#include <common/utils.h>
#include <common/daemonize.h>
#include <common/config/session-config.h>
+#include <common/dynamic-buffer.h>
+#include <lttng/userspace-probe-internal.h>
+#include <lttng/event-internal.h>
#include "lttng-sessiond.h"
#include "buffer-registry.h"
#include "load-session-thread.h"
#include "notification-thread.h"
#include "notification-thread-commands.h"
-#include "syscall.h"
+#include "rotation-thread.h"
+#include "lttng-syscall.h"
#include "agent.h"
#include "ht-cleanup.h"
#include "sessiond-config.h"
+#include "timer.h"
static const char *help_msg =
#ifdef LTTNG_EMBED_HELP
/* Set to 1 when a SIGUSR1 signal is received. */
static int recv_child_signal;
+static struct lttng_kernel_tracer_version kernel_tracer_version;
+static struct lttng_kernel_tracer_abi_version kernel_tracer_abi_version;
+
/*
* Consumer daemon specific control data. Every value not initialized here is
* set to 0 by the static definition.
static pthread_t agent_reg_thread;
static pthread_t load_session_thread;
static pthread_t notification_thread;
+static pthread_t rotation_thread;
+static pthread_t timer_thread;
/*
* UST registration command queue. This queue is tied with a futex and uses a N
/* Notification thread handle. */
struct notification_thread_handle *notification_thread_handle;
+/* Rotation thread handle. */
+struct rotation_thread_handle *rotation_thread_handle;
+
/* Global hash tables */
struct lttng_ht *agent_apps_ht_by_sock = NULL;
/*
- * Whether sessiond is ready for commands/notification channel/health check
+ * The initialization of the session daemon is done in multiple phases.
+ *
+ * While all threads are launched near-simultaneously, only some of them
+ * are needed to ensure the session daemon can start to respond to client
* requests.
- * NR_LTTNG_SESSIOND_READY must match the number of calls to
- * sessiond_notify_ready().
+ *
+ * There are two important guarantees that we wish to offer with respect
+ * to the initialisation of the session daemon:
+ * - When the daemonize/background launcher process exits, the sessiond
+ * is fully able to respond to client requests,
+ * - Auto-loaded sessions are visible to clients.
+ *
+ * In order to achieve this, a number of support threads have to be launched
+ * to allow the "client" thread to function properly. Moreover, since the
+ * "load session" thread needs the client thread, we must provide a way
+ * for the "load session" thread to know that the "client" thread is up
+ * and running.
+ *
+ * Hence, the support threads decrement the lttng_sessiond_ready counter
+ * while the "client" threads waits for it to reach 0. Once the "client" thread
+ * unblocks, it posts the message_thread_ready semaphore which allows the
+ * "load session" thread to progress.
+ *
+ * This implies that the "load session" thread is the last to be initialized
+ * and will explicitly call sessiond_signal_parents(), which signals the parents
+ * that the session daemon is fully initialized.
+ *
+ * The four (4) support threads are:
+ * - agent_thread
+ * - notification_thread
+ * - rotation_thread
+ * - health_thread
*/
-#define NR_LTTNG_SESSIOND_READY 4
-int lttng_sessiond_ready = NR_LTTNG_SESSIOND_READY;
+#define NR_LTTNG_SESSIOND_SUPPORT_THREADS 4
+int lttng_sessiond_ready = NR_LTTNG_SESSIOND_SUPPORT_THREADS;
int sessiond_check_thread_quit_pipe(int fd, uint32_t events)
{
/* Notify parents that we are ready for cmd and health check */
LTTNG_HIDDEN
-void sessiond_notify_ready(void)
+void sessiond_signal_parents(void)
{
- if (uatomic_sub_return(<tng_sessiond_ready, 1) == 0) {
- /*
- * Notify parent pid that we are ready to accept command
- * for client side. This ppid is the one from the
- * external process that spawned us.
