#include <common/config/session-config.h>
#include <common/defaults.h>
#include <common/utils.h>
-#include <common/futex.h>
#include <common/align.h>
#include <common/time.h>
#include <sys/eventfd.h>
#include <urcu/list.h>
#include <urcu/rculfhash.h>
-/**
- * This thread maintains an internal state associating clients and triggers.
- *
- * In order to speed-up and simplify queries, hash tables providing the
- * following associations are maintained:
- *
- * - client_socket_ht: associate a client's socket (fd) to its "struct client"
- * This hash table owns the "struct client" which must thus be
- * disposed-of on removal from the hash table.
- *
- * - channel_triggers_ht:
- * associates a channel key to a list of
- * struct lttng_trigger_list_nodes. The triggers in this list are
- * those that have conditions that apply to this channel.
- * This hash table owns the list, but not the triggers themselves.
- *
- * - channel_state_ht:
- * associates a pair (channel key, channel domain) to its last
- * sampled state received from the consumer daemon
- * (struct channel_state).
- * This previous sample is kept to implement edge-triggered
- * conditions as we need to detect the state transitions.
- * This hash table owns the channel state.
- *
- * - notification_trigger_clients_ht:
- * associates notification-emitting triggers to clients
- * (struct notification_client_ht_node) subscribed to those
- * conditions.
- * The condition's hash and match functions are used directly since
- * all triggers in this hash table have the "notify" action.
- * This hash table holds no ownership.
- *
- * - channels_ht:
- * associates a channel_key to a struct channel_info. The hash table
- * holds the ownership of the struct channel_info.
- *
- * - triggers_ht:
- * associated a condition to a struct lttng_trigger_ht_element.
- * The hash table holds the ownership of the
- * lttng_trigger_ht_elements along with the triggers themselves.
- *
- * The thread reacts to the following internal events:
- * 1) creation of a tracing channel,
- * 2) destruction of a tracing channel,
- * 3) registration of a trigger,
- * 4) unregistration of a trigger,
- * 5) reception of a channel monitor sample from the consumer daemon.
- *
- * Events specific to notification-emitting triggers:
- * 6) connection of a notification client,
- * 7) disconnection of a notification client,
- * 8) subscription of a client to a conditions' notifications,
- * 9) unsubscription of a client from a conditions' notifications,
- *
- *
- * 1) Creation of a tracing channel
- * - notification_trigger_clients_ht is traversed to identify
- * triggers which apply to this new channel,
- * - triggers identified are added to the channel_triggers_ht.
- * - add channel to channels_ht
- *
- * 2) Destruction of a tracing channel
- * - remove entry from channel_triggers_ht, releasing the list wrapper and
- * elements,
- * - remove entry from the channel_state_ht.
- * - remove channel from channels_ht
- *
- * 3) Registration of a trigger
- * - if the trigger's action is of type "notify",
- * - traverse the list of conditions of every client to build a list of
- * clients which have to be notified when this trigger's condition is met,
- * - add list of clients (even if it is empty) to the
- * notification_trigger_clients_ht,
- * - add trigger to channel_triggers_ht (if applicable),
- * - add trigger to triggers_ht
- *
- * 4) Unregistration of a trigger
- * - if the trigger's action is of type "notify",
- * - remove the trigger from the notification_trigger_clients_ht,
- * - remove trigger from channel_triggers_ht (if applicable),
- * - remove trigger from triggers_ht
- *
- * 5) Reception of a channel monitor sample from the consumer daemon
- * - evaluate the conditions associated with the triggers found in
- * the channel_triggers_ht,
- * - if a condition evaluates to "true" and the condition is of type
- * "notify", query the notification_trigger_clients_ht and send
- * a notification to the clients.
- *
- * 6) Connection of a client
- * - add client socket to the client_socket_ht.
- *
- * 7) Disconnection of a client
- * - remove client socket from the client_socket_ht,
- * - traverse all conditions to which the client is subscribed and remove
- * the client from the notification_trigger_clients_ht.
- *
- * 8) Subscription of a client to a condition's notifications
- * - Add the condition to the client's list of subscribed conditions,
- * - Look-up notification_trigger_clients_ht and add the client to
- * list of clients.
- *
- * 9) Unsubscription of a client to a condition's notifications
- * - Remove the condition from the client's list of subscribed conditions,
- * - Look-up notification_trigger_clients_ht and remove the client
- * from the list of clients.
- */
-
/*
* Destroy the thread data previously created by the init function.
