no event notifier is registered between + * the the entry creation and event notifier count check. + */ + pthread_mutex_lock(&the_event_notifier_counter.lock); + + entry = ust_error_accounting_entry_create(error_counter_uid_ht, + app); if (!entry) { status = EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_ERR; - goto end; + pthread_mutex_unlock(&the_event_notifier_counter.lock); + goto error_creating_entry; + } + + /* + * We just created a new UID entry, If there are event + * notifiers already registered, take one reference on their + * behalf. + */ + if (the_event_notifier_counter.count > 0) { + ust_error_accounting_entry_get(entry); } + + pthread_mutex_unlock(&the_event_notifier_counter.lock); } /* Duplicate counter object data. */ @@ -486,7 +627,7 @@ event_notifier_error_accounting_register_app(struct ust_app *app) ERR("Failed to duplicate event notifier error accounting counter for application user: application uid = %d, pid = %d, application name = '%s'", (int) app->uid, (int) app->pid, app->name); status = EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_ERR; - goto end; + goto error_duplicate_counter; } status = send_counter_data_to_ust(app, new_counter); @@ -571,6 +712,10 @@ error_allocate_cpu_counters: error_send_counter_data: ustctl_release_object(-1, new_counter); free(new_counter); +error_duplicate_counter: + ust_error_accounting_entry_put(entry); +error_creating_entry: + app->event_notifier_group.counter = NULL; end: rcu_read_unlock(); return status; @@ -584,12 +729,26 @@ event_notifier_error_accounting_unregister_app(struct ust_app *app) int i; rcu_read_lock(); - entry = get_uid_accounting_entry(app); + + /* If an error occurred during app registration no entry was created. */ + if (!app->event_notifier_group.counter) { + status = EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_OK; + goto end; + } + + entry = ust_error_accounting_entry_find(error_counter_uid_ht, app); if (entry == NULL) { ERR("Failed to find event notitifier error accounting entry on application teardown: pid = %d, application name = '%s'", app->pid, app->name); status = EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_ERR; goto end; + } else { + /* + * Put the entry twice as we acquired a reference from the + * `ust_error_accounting_entry_find()` above. + */ + ust_error_accounting_entry_put(entry); + ust_error_accounting_entry_put(entry); } for (i = 0; i < app->event_notifier_group.nr_counter_cpu; i++) { @@ -628,15 +787,7 @@ event_notifier_error_accounting_ust_get_count( get_trigger_info_for_log(trigger, &trigger_name, &trigger_owner_uid); - /* - * At the moment, the error counter index is domain wide. This means - * that if UID 1000 registers a event notifier and is allocated index 0 - * in it's error counter, index zero will be unused in error counter of - * all other users. - */ - status = get_error_counter_index_for_token( - &ust_state, - tracer_token, + status = get_error_counter_index_for_token(&ust_state, tracer_token, &error_counter_index); if (status != EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_OK) { @@ -706,16 +857,8 @@ enum event_notifier_error_accounting_status event_notifier_error_accounting_ust_ size_t dimension_index; const uint64_t tracer_token = lttng_trigger_get_tracer_token(trigger); - /* - * Go over all error counters (ignoring uid) as a trigger (and trigger - * errors) can be generated from any applications that this session - * daemon is managing. - */ - rcu_read_lock(); - status = get_error_counter_index_for_token( - &ust_state, - tracer_token, + status = get_error_counter_index_for_token(&ust_state, tracer_token, &error_counter_index); if (status != EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_OK) { uid_t trigger_owner_uid; @@ -733,6 +876,11 @@ enum event_notifier_error_accounting_status event_notifier_error_accounting_ust_ dimension_index = error_counter_index; + /* + * Go over all error