- */
- if (config.sig_parent) {
- kill(ppid, SIGUSR1);
- }
+ /*
+ * Notify parent pid that we are ready to accept command
+ * for client side. This ppid is the one from the
+ * external process that spawned us.
+ */
+ if (config.sig_parent) {
+ kill(ppid, SIGUSR1);
+ }
- /*
- * Notify the parent of the fork() process that we are
- * ready.
- */
- if (config.daemonize || config.background) {
- kill(child_ppid, SIGUSR1);
- }
+ /*
+ * Notify the parent of the fork() process that we are
+ * ready.
+ */
+ if (config.daemonize || config.background) {
+ kill(child_ppid, SIGUSR1);
}
}
+LTTNG_HIDDEN
+void sessiond_notify_ready(void)
+{
+ /*
+ * This memory barrier is paired with the one performed by
+ * the client thread after it has seen that 'lttng_sessiond_ready' is 0.
+ *
+ * The purpose of these memory barriers is to ensure that all
+ * initialization operations of the various threads that call this
+ * function to signal that they are ready are commited/published
+ * before the client thread can see the 'lttng_sessiond_ready' counter
+ * reach 0.
+ *
+ * Note that this could be a 'write' memory barrier, but a full barrier
+ * is used in case the code using this utility changes. The performance
+ * implications of this choice are minimal since this is a slow path.
+ */
+ cmm_smp_mb();
+ uatomic_sub(<tng_sessiond_ready, 1);
+}
+
static
int __sessiond_set_thread_pollset(struct lttng_poll_event *events, size_t size,
int *a_pipe)
*/
utils_close_pipe(thread_quit_pipe);
- /*
- * If config.pid_file_path.value is undefined, the default file will be
- * wiped when removing the rundir.
- */
- if (config.pid_file_path.value) {
- ret = remove(config.pid_file_path.value);
- if (ret < 0) {
- PERROR("remove pidfile %s", config.pid_file_path.value);
- }
+ ret = remove(config.pid_file_path.value);
+ if (ret < 0) {
+ PERROR("remove pidfile %s", config.pid_file_path.value);
}
DBG("Removing sessiond and consumerd content of directory %s",
/* Cleanup ALL session */
cds_list_for_each_entry_safe(sess, stmp,
&session_list_ptr->head, list) {
- cmd_destroy_session(sess, kernel_poll_pipe[1]);
+ cmd_destroy_session(sess, kernel_poll_pipe[1],
+ notification_thread_handle);
}
}
free(load_info);
}
- /*
- * Cleanup lock file by deleting it and finaly closing it which will
- * release the file system lock.
- */
- if (lockfile_fd >= 0) {
- ret = remove(config.lock_file_path.value);
- if (ret < 0) {
- PERROR("remove lock file");
- }
- ret = close(lockfile_fd);
- if (ret < 0) {
- PERROR("close lock file");
- }
- }
-
/*
* We do NOT rmdir rundir because there are other processes
* using it, for instance lttng-relayd, which can start in
*
* Useful for CPU hotplug feature.
*/
-static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
+static int update_kernel_stream(int fd)
{
int ret = 0;
struct ltt_session *session;
cds_lfht_for_each_entry(ksess->consumer->socks->ht,
&iter.iter, socket, node.node) {
pthread_mutex_lock(socket->lock);
- ret = kernel_consumer_send_channel_stream(socket,
+ ret = kernel_consumer_send_channel_streams(socket,
channel, ksess,
session->output_traces ? 1 : 0);
pthread_mutex_unlock(socket->lock);
* New CPU detected by the kernel. Adding kernel stream to
* kernel session and updating the kernel consumer
*/
- ret = update_kernel_stream(&kconsumer_data, pollfd);
+ ret = update_kernel_stream(pollfd);
if (ret < 0) {
continue;
}
health_code_update();
/*
- * Transfer the write-end of the channel monitoring pipe to the
- * by issuing a SET_CHANNEL_MONITOR_PIPE command.
