#include <common/compat/errno.h>
#include <common/common.h>
+#include <common/hashtable/utils.h>
+#include <lttng/event-rule/event-rule.h>
+#include <lttng/event-rule/event-rule-internal.h>
+#include <lttng/event-rule/tracepoint.h>
+#include <lttng/condition/condition.h>
+#include <lttng/condition/event-rule-internal.h>
+#include <lttng/condition/event-rule.h>
#include <common/sessiond-comm/sessiond-comm.h>
#include "buffer-registry.h"
free(ua_event);
}
+/*
+ * Delayed reclaim of a ust_app_event_notifier_rule object. This MUST be called
+ * through a call_rcu().
+ */
+static
+void free_ust_app_event_notifier_rule_rcu(struct rcu_head *head)
+{
+ struct ust_app_event_notifier_rule *obj = caa_container_of(
+ head, struct ust_app_event_notifier_rule, rcu_head);
+
+ free(obj);
+}
+
+/*
+ * Delete ust app event notifier rule safely.
+ */
+static void delete_ust_app_event_notifier_rule(int sock,
+ struct ust_app_event_notifier_rule *ua_event_notifier_rule,
+ struct ust_app *app)
+{
+ int ret;
+
+ assert(ua_event_notifier_rule);
+
+ if (ua_event_notifier_rule->exclusion != NULL) {
+ free(ua_event_notifier_rule->exclusion);
+ }
+
+ if (ua_event_notifier_rule->obj != NULL) {
+ pthread_mutex_lock(&app->sock_lock);
+ ret = ustctl_release_object(sock, ua_event_notifier_rule->obj);
+ pthread_mutex_unlock(&app->sock_lock);
+ if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("Failed to release event notifier object: app = '%s' (ppid %d), ret = %d",
+ app->name, (int) app->ppid, ret);
+ }
+
+ free(ua_event_notifier_rule->obj);
+ }
+
+ lttng_event_rule_put(ua_event_notifier_rule->event_rule);
+ call_rcu(&ua_event_notifier_rule->rcu_head,
+ free_ust_app_event_notifier_rule_rcu);
+}
+
/*
* Release ust data object of the given stream.
*
{
int ret, sock;
struct ust_app_session *ua_sess, *tmp_ua_sess;
+ struct lttng_ht_iter iter;
+ struct ust_app_event_notifier_rule *event_notifier_rule;
+ bool event_notifier_write_fd_is_open;
/*
* The session list lock must be held during this function to guarantee
rcu_read_unlock();
}
+ /* Remove the event notifier rules associated with this app. */
+ rcu_read_lock();
+ cds_lfht_for_each_entry (app->token_to_event_notifier_rule_ht->ht,
+ &iter.iter, event_notifier_rule, node.node) {
+ ret = lttng_ht_del(app->token_to_event_notifier_rule_ht, &iter);
+ assert(!ret);
+
+ delete_ust_app_event_notifier_rule(
+ app->sock, event_notifier_rule, app);
+ }
+
+ rcu_read_unlock();
+
ht_cleanup_push(app->sessions);
ht_cleanup_push(app->ust_sessions_objd);
ht_cleanup_push(app->ust_objd);
+ ht_cleanup_push(app->token_to_event_notifier_rule_ht);
/*
* This could be NULL if the event notifier setup failed (e.g the app
free(app->event_notifier_group.object);
}
+ event_notifier_write_fd_is_open = lttng_pipe_is_write_open(
+ app->event_notifier_group.event_pipe);
lttng_pipe_destroy(app->event_notifier_group.event_pipe);
+ /*
+ * Release the file descriptors reserved for the event notifier pipe.
+ * The app could be destroyed before the write end of the pipe could be
+ * passed to the application (and closed). In that case, both file
+ * descriptors must be released.
+ */
+ lttng_fd_put(LTTNG_FD_APPS, event_notifier_write_fd_is_open ? 2 : 1);
/*
* Wait until we have deleted the application from the sock hash table
return NULL;
}
+/*
+ * Allocate a new UST app event notifier rule.