*/
struct notification_thread_handle *handle)
{
int ret;
- struct notification_thread_command *cmd, *tmp;
if (!handle) {
goto end;
}
- if (handle->cmd_queue.event_fd < 0) {
- goto end;
- }
- ret = close(handle->cmd_queue.event_fd);
- if (ret < 0) {
- PERROR("close notification command queue event_fd");
- }
-
- pthread_mutex_lock(&handle->cmd_queue.lock);
- /* Purge queue of in-flight commands and mark them as cancelled. */
- cds_list_for_each_entry_safe(cmd, tmp, &handle->cmd_queue.list,
- cmd_list_node) {
- cds_list_del(&cmd->cmd_list_node);
- cmd->reply_code = LTTNG_ERR_COMMAND_CANCELLED;
- futex_nto1_wake(&cmd->reply_futex);
- }
- pthread_mutex_unlock(&handle->cmd_queue.lock);
+ assert(cds_list_empty(&handle->cmd_queue.list));
pthread_mutex_destroy(&handle->cmd_queue.lock);
+ if (handle->cmd_queue.event_pipe) {
+ lttng_pipe_destroy(handle->cmd_queue.event_pipe);
+ }
if (handle->channel_monitoring_pipes.ust32_consumer >= 0) {
ret = close(handle->channel_monitoring_pipes.ust32_consumer);
if (ret) {
{
int ret;
struct notification_thread_handle *handle;
+ struct lttng_pipe *event_pipe = NULL;
handle = zmalloc(sizeof(*handle));
if (!handle) {
goto end;
}
- /* FIXME Replace eventfd by a pipe to support older kernels. */
- handle->cmd_queue.event_fd = eventfd(0, EFD_CLOEXEC);
- if (handle->cmd_queue.event_fd < 0) {
- PERROR("eventfd notification command queue");
+ event_pipe = lttng_pipe_open(FD_CLOEXEC);
+ if (!event_pipe) {
+ ERR("event_pipe creation");
goto error;
}
+
+ handle->cmd_queue.event_pipe = event_pipe;
+ event_pipe = NULL;
+
CDS_INIT_LIST_HEAD(&handle->cmd_queue.list);
ret = pthread_mutex_init(&handle->cmd_queue.lock, NULL);
if (ret) {
end:
return handle;
error:
+ lttng_pipe_destroy(event_pipe);
notification_thread_handle_destroy(handle);
return NULL;
}
if (getuid() == 0) {
ret = chown(sock_path, 0,
- utils_get_group_id(tracing_group_name));
+ utils_get_group_id(config.tracing_group_name.value));
if (ret) {
ERR("Failed to set the notification channel socket's group");
ret = -1;
ERR("[notification-thread] Failed to add notification channel socket to pollset");
goto error;
}
- ret = lttng_poll_add(poll_set, handle->cmd_queue.event_fd,
+ ret = lttng_poll_add(poll_set, lttng_pipe_get_readfd(handle->cmd_queue.event_pipe),
LPOLLIN | LPOLLERR);
if (ret < 0) {
ERR("[notification-thread] Failed to add notification command queue event fd to pollset");
assert(!ret);
}
if (state->channels_ht) {
- ret = cds_lfht_destroy(state->channels_ht,
- NULL);
+ ret = cds_lfht_destroy(state->channels_ht, NULL);
+ assert(!ret);
+ }
+ if (state->sessions_ht) {
+ ret = cds_lfht_destroy(state->sessions_ht, NULL);
assert(!ret);
}
-
if (state->notification_channel_socket >= 0) {
notification_channel_socket_destroy(
state->notification_channel_socket);
if (!state->channels_ht) {
goto error;
}
-
+ state->sessions_ht = cds_lfht_new(DEFAULT_HT_SIZE,
+ 1, 0, CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL);
+ if (!state->sessions_ht) {
+ goto error;
+ }
state->triggers_ht = cds_lfht_new(DEFAULT_HT_SIZE,
1, 0, CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL);
if (!state->triggers_ht) {
ret = handle_notification_thread_channel_sample(
state, fd, domain);
if (ret) {
- ERR("[notification-thread] Consumer sample handling error occured");
+ ERR("[notification-thread] Consumer sample handling error occurred");
ret = -1;
goto end;
}
int fd = LTTNG_POLL_GETFD(&state.events, i);
uint32_t revents = LTTNG_POLL_GETEV(&state.events, i);
+ if (!revents) {
+ continue;
+ }
DBG("[notification-thread] Handling fd (%i) activity (%u)", fd, revents);
if (fd == state.notification_channel_socket) {
ERR("[notification-thread] Unexpected poll events %u for notification socket %i", revents, fd);
goto error;
}
- } else if (fd == handle->cmd_queue.event_fd) {
+ } else if (fd == lttng_pipe_get_readfd(handle->cmd_queue.event_pipe)) {
ret = handle_notification_thread_command(handle,
&state);
if (ret < 0) {
projects / lttng-tools.git / blobdiff