+ * Transfer the write-end of the channel monitoring and rotate pipe
+ * to the consumer by issuing a SET_CHANNEL_MONITOR_PIPE command.
*/
cmd_socket_wrapper = consumer_allocate_socket(&consumer_data->cmd_sock);
if (!cmd_socket_wrapper) {
if (ret) {
goto error;
}
+
/* Discard the socket wrapper as it is no longer needed. */
consumer_destroy_socket(cmd_socket_wrapper);
cmd_socket_wrapper = NULL;
} else if (stat(INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE, &st) == 0) {
DBG3("Found location #2");
consumer_to_use = INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE;
- } else if (stat(config.consumerd32_bin_path.value, &st) == 0) {
+ } else if (config.consumerd32_bin_path.value &&
+ stat(config.consumerd32_bin_path.value, &st) == 0) {
DBG3("Found location #3");
consumer_to_use = config.consumerd32_bin_path.value;
} else {
}
/* Validate kernel version */
- ret = kernel_validate_version(kernel_tracer_fd);
+ ret = kernel_validate_version(kernel_tracer_fd, &kernel_tracer_version,
+ &kernel_tracer_abi_version);
if (ret < 0) {
goto error_version;
}
goto error;
}
- /* Create directory(ies) on local filesystem. */
- if (session->kernel_session->consumer->type == CONSUMER_DST_LOCAL &&
- strlen(session->kernel_session->consumer->dst.trace_path) > 0) {
- ret = run_as_mkdir_recursive(
- session->kernel_session->consumer->dst.trace_path,
- S_IRWXU | S_IRWXG, session->uid, session->gid);
- if (ret < 0) {
- if (errno != EEXIST) {
- ERR("Trace directory creation error");
- goto error;
- }
- }
- }
-
session->kernel_session->uid = session->uid;
session->kernel_session->gid = session->gid;
session->kernel_session->output_traces = session->output_traces;
return i;
}
+static int receive_userspace_probe(struct command_ctx *cmd_ctx, int sock,
+ int *sock_error, struct lttng_event *event)
+{
+ int fd, ret;
+ struct lttng_userspace_probe_location *probe_location;
+ const struct lttng_userspace_probe_location_lookup_method *lookup = NULL;
+ struct lttng_dynamic_buffer probe_location_buffer;
+ struct lttng_buffer_view buffer_view;
+
+ /*
+ * Create a buffer to store the serialized version of the probe
+ * location.
+ */
+ lttng_dynamic_buffer_init(&probe_location_buffer);
+ ret = lttng_dynamic_buffer_set_size(&probe_location_buffer,
+ cmd_ctx->lsm->u.enable.userspace_probe_location_len);
+ if (ret) {
+ ret = LTTNG_ERR_NOMEM;
+ goto error;
+ }
+
+ /*
+ * Receive the probe location.
+ */
+ ret = lttcomm_recv_unix_sock(sock, probe_location_buffer.data,
+ probe_location_buffer.size);
+ if (ret <= 0) {
+ DBG("Nothing recv() from client var len data... continuing");
+ *sock_error = 1;
+ lttng_dynamic_buffer_reset(&probe_location_buffer);
+ ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto error;
+ }
+
+ buffer_view = lttng_buffer_view_from_dynamic_buffer(
+ &probe_location_buffer, 0, probe_location_buffer.size);
+
+ /*
+ * Extract the probe location from the serialized version.
+ */
+ ret = lttng_userspace_probe_location_create_from_buffer(
+ &buffer_view, &probe_location);
+ if (ret < 0) {
+ WARN("Failed to create a userspace probe location from the received buffer");
+ lttng_dynamic_buffer_reset( &probe_location_buffer);
+ ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto error;
+ }
+
+ /*
+ * Receive the file descriptor to the target binary from the client.