+ */
+static struct ust_app_event_notifier_rule *alloc_ust_app_event_notifier_rule(
+ struct lttng_event_rule *event_rule, uint64_t token)
+{
+ enum lttng_event_rule_generate_exclusions_status
+ generate_exclusion_status;
+ struct ust_app_event_notifier_rule *ua_event_notifier_rule;
+
+ ua_event_notifier_rule = zmalloc(sizeof(struct ust_app_event_notifier_rule));
+ if (ua_event_notifier_rule == NULL) {
+ PERROR("Failed to allocate ust_app_event_notifier_rule structure");
+ goto error;
+ }
+
+ ua_event_notifier_rule->enabled = 1;
+ ua_event_notifier_rule->token = token;
+ lttng_ht_node_init_u64(&ua_event_notifier_rule->node, token);
+
+ /* Get reference of the event rule. */
+ if (!lttng_event_rule_get(event_rule)) {
+ abort();
+ }
+
+ ua_event_notifier_rule->event_rule = event_rule;
+ ua_event_notifier_rule->filter = lttng_event_rule_get_filter_bytecode(event_rule);
+ generate_exclusion_status = lttng_event_rule_generate_exclusions(
+ event_rule, &ua_event_notifier_rule->exclusion);
+ switch (generate_exclusion_status) {
+ case LTTNG_EVENT_RULE_GENERATE_EXCLUSIONS_STATUS_OK:
+ case LTTNG_EVENT_RULE_GENERATE_EXCLUSIONS_STATUS_NONE:
+ break;
+ default:
+ /* Error occured. */
+ ERR("Failed to generate exclusions from event rule while allocating an event notifier rule");
+ goto error_put_event_rule;
+ }
+
+ DBG3("UST app event notifier rule allocated: token = %" PRIu64,
+ ua_event_notifier_rule->token);
+
+ return ua_event_notifier_rule;
+
+error_put_event_rule:
+ lttng_event_rule_put(event_rule);
+error:
+ free(ua_event_notifier_rule);
+ return NULL;
+}
+
/*
* Alloc new UST app context.
*/
return event;
}
+/*
+ * Look-up an event notifier rule based on its token id.
+ *
+ * Must be called with the RCU read lock held.
+ * Return an ust_app_event_notifier_rule object or NULL on error.
+ */
+static struct ust_app_event_notifier_rule *find_ust_app_event_notifier_rule(
+ struct lttng_ht *ht, uint64_t token)
+{
+ struct lttng_ht_iter iter;
+ struct lttng_ht_node_u64 *node;
+ struct ust_app_event_notifier_rule *event_notifier_rule = NULL;
+
+ assert(ht);
+
+ lttng_ht_lookup(ht, &token, &iter);
+ node = lttng_ht_iter_get_node_u64(&iter);
+ if (node == NULL) {
+ DBG2("UST app event notifier rule token not found: token = %" PRIu64,
+ token);
+ goto end;
+ }
+
+ event_notifier_rule = caa_container_of(
+ node, struct ust_app_event_notifier_rule, node);
+end:
+ return event_notifier_rule;
+}
+
/*
* Create the channel context on the tracer.