counters (ignoring uid) as a trigger (and trigger + * errors) can be generated from any applications that this session + * daemon is managing. + */ cds_lfht_for_each_entry(error_counter_uid_ht->ht, &iter.iter, uid_entry, node.node) { const int ret = ustctl_counter_clear(uid_entry->daemon_counter, @@ -769,8 +917,7 @@ event_notifier_error_accounting_kernel_clear( enum event_notifier_error_accounting_status status; struct lttng_kernel_counter_clear counter_clear = {}; - status = get_error_counter_index_for_token( - &kernel_state, + status = get_error_counter_index_for_token(&kernel_state, lttng_trigger_get_tracer_token(trigger), &error_counter_index); if (status != EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_OK) { @@ -790,7 +937,7 @@ event_notifier_error_accounting_kernel_clear( counter_clear.index.dimension_indexes[0] = error_counter_index; ret = kernctl_counter_clear( - kernel_error_accountant.kernel_event_notifier_error_counter_fd, + kernel_error_accounting_entry.error_counter_fd, &counter_clear); if (ret) { uid_t trigger_owner_uid; @@ -851,7 +998,7 @@ event_notifier_error_accounting_register_kernel( DBG("Created kernel event notifier group error counter: fd = %d", error_counter_fd); - kernel_error_accountant.kernel_event_notifier_error_counter_fd = + kernel_error_accounting_entry.error_counter_fd = error_counter_fd; status = EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_OK; @@ -967,6 +1114,28 @@ event_notifier_error_accounting_register_event_notifier( break; } +#ifdef HAVE_LIBLTTNG_UST_CTL + switch (lttng_trigger_get_underlying_domain_type_restriction(trigger)) { + case LTTNG_DOMAIN_UST: + pthread_mutex_lock(&the_event_notifier_counter.lock); + the_event_notifier_counter.count++; + if (the_event_notifier_counter.count == 1) { + /* + * On the first event notifier, we get a reference to + * every existing UID entries. This ensures that the + * entries are kept around if there are still + * registered event notifiers but no apps. + */ + get_ref_all_ust_error_accounting_entry(); + } + pthread_mutex_unlock(&the_event_notifier_counter.lock); + break; + default: + break; + } +#endif /* HAVE_LIBLTTNG_UST_CTL */ + + end: return status; } @@ -981,8 +1150,7 @@ event_notifier_error_accounting_kernel_get_count( uint64_t error_counter_index; int ret; - status = get_error_counter_index_for_token( - &kernel_state, + status = get_error_counter_index_for_token(&kernel_state, lttng_trigger_get_tracer_token(trigger), &error_counter_index); if (status != EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_OK) { @@ -994,10 +1162,10 @@ event_notifier_error_accounting_kernel_get_count( counter_aggregate.index.number_dimensions = 1; counter_aggregate.index.dimension_indexes[0] = error_counter_index; - assert(kernel_error_accountant.kernel_event_notifier_error_counter_fd); + assert(kernel_error_accounting_entry.error_counter_fd); ret = kernctl_counter_get_aggregate_value( - kernel_error_accountant.kernel_event_notifier_error_counter_fd, + kernel_error_accounting_entry.error_counter_fd, &counter_aggregate); if (ret || counter_aggregate.value.value < 0) { uid_t trigger_owner_uid; @@ -1090,20 +1258,39 @@ void event_notifier_error_accounting_unregister_event_notifier( /* Trigger details already logged by callee on error. */ ERR("Failed to clear event notifier error counter during unregistration of event notifier: status = '%s'", error_accounting_status_str(status)); + goto end; } + rcu_read_lock(); + switch (lttng_trigger_get_underlying_domain_type_restriction(trigger)) { case LTTNG_DOMAIN_KERNEL: state = &kernel_state; break; +#ifdef HAVE_LIBLTTNG_UST_CTL case LTTNG_DOMAIN_UST: state = &ust_state; + + pthread_mutex_lock(&the_event_notifier_counter.lock); + the_event_notifier_counter.count--; + if (the_event_notifier_counter.count == 0) { + + /* + * When unregistering the last event notifier, put one + * reference to every uid entries on the behalf