+ */
+ DBG("Receiving userspace probe target FD from client ...");
+ ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1);
+ if (ret <= 0) {
+ DBG("Nothing recv() from client userspace probe fd... continuing");
+ *sock_error = 1;
+ ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto error;
+ }
+
+ /*
+ * Set the file descriptor received from the client through the unix
+ * socket in the probe location.
+ */
+ lookup = lttng_userspace_probe_location_get_lookup_method(probe_location);
+ if (!lookup) {
+ ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto error;
+ }
+
+ /*
+ * From the kernel tracer's perspective, all userspace probe event types
+ * are all the same: a file and an offset.
+ */
+ switch (lttng_userspace_probe_location_lookup_method_get_type(lookup)) {
+ case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF:
+ ret = lttng_userspace_probe_location_function_set_binary_fd(
+ probe_location, fd);
+ break;
+ case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT:
+ ret = lttng_userspace_probe_location_tracepoint_set_binary_fd(
+ probe_location, fd);
+ break;
+ default:
+ ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto error;
+ }
+
+ if (ret) {
+ ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto error;
+ }
+
+ /* Attach the probe location to the event. */
+ ret = lttng_event_set_userspace_probe_location(event, probe_location);
+ if (ret) {
+ ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
+ goto error;
+ }
+
+ lttng_dynamic_buffer_reset(&probe_location_buffer);
+error:
+ return ret;
+}
+
+/*
+ * Check if the current kernel tracer supports the session rotation feature.
+ * Return 1 if it does, 0 otherwise.
+ */
+static int check_rotate_compatible(void)
+{
+ int ret = 1;
+
+ if (kernel_tracer_version.major != 2 || kernel_tracer_version.minor < 11) {
+ DBG("Kernel tracer version is not compatible with the rotation feature");
+ ret = 0;
+ }
+
+ return ret;
+}
+
/*
* Process the command requested by the lttng client within the command
* context structure. This function make sure that the return structure (llm)
case LTTNG_REGENERATE_STATEDUMP:
case LTTNG_REGISTER_TRIGGER:
case LTTNG_UNREGISTER_TRIGGER:
+ case LTTNG_ROTATE_SESSION:
+ case LTTNG_ROTATION_GET_INFO:
+ case LTTNG_ROTATION_SET_SCHEDULE:
+ case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
need_domain = 0;
break;
default:
case LTTNG_LIST_SYSCALLS:
case LTTNG_LIST_TRACKER_PIDS:
case LTTNG_DATA_PENDING:
+ case LTTNG_ROTATE_SESSION:
+ case LTTNG_ROTATION_GET_INFO:
+ case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
break;
default:
/* Setup lttng message with no payload */
}
/*
- * Setup socket for consumer 64 bit. No need for atomic access
+ * Setup socket for consumer 32 bit. No need for atomic access
* since it was set above and can ONLY be set in this thread.