*
return ret;
}
+static int init_ust_event_notifier_from_event_rule(
+ const struct lttng_event_rule *rule,
+ struct lttng_ust_event_notifier *event_notifier)
+{
+ enum lttng_event_rule_status status;
+ enum lttng_loglevel_type loglevel_type;
+ enum lttng_ust_loglevel_type ust_loglevel_type = LTTNG_UST_LOGLEVEL_ALL;
+ int loglevel = -1, ret = 0;
+ const char *pattern;
+
+ /* For now only LTTNG_EVENT_RULE_TYPE_TRACEPOINT are supported. */
+ assert(lttng_event_rule_get_type(rule) ==
+ LTTNG_EVENT_RULE_TYPE_TRACEPOINT);
+
+ memset(event_notifier, 0, sizeof(*event_notifier));
+
+ status = lttng_event_rule_tracepoint_get_pattern(rule, &pattern);
+ if (status != LTTNG_EVENT_RULE_STATUS_OK) {
+ /* At this point, this is a fatal error. */
+ abort();
+ }
+
+ status = lttng_event_rule_tracepoint_get_log_level_type(
+ rule, &loglevel_type);
+ if (status != LTTNG_EVENT_RULE_STATUS_OK) {
+ /* At this point, this is a fatal error. */
+ abort();
+ }
+
+ switch (loglevel_type) {
+ case LTTNG_EVENT_LOGLEVEL_ALL:
+ ust_loglevel_type = LTTNG_UST_LOGLEVEL_ALL;
+ break;
+ case LTTNG_EVENT_LOGLEVEL_RANGE:
+ ust_loglevel_type = LTTNG_UST_LOGLEVEL_RANGE;
+ break;
+ case LTTNG_EVENT_LOGLEVEL_SINGLE:
+ ust_loglevel_type = LTTNG_UST_LOGLEVEL_SINGLE;
+ break;
+ default:
+ /* Unknown log level specification type. */
+ abort();
+ }
+
+ if (loglevel_type != LTTNG_EVENT_LOGLEVEL_ALL) {
+ status = lttng_event_rule_tracepoint_get_log_level(
+ rule, &loglevel);
+ assert(status == LTTNG_EVENT_RULE_STATUS_OK);
+ }
+
+ event_notifier->event.instrumentation = LTTNG_UST_TRACEPOINT;
+ ret = lttng_strncpy(event_notifier->event.name, pattern,
+ LTTNG_UST_SYM_NAME_LEN - 1);
+ if (ret) {
+ ERR("Failed to copy event rule pattern to notifier: pattern = '%s' ",
+ pattern);
+ goto end;
+ }
+
+ event_notifier->event.loglevel_type = ust_loglevel_type;
+ event_notifier->event.loglevel = loglevel;
+end:
+ return ret;
+}
+
+/*
+ * Create the specified event notifier against the user space tracer of a
+ * given application.
+ */
+static int create_ust_event_notifier(struct ust_app *app,
+ struct ust_app_event_notifier_rule *ua_event_notifier_rule)
+{
+ int ret = 0;
+ struct lttng_ust_event_notifier event_notifier;
+
+ health_code_update();
+ assert(app->event_notifier_group.object);
+
+ ret = init_ust_event_notifier_from_event_rule(
+ ua_event_notifier_rule->event_rule, &event_notifier);
+ if (ret) {
+ ERR("Failed to initialize UST event notifier from event rule: app = '%s' (ppid: %d)",
+ app->name, app->ppid);
+ goto error;
+ }
+
+ event_notifier.event.token = ua_event_notifier_rule->token;
+
+ /* Create UST event notifier against the tracer. */
+ pthread_mutex_lock(&app->sock_lock);
+ ret = ustctl_create_event_notifier(app->sock, &event_notifier,
+ app->event_notifier_group.object,
+ &ua_event_notifier_rule->obj);
+ pthread_mutex_unlock(&app->sock_lock);
+ if (ret < 0) {
+ if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
+ ERR("Error ustctl create event notifier: name = '%s', app = '%s' (ppid: %d), ret = %d",
+ event_notifier.event.name, app->name,
+ app->ppid, ret);
+ } else {
+ /*
+ * This is normal behavior, an application can die
+ * during the creation process. Don't report an error so
+ * the execution can continue normally.
+ */
+ ret = 0;
+ DBG3("UST app create event notifier failed (application is dead): app = '%s' (ppid = %d)",
+ app->name, app->ppid);
+ }
+
+ goto error;
+ }
+
+ ua_event_notifier_rule->handle = ua_event_notifier_rule->obj->handle;
+
+ DBG2("UST app event notifier %s created successfully: app = '%s' (ppid: %d), object: %p",
+ event_notifier.event.name, app->name, app->ppid,
+ ua_event_notifier_rule->obj);
+
+ health_code_update();
+
+ /* Set filter if one is present. */
+ if (ua_event_notifier_rule->filter) {
+ ret = set_ust_object_filter(app, ua_event_notifier_rule->filter,
+ ua_event_notifier_rule->obj);
+ if (ret < 0) {
+ goto error;
+ }
+ }
+
+ /* Set exclusions for the event. */
+ if (ua_event_notifier_rule->exclusion) {
+ ret = set_ust_object_exclusions(app,
+ ua_event_notifier_rule->exclusion,
+ ua_event_notifier_rule->obj);
+ if (ret < 0) {
+ goto error;
+ }
+ }
+
+ /*
+ * We now need to explicitly enable the event, since it
+ * is disabled at creation.