of all + * event notifiers. + */ + put_ref_all_ust_error_accounting_entry(); + } + + pthread_mutex_unlock(&the_event_notifier_counter.lock); + break; +#endif /* HAVE_LIBLTTNG_UST_CTL */ default: abort(); } - rcu_read_lock(); lttng_ht_lookup(state->indices_ht, &tracer_token, &iter); node = lttng_ht_iter_get_node_u64(&iter); if (node) { @@ -1133,61 +1320,20 @@ void event_notifier_error_accounting_unregister_event_notifier( call_rcu(&index_entry->rcu_head, free_index_ht_entry); } +end: rcu_read_unlock(); } -#ifdef HAVE_LIBLTTNG_UST_CTL -static void free_error_account_entry(struct rcu_head *head) -{ - int i; - struct ust_error_accounting_entry *entry = - caa_container_of(head, typeof(*entry), rcu_head); - - for (i = 0; i < entry->nr_counter_cpu_fds; i++) { - ustctl_release_object(-1, entry->cpu_counters[i]); - free(entry->cpu_counters[i]); - } - - free(entry->cpu_counters); - - ustctl_release_object(-1, entry->counter); - free(entry->counter); - - ustctl_destroy_counter(entry->daemon_counter); - - free(entry); -} -#else -/* Not called without UST support. */ -static void free_error_account_entry(struct rcu_head *head) {} -#endif /* HAVE_LIBLTTNG_UST_CTL */ - void event_notifier_error_accounting_fini(void) { - struct lttng_ht_iter iter; - struct ust_error_accounting_entry *uid_entry; - - if (kernel_error_accountant.kernel_event_notifier_error_counter_fd) { - const int ret = close(kernel_error_accountant.kernel_event_notifier_error_counter_fd); + if (kernel_error_accounting_entry.error_counter_fd) { + const int ret = close(kernel_error_accounting_entry.error_counter_fd); if (ret) { PERROR("Failed to close kernel event notifier error counter"); } } - /* - * FIXME error account entries are not reference-counted and torn - * down on last use. They exist from the moment of their first use - * up until the teardown of the session daemon. - */ - rcu_read_lock(); - cds_lfht_for_each_entry(error_counter_uid_ht->ht, &iter.iter, - uid_entry, node.node) { - cds_lfht_del(error_counter_uid_ht->ht, &uid_entry->node.node); - call_rcu(&uid_entry->rcu_head, free_error_account_entry); - } - rcu_read_unlock(); - lttng_ht_destroy(error_counter_uid_ht); fini_error_accounting_state(&kernel_state); diff --git a/src/bin/lttng-sessiond/ust-app.c b/src/bin/lttng-sessiond/ust-app.c index 97cb66232..f44a30d1b 100644 --- a/src/bin/lttng-sessiond/ust-app.c +++ b/src/bin/lttng-sessiond/ust-app.c @@ -4069,7 +4069,8 @@ int ust_app_setup_event_notifier_group(struct ust_app *app) /* Assign handle only when the complete setup is valid. */ app->event_notifier_group.object = event_notifier_group; - event_notifier_error_accounting_status = event_notifier_error_accounting_register_app(app); + event_notifier_error_accounting_status = + event_notifier_error_accounting_register_app(app); if (event_notifier_error_accounting_status != EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_OK) { if (event_notifier_error_accounting_status == EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_APP_DEAD) { DBG3("Failed to setup event notifier error accounting (application is dead): app socket fd = %d", diff --git a/tests/regression/tools/notification/test_notification_notifier_discarded_count b/tests/regression/tools/notification/test_notification_notifier_discarded_count index 5df86d605..9320140d3 100755 --- a/tests/regression/tools/notification/test_notification_notifier_discarded_count +++ b/tests/regression/tools/notification/test_notification_notifier_discarded_count @@ -28,7 +28,7 @@ FULL_LTTNG_BIN="${TESTDIR}/../src/bin/lttng/${LTTNG_BIN}" FULL_LTTNG_SESSIOND_BIN="${TESTDIR}/../src/bin/lttng-sessiond/lttng-sessiond" UST_NUM_TESTS=15 -DESTRUCTIVE_TESTS_NUM=8 +DESTRUCTIVE_TESTS_NUM=12 KERNEL_NUM_TESTS=$((14 + $DESTRUCTIVE_TESTS_NUM)) NUM_TESTS=$(($UST_NUM_TESTS + $KERNEL_NUM_TESTS)) @@ -200,7 +200,7 @@ function test_ust_notifier_discarded_count # Remove the notifier. lttng_remove_trigger_ok "$trigger_name" - # Confirm that no notifier is enabled. + # Confirm that no trigger is enabled. list_triggers_line_count=$("$FULL_LTTNG_BIN" list-triggers | wc -l) is "$list_triggers_line_count" "0" "No \`event-rule-matches\` userspace notifier enabled as expected" @@ -304,9 +304,9 @@ function test_ust_notifier_discarded_count_multi_uid user_trigger_discarded_nb=$(trigger_get_discarded_notif_number "$user_trigger_name") isnt $root_trigger_discarded_nb 0 \ - "Root trigger discard notifications number ($root_trigger_discarded_nb) is non-zero" + "Root trigger discarded notifications number ($root_trigger_discarded_nb) is non-zero" isnt $user_trigger_discarded_nb 0 \ - "User trigger discard notifications number ($user_trigger_discarded_nb) is non-zero" + "User trigger discarded notifications number ($user_trigger_discarded_nb) is non-zero" lttng_remove_trigger_ok "$root_trigger_name" lttng_remove_trigger_ok "$user_trigger_name" --user-id "$new_uid" @@ -319,6 +319,75 @@ function test_ust_notifier_discarded_count_multi_uid rm -f "$list_triggers_stdout" } +function test_ust_notifier_discarded_regardless_trigger_owner +{ + local sessiond_pipe=() + local root_trigger_name="root_trigger" + local user_trigger_name="user_trigger" + local list_triggers_stdout=$(mktemp -t list_triggers_stdout.XXXXXX) + local NR_USEC_WAIT=0 + local PIPE_SIZE + local NR_ITER + local new_user="dummy_lttng_test_user" + + PIPE_SIZE=$("$CURDIR"/default_pipe_size_getter) + if [ $? -ne 0 ]; then + BAIL_OUT "Failed to get system default pipe size" + else + diag "Default system pipe size: $PIPE_SIZE bytes" + fi + + # Find the number of events needed to overflow the event notification + # pipe buffer. Each LTTng-UST notification is at least 42 bytes long. + # Double that number to ensure enough events are created to overflow + # the buffer. + NR_ITER=$(( (PIPE_SIZE / 42) * 2 )) + diag "Test applications will emit $NR_ITER events" + + diag "UST event notifer error counter persists when a root trigger is present" + + # Create a dummy user to run test apps as. + useradd --no-create-home "$new_user" + new_uid=$(id -u "$new_user") + + # Used on sessiond launch. + LTTNG_SESSIOND_ENV_VARS="LTTNG_TESTPOINT_ENABLE=1 \ + NOTIFIER_PAUSE_PIPE_PATH=${TESTPOINT_PIPE_PATH} \ + LD_PRELOAD=${TESTPOINT}" + + start_lttng_sessiond_notap + + # This is needed since the testpoint create a pipe with the sessiond + # type suffixed. + for f in "$TESTPOINT_BASE_PATH"*; do + sessiond_pipe+=("$f") + done + + lttng_add_trigger_ok "$root_trigger_name" \ + --condition on-event --userspace tp:tptest \ + --action notify + + # Stop consumption of notifier tracer notifications. + echo -n 1 > $sessiond_pipe + + su "$new_user" -c "$TESTAPP_BIN -i $NR_ITER -w $NR_USEC_WAIT" + ok $? "Generating $NR_ITER tracer notifications as UID: $new_uid" + + root_trigger_discarded_nb=$(trigger_get_discarded_notif_number "$root_trigger_name") + + isnt $root_trigger_discarded_nb 0 \ + "Root trigger discarded notifications number ($root_trigger_discarded_nb) is non-zero" + + lttng_remove_trigger_ok "$root_trigger_name" + + stop_lttng_sessiond_notap + + unset LTTNG_SESSIOND_ENV_VARS + + userdel "$new_user" + rm -f "$list_triggers_stdout" +} + test_ust_notifier_discarded_count test_ust_notifier_discarded_count_max_bucket @@ -332,10 +401,11 @@ if [ "$(id -u)" == "0" ]; then test_kernel_notifier_discarded_count_max_bucket if destructive_tests_enabled ; then - # This test adds a new user on the system. Since it's a quite + # Those tests add a new user on the system. Since it's a quite # intrusive change to the system, we decide to only run it when # the user knows what they are doing. test_ust_notifier_discarded_count_multi_uid + test_ust_notifier_discarded_regardless_trigger_owner else skip 0 "You need to set the LTTNG_ENABLE_DESTRUCTIVE_TESTS environment variable to \"will-break-my-system\" to run this test" $DESTRUCTIVE_TESTS_NUM fi