*/
ret = consumer_create_socket(&ustconsumer32_data,
}
case LTTNG_ENABLE_EVENT:
{
+ struct lttng_event *ev = NULL;
struct lttng_event_exclusion *exclusion = NULL;
struct lttng_filter_bytecode *bytecode = NULL;
char *filter_expression = NULL;
ret = lttcomm_recv_unix_sock(sock, filter_expression,
expression_len);
if (ret <= 0) {
- DBG("Nothing recv() from client car len data... continuing");
+ DBG("Nothing recv() from client var len data... continuing");
*sock_error = 1;
free(filter_expression);
free(exclusion);
DBG("Receiving var len filter's bytecode from client ...");
ret = lttcomm_recv_unix_sock(sock, bytecode, bytecode_len);
if (ret <= 0) {
- DBG("Nothing recv() from client car len data... continuing");
+ DBG("Nothing recv() from client var len data... continuing");
*sock_error = 1;
free(filter_expression);
free(bytecode);
}
}
+ ev = lttng_event_copy(&cmd_ctx->lsm->u.enable.event);
+ if (!ev) {
+ DBG("Failed to copy event: %s",
+ cmd_ctx->lsm->u.enable.event.name);
+ free(filter_expression);
+ free(bytecode);
+ free(exclusion);
+ ret = LTTNG_ERR_NOMEM;
+ goto error;
+ }
+
+
+ if (cmd_ctx->lsm->u.enable.userspace_probe_location_len > 0) {
+ /* Expect a userspace probe description. */
+ ret = receive_userspace_probe(cmd_ctx, sock, sock_error, ev);
+ if (ret) {
+ free(filter_expression);
+ free(bytecode);
+ free(exclusion);
+ lttng_event_destroy(ev);
+ goto error;
+ }
+ }
+
ret = cmd_enable_event(cmd_ctx->session, &cmd_ctx->lsm->domain,
cmd_ctx->lsm->u.enable.channel_name,
- &cmd_ctx->lsm->u.enable.event,
+ ev,
filter_expression, bytecode, exclusion,
kernel_poll_pipe[1]);
+ lttng_event_destroy(ev);
break;
}
case LTTNG_LIST_TRACEPOINTS:
}
case LTTNG_START_TRACE:
{
+ /*
+ * On the first start, if we have a kernel session and we have
+ * enabled time or size-based rotations, we have to make sure
+ * the kernel tracer supports it.
+ */
+ if (!cmd_ctx->session->has_been_started && \
+ cmd_ctx->session->kernel_session && \
+ (cmd_ctx->session->rotate_timer_period || \
+ cmd_ctx->session->rotate_size) && \
+ !check_rotate_compatible()) {
+ DBG("Kernel tracer version is not compatible with the rotation feature");
+ ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
+ goto error;
+ }
ret = cmd_start_trace(cmd_ctx->session);
break;
}
}
case LTTNG_DESTROY_SESSION:
{
- ret = cmd_destroy_session(cmd_ctx->session, kernel_poll_pipe[1]);
+ ret = cmd_destroy_session(cmd_ctx->session, kernel_poll_pipe[1],
+ notification_thread_handle);
/* Set session to NULL so we do not unlock it after free. */
cmd_ctx->session = NULL;
notification_thread_handle);
break;
}
+ case LTTNG_ROTATE_SESSION:
+ {
+ struct lttng_rotate_session_return rotate_return;
+
+ DBG("Client rotate session \"%s\"", cmd_ctx->session->name);
+
+ memset(&rotate_return, 0, sizeof(rotate_return));
+ if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) {
+ DBG("Kernel tracer version is not compatible with the rotation feature");
+ ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
+ goto error;
+ }
+
+ ret = cmd_rotate_session(cmd_ctx->session, &rotate_return);
+ if (ret < 0) {
+ ret = -ret;
+ goto error;
+ }
+
+ ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &rotate_return,
+ sizeof(rotate_return));
+ if (ret < 0) {
+ ret = -ret;
+ goto error;
+ }
+
+ ret = LTTNG_OK;
+ break;
+ }
+ case LTTNG_ROTATION_GET_INFO:
+ {
+ struct lttng_rotation_get_info_return get_info_return;
+
+ memset(&get_info_return, 0, sizeof(get_info_return));
+ ret = cmd_rotate_get_info(cmd_ctx->session, &get_info_return,
+ cmd_ctx->lsm->u.get_rotation_info.rotation_id);
+ if (ret < 0) {
+ ret = -ret;
+ goto error;
+ }
+
+ ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &get_info_return,
+ sizeof(get_info_return));
+ if (ret < 0) {
+ ret = -ret;
+ goto error;
+ }
+
+ ret = LTTNG_OK;
+ break;
+ }
+ case LTTNG_ROTATION_SET_SCHEDULE:
+ {
+ bool set_schedule;
+ enum lttng_rotation_schedule_type schedule_type;
+ uint64_t value;
+