+ */
+ ret = enable_ust_object(app, ua_event_notifier_rule->obj);
+ if (ret < 0) {
+ /*
+ * If we hit an EPERM, something is wrong with our enable call.
+ * If we get an EEXIST, there is a problem on the tracer side
+ * since we just created it.
+ */
+ switch (ret) {
+ case -LTTNG_UST_ERR_PERM:
+ /* Code flow problem. */
+ abort();
+ case -LTTNG_UST_ERR_EXIST:
+ /* It's OK for our use case. */
+ ret = 0;
+ break;
+ default:
+ break;
+ }
+
+ goto error;
+ }
+
+ ua_event_notifier_rule->enabled = true;
+
+error:
+ health_code_update();
+ return ret;
+}
+
/*
* Copy data between an UST app event and a LTT event.
*/
/*
* Create UST app event and create it on the tracer side.
*
+ * Must be called with the RCU read side lock held.
* Called with ust app session mutex held.
*/
static
add_unique_ust_app_event(ua_chan, ua_event);
- DBG2("UST app create event %s for PID %d completed", ua_event->name,
- app->pid);
+ DBG2("UST app create event completed: app = '%s' (ppid: %d)",
+ app->name, app->ppid);
end:
return ret;
return ret;
}
+/*
+ * Create UST app event notifier rule and create it on the tracer side.
+ *
+ * Must be called with the RCU read side lock held.
+ * Called with ust app session mutex held.
+ */
+static
+int create_ust_app_event_notifier_rule(struct lttng_event_rule *rule,
+ struct ust_app *app, uint64_t token)
+{
+ int ret = 0;
+ struct ust_app_event_notifier_rule *ua_event_notifier_rule;
+
+ ua_event_notifier_rule = alloc_ust_app_event_notifier_rule(rule, token);
+ if (ua_event_notifier_rule == NULL) {
+ ret = -ENOMEM;
+ goto end;
+ }
+
+ /* Create it on the tracer side. */
+ ret = create_ust_event_notifier(app, ua_event_notifier_rule);
+ if (ret < 0) {
+ /*
+ * Not found previously means that it does not exist on the
+ * tracer. If the application reports that the event existed,
+ * it means there is a bug in the sessiond or lttng-ust
+ * (or corruption, etc.)
+ */
+ if (ret == -LTTNG_UST_ERR_EXIST) {
+ ERR("Tracer for application reported that an event notifier being created already exists: "
+ "token = \"%" PRIu64 "\", pid = %d, ppid = %d, uid = %d, gid = %d",
+ token,
+ app->pid, app->ppid, app->uid,
+ app->gid);
+ }
+ goto error;
+ }
+
+ lttng_ht_add_unique_u64(app->token_to_event_notifier_rule_ht,
+ &ua_event_notifier_rule->node);
+
+ DBG2("UST app create token event rule completed: app = '%s' (ppid: %d), token = %" PRIu64,
+ app->name, app->ppid, token);
+
+end:
+ return ret;
+
+error:
+ /* The RCU read side lock is already being held by the caller. */
+ delete_ust_app_event_notifier_rule(-1, ua_event_notifier_rule, app);
+ return ret;
+}
+
/*
* Create UST metadata and open it on the tracer side.
*
*/
struct ust_app *ust_app_create(struct ust_register_msg *msg, int sock)
{
+ int ret;
struct ust_app *lta = NULL;
struct lttng_pipe *event_notifier_event_source_pipe = NULL;
goto error;
}
+ /*
+ * Reserve the two file descriptors of the event source pipe. The write
+ * end will be closed once it is passed to the application, at which
+ * point a single 'put' will be performed.