+ if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) {
+ DBG("Kernel tracer version does not support session rotations");
+ ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
+ goto error;
+ }
+
+ set_schedule = cmd_ctx->lsm->u.rotation_set_schedule.set == 1;
+ schedule_type = (enum lttng_rotation_schedule_type) cmd_ctx->lsm->u.rotation_set_schedule.type;
+ value = cmd_ctx->lsm->u.rotation_set_schedule.value;
+
+ ret = cmd_rotation_set_schedule(cmd_ctx->session,
+ set_schedule,
+ schedule_type,
+ value,
+ notification_thread_handle);
+ if (ret != LTTNG_OK) {
+ goto error;
+ }
+
+ break;
+ }
+ case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
+ {
+ struct lttng_session_list_schedules_return schedules = {
+ .periodic.set = !!cmd_ctx->session->rotate_timer_period,
+ .periodic.value = cmd_ctx->session->rotate_timer_period,
+ .size.set = !!cmd_ctx->session->rotate_size,
+ .size.value = cmd_ctx->session->rotate_size,
+ };
+
+ ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &schedules,
+ sizeof(schedules));
+ if (ret < 0) {
+ ret = -ret;
+ goto error;
+ }
+
+ ret = LTTNG_OK;
+ break;
+ }
default:
ret = LTTNG_ERR_UND;
break;
goto error;
}
- sessiond_notify_ready();
ret = sem_post(&load_info->message_thread_ready);
if (ret) {
PERROR("sem_post message_thread_ready");
goto error;
}
+ /*
+ * Wait until all support threads are initialized before accepting
+ * commands.
+ */
+ while (uatomic_read(<tng_sessiond_ready) != 0) {
+ fd_set read_fds;
+ struct timeval timeout;
+
+ FD_ZERO(&read_fds);
+ FD_SET(thread_quit_pipe[0], &read_fds);
+ memset(&timeout, 0, sizeof(timeout));
+ timeout.tv_usec = 1000;
+
+ /*
+ * If a support thread failed to launch, it may signal that
+ * we must exit and the sessiond would never be marked as
+ * "ready".
+ *
+ * The timeout is set to 1ms, which serves as a way to
+ * pace down this check.
+ */
+ ret = select(thread_quit_pipe[0] + 1, &read_fds, NULL, NULL,
+ &timeout);
+ if (ret > 0 || (ret < 0 && errno != EINTR)) {
+ goto exit;
+ }
+ }
+ /*
+ * This barrier is paired with the one in sessiond_notify_ready() to
+ * ensure that loads accessing data initialized by the other threads,
+ * on which this thread was waiting, are not performed before this point.
+ *
+ * Note that this could be a 'read' memory barrier, but a full barrier
+ * is used in case the code changes. The performance implications of
+ * this choice are minimal since this is a slow path.
+ */
+ cmm_smp_mb();
+
/* This testpoint is after we signal readiness to the parent. */
if (testpoint(sessiond_thread_manage_clients)) {
goto error;
health_code_update();
while (1) {
+ const struct cmd_completion_handler *cmd_completion_handler;
+
DBG("Accepting client command ...");
/* Inifinite blocking call, waiting for transmission */
continue;
}
+ cmd_completion_handler = cmd_pop_completion_handler();
+ if (cmd_completion_handler) {
+ enum lttng_error_code completion_code;
+
+ completion_code = cmd_completion_handler->run(
+ cmd_completion_handler->data);
+ if (completion_code != LTTNG_OK) {
+ clean_command_ctx(&cmd_ctx);
+ continue;
+ }
+ }
+
health_code_update();
DBG("Sending response (size: %d, retcode: %s (%d))",
} else if (string_match(optname, "no-kernel")) {
config.no_kernel = true;
} else if (string_match(optname, "quiet") || opt == 'q') {
- lttng_opt_quiet = true;
+ config.quiet = true;
} else if (string_match(optname, "verbose") || opt == 'v') {
/* Verbose level can increase using multiple -v */
if (arg) {
ERR("Port overflow in --agent-tcp-port parameter: %s", arg);
return -1;
}
- config.agent_tcp_port = (uint32_t) v;
- DBG3("Agent TCP port set to non default: %u", config.agent_tcp_port);
+ config.agent_tcp_port.begin = config.agent_tcp_port.end = (int) v;
+ DBG3("Agent TCP port set to non default: %i", (int) v);
}
} else if (string_match(optname, "load") || opt == 'l') {
if (!arg || *arg == '\0') {
return ret;
}
+/*
+ * Create lockfile using the rundir and return its fd.
+ */
+static int create_lockfile(void)
+{
+ return utils_create_lock_file(config.lock_file_path.value);
+}
+
/*
* Check if the global socket is available, and if a daemon is answering at the
* other side. If yes, error is returned.
+ *
+ * Also attempts to create and hold the lock file.
*/
static int check_existing_daemon(void)
{
+ int ret = 0;
+
/* Is there anybody out there ? */
if (lttng_session_daemon_alive()) {
- return -EEXIST;
+ ret = -EEXIST;
+ goto end;
}
- return 0;
+ lockfile_fd = create_lockfile();
+ if (lockfile_fd < 0) {
+ ret = -EEXIST;
+ goto end;
+ }
+end:
+ return ret;
+}
+
+static void sessiond_cleanup_lock_file(void)
+{
+ int ret;
+
+ /*
+ * Cleanup lock file by deleting it and finaly closing it which will
+ * release the file system lock.
+ */
+ if (lockfile_fd >= 0) {
+ ret = remove(config.lock_file_path.value);
+ if (ret < 0) {
+ PERROR("remove lock file");
+ }
+ ret = close(lockfile_fd);
+ if (ret < 0) {
+ PERROR("close lock file");
+ }
+ }
}
/*
return utils_create_pid_file(getpid(), config.pid_file_path.value);
}
-/*
- * Create lockfile using the rundir and return its fd.
- */
-static int create_lockfile(void)
-{
- return utils_create_lock_file(config.lock_file_path.value);
-}
-
-/*
- * Write agent TCP port using the rundir.
- */
-static int write_agent_port(void)
-{
- return utils_create_pid_file(config.agent_tcp_port,
- config.agent_port_file_path.value);
-}
-
static int set_clock_plugin_env(void)
{
int ret = 0;
struct lttng_pipe *ust32_channel_monitor_pipe = NULL,
*ust64_channel_monitor_pipe = NULL,
*kernel_channel_monitor_pipe = NULL;
- bool notification_thread_running = false;
+ bool notification_thread_launched = false;
+ bool rotation_thread_launched = false;
+ bool timer_thread_launched = false;
+ struct timer_thread_parameters timer_thread_ctx;
+ /* Queue of rotation jobs populated by the sessiond-timer. */
+ struct rotation_thread_timer_queue *rotation_timer_queue = NULL;
+ sem_t notification_thread_ready;
init_kernel_workarounds();
goto exit_set_signal_handler;
}
+ if (timer_signal_init()) {
+ retval = -1;
+ goto exit_set_signal_handler;
+ }
+
page_size = sysconf(_SC_PAGESIZE);
if (page_size < 0) {
PERROR("sysconf _SC_PAGESIZE");
goto exit_set_signal_handler;
}
+ /*
+ * Init config from environment variables.
+ * Command line option override env configuration per-doc. Do env first.
+ */
+ sessiond_config_apply_env_config(&config);
+
/*
* Parse arguments and load the daemon configuration file.