+ */
+ ret = lttng_fd_get(LTTNG_FD_APPS, 2);
+ if (ret) {
+ ERR("Failed to reserve two file descriptors for the event source pipe while creating a new application instance: app = '%s' (ppid: %d)",
+ msg->name, (int) msg->ppid);
+ goto error;
+ }
+
event_notifier_event_source_pipe = lttng_pipe_open(FD_CLOEXEC);
if (!event_notifier_event_source_pipe) {
PERROR("Failed to open application event source pipe: '%s' (ppid = %d)",
lta->ust_objd = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
lta->ust_sessions_objd = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
lta->notify_sock = -1;
+ lta->token_to_event_notifier_rule_ht = lttng_ht_new(0, LTTNG_HT_TYPE_U64);
/* Copy name and make sure it's NULL terminated. */
strncpy(lta->name, msg->name, sizeof(lta->name));
error_free_pipe:
lttng_pipe_destroy(event_notifier_event_source_pipe);
+ lttng_fd_put(LTTNG_FD_APPS, 2);
error:
return NULL;
}
goto error;
}
+ ret = lttng_pipe_write_close(app->event_notifier_group.event_pipe);
+ if (ret) {
+ ERR("Failed to close write end of the application's event source pipe: app = '%s' (ppid = %d)",
+ app->name, app->ppid);
+ goto error;
+ }
+
+ /*
+ * Release the file descriptor that was reserved for the write-end of
+ * the pipe.
+ */
+ lttng_fd_put(LTTNG_FD_APPS, 1);
+
lttng_ret = notification_thread_command_add_tracer_event_source(
notification_thread_handle,
lttng_pipe_get_readfd(app->event_notifier_group.event_pipe),
if (ust_app_ht_by_notify_sock) {
cds_lfht_for_each_entry(ust_app_ht_by_notify_sock->ht, &iter.iter, app,
notify_sock_n.node) {
- struct cds_lfht_node *node;
- struct ust_app *app;
-
- node = cds_lfht_iter_get_node(&iter.iter);
- if (!node) {
- continue;
- }
+ /*
+ * Assert that all notifiers are gone as all triggers
+ * are unregistered prior to this clean-up.
+ */
+ assert(lttng_ht_get_count(app->token_to_event_notifier_rule_ht) == 0);
- app = container_of(node, struct ust_app,
- notify_sock_n.node);
ust_app_notify_sock_unregister(app->notify_sock);
}
}
return ret;
}
+/* Called with RCU read-side lock held. */
+static
+void ust_app_synchronize_event_notifier_rules(struct ust_app *app)
+{
+ int ret = 0;
+ enum lttng_error_code ret_code;
+ enum lttng_trigger_status t_status;
+ struct lttng_ht_iter app_trigger_iter;
+ struct lttng_triggers *triggers = NULL;
+ struct ust_app_event_notifier_rule *event_notifier_rule;
+ unsigned int count, i;
+
+ /*
+ * Currrently, registering or unregistering a trigger with an
+ * event rule condition causes a full synchronization of the event
+ * notifiers.
+ *
+ * The first step attempts to add an event notifier for all registered
+ * triggers that apply to the user space tracers. Then, the
+ * application's event notifiers rules are all checked against the list
+ * of registered triggers. Any event notifier that doesn't have a
+ * matching trigger can be assumed to have been disabled.
+ *
+ * All of this is inefficient, but is put in place to get the feature
+ * rolling as it is simpler at this moment. It will be optimized Soon™
+ * to allow the state of enabled
+ * event notifiers to be synchronized in a piece-wise way.
+ */
+
+ /* Get all triggers using uid 0 (root) */
+ ret_code = notification_thread_command_list_triggers(
+ notification_thread_handle, 0, &triggers);
+ if (ret_code != LTTNG_OK) {
+ ret = -1;
+ goto end;
+ }
+
+ assert(triggers);
+
+ t_status = lttng_triggers_get_count(triggers, &count);
+ if (t_status != LTTNG_TRIGGER_STATUS_OK) {
+ ret = -1;
+ goto end;
+ }
+
+ for (i = 0; i < count; i++) {
+ struct lttng_condition *condition;
+ struct lttng_event_rule *event_rule;
+ struct lttng_trigger *trigger;
+ const struct ust_app_event_notifier_rule *looked_up_event_notifier_rule;
+ enum lttng_condition_status condition_status;
+ uint64_t token;
+
+ trigger = lttng_triggers_borrow_mutable_at_index(triggers, i);
+ assert(trigger);
+
+ token = lttng_trigger_get_tracer_token(trigger);
+ condition = lttng_trigger_get_condition(trigger);
+
+ if (lttng_condition_get_type(condition) != LTTNG_CONDITION_TYPE_EVENT_RULE_HIT) {
+ /* Does not apply */
+ continue;
+ }
+
+ condition_status = lttng_condition_event_rule_borrow_rule_mutable(condition, &event_rule);
+ assert(condition_status == LTTNG_CONDITION_STATUS_OK);
+
+ if (lttng_event_rule_get_domain_type(event_rule) == LTTNG_DOMAIN_KERNEL) {
+ /* Skip kernel related triggers. */
+ continue;
+ }
+
+ /*
+ * Find or create the associated token event rule. The caller
+ * holds the RCU read lock, so this is safe to call without
+ * explicitly acquiring it here.
+ */
+ looked_up_event_notifier_rule = find_ust_app_event_notifier_rule(
+ app->token_to_event_notifier_rule_ht, token);
+ if (!looked_up_event_notifier_rule) {
+ ret = create_ust_app_event_notifier_rule(event_rule, app, token);
+ if (ret < 0) {
+ goto end;
+ }
+ }
+ }
+
+ rcu_read_lock();
+ /* Remove all unknown event sources from the app. */
+ cds_lfht_for_each_entry (app->token_to_event_notifier_rule_ht->ht,
+ &app_trigger_iter.iter, event_notifier_rule,
+ node.node) {
+ const uint64_t app_token = event_notifier_rule->token;
+ bool found = false;
+
+ /*
+ * Check if the app event trigger still exists on the
+ * notification side.
+ */
+ for (i = 0; i < count; i++) {
+ uint64_t notification_thread_token;
+ const struct lttng_trigger *trigger =
+ lttng_triggers_get_at_index(
+ triggers, i);
+
+ assert(trigger);
+
+ notification_thread_token =
+ lttng_trigger_get_tracer_token(trigger);
+
+ if (notification_thread_token == app_token) {
+ found = true;
+ break;
+ }
+ }
+
+ if (found) {
+ /* Still valid. */
+ continue;
+ }
+
+ /*
+ * This trigger was unregistered, disable it on the tracer's
+ * side.
+ */
+ ret = lttng_ht_del(app->token_to_event_notifier_rule_ht,
+ &app_trigger_iter);
+ assert(ret == 0);
+
+ /* Callee logs errors. */
+ (void) disable_ust_object(app, event_notifier_rule->obj);
+
+ delete_ust_app_event_notifier_rule(
+ app->sock, event_notifier_rule, app);
+ }
+
+ rcu_read_unlock();
+
+end:
+ lttng_triggers_destroy(triggers);
+ return;
+}
+
/*
* The caller must ensure that the application is compatible and is tracked
* by the process attribute trackers.
}
}
+/*
+ * Add all event notifiers to an application.
+ *
+ * Called with session lock held.
+ * Called with RCU read-side lock held.
+ */
+void ust_app_global_update_event_notifier_rules(struct ust_app *app)
+{
+ DBG2("UST application global event notifier rules update: app = '%s' (ppid: %d)",
+ app->name, app->ppid);
+
+ if (!app->compatible) {
+ return;
+ }
+
+ if (app->event_notifier_group.object == NULL) {
+ WARN("UST app global update of event notifiers for app skipped since communication handle is null: app = '%s' (ppid: %d)",
+ app->name, app->ppid);
+ return;
+ }
+
+ ust_app_synchronize_event_notifier_rules(app);
+}
+
/*
* Called with session lock held.
*/
rcu_read_unlock();
}
+void ust_app_global_update_all_event_notifier_rules(void)
+{
+ struct lttng_ht_iter iter;
+ struct ust_app *app;
+
+ rcu_read_lock();
+ cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
+ ust_app_global_update_event_notifier_rules(app);
+ }
+
+ rcu_read_unlock();
+}
+
/*
* Add context to a specific channel for global UST domain.
*/
projects / lttng-tools.git / blobdiff