*
goto exit_options;
}
- /* Init config from environment variables. */
- sessiond_config_apply_env_config(&config);
-
/*
* Resolve all paths received as arguments, configuration option, or
* through environment variable as absolute paths. This is necessary
sessiond_config_log(&config);
+ if (create_lttng_rundir()) {
+ retval = -1;
+ goto exit_options;
+ }
+
+ /* Abort launch if a session daemon is already running. */
+ if (check_existing_daemon()) {
+ ERR("A session daemon is already running.");
+ retval = -1;
+ goto exit_options;
+ }
+
/* Daemonize */
if (config.daemonize || config.background) {
int i;
/*
* We are in the child. Make sure all other file descriptors are
* closed, in case we are called with more opened file
- * descriptors than the standard ones.
+ * descriptors than the standard ones and the lock file.
*/
for (i = 3; i < sysconf(_SC_OPEN_MAX); i++) {
+ if (i == lockfile_fd) {
+ continue;
+ }
(void) close(i);
}
}
/* Check if daemon is UID = 0 */
is_root = !getuid();
-
- if (create_lttng_rundir()) {
- retval = -1;
- goto exit_init_data;
- }
-
if (is_root) {
/* Create global run dir with root access */
}
}
- lockfile_fd = create_lockfile();
- if (lockfile_fd < 0) {
- retval = -1;
- goto exit_init_data;
- }
-
/* Set consumer initial state */
kernel_consumerd_state = CONSUMER_STOPPED;
ust_consumerd_state = CONSUMER_STOPPED;
goto exit_init_data;
}
+ /*
+ * The rotation_thread_timer_queue structure is shared between the
+ * sessiond timer thread and the rotation thread. The main thread keeps
+ * its ownership and destroys it when both threads have been joined.
+ */
+ rotation_timer_queue = rotation_thread_timer_queue_create();
+ if (!rotation_timer_queue) {
+ retval = -1;
+ goto exit_init_data;
+ }
+ timer_thread_ctx.rotation_thread_job_queue = rotation_timer_queue;
+
ust64_channel_monitor_pipe = lttng_pipe_open(0);
if (!ust64_channel_monitor_pipe) {
ERR("Failed to create 64-bit user space consumer channel monitor pipe");
goto exit_init_data;
}
- /*
- * See if daemon already exist.
- */
- if (check_existing_daemon()) {
- ERR("Already running daemon.\n");
- /*
- * We do not goto exit because we must not cleanup()
- * because a daemon is already running.
- */
- retval = -1;
- goto exit_init_data;
- }
-
/*
* Init UST app hash table. Alloc hash table before this point since
* cleanup() can get called after that point.
retval = -1;
goto exit_init_data;
}
- ret = write_agent_port();
- if (ret) {
- ERR("Error in write_agent_port");
- retval = -1;
- goto exit_init_data;
- }
/* Initialize communication library */
lttcomm_init();
goto exit_health;
}
+ /*
+ * The rotation thread needs the notification thread to be ready before
+ * creating the rotate_notification_channel, so we use this semaphore as
+ * a rendez-vous point.
+ */
+ sem_init(¬ification_thread_ready, 0, 0);
+
/* notification_thread_data acquires the pipes' read side. */
notification_thread_handle = notification_thread_handle_create(
ust32_channel_monitor_pipe,
ust64_channel_monitor_pipe,
- kernel_channel_monitor_pipe);
+ kernel_channel_monitor_pipe,
+ ¬ification_thread_ready);
if (!notification_thread_handle) {
retval = -1;
ERR("Failed to create notification thread shared data");
stop_threads();
goto exit_notification;
}
- notification_thread_running = true;
+ notification_thread_launched = true;
+
+ /* Create timer thread. */
+ ret = pthread_create(&timer_thread, default_pthread_attr(),
+ timer_thread_func, &timer_thread_ctx);
+ if (ret) {
+ errno = ret;
+ PERROR("pthread_create timer");
+ retval = -1;
+ stop_threads();
+ goto exit_notification;
+ }
+ timer_thread_launched = true;
+
+ /* rotation_thread_data acquires the pipes' read side. */
+ rotation_thread_handle = rotation_thread_handle_create(
+ thread_quit_pipe[0],
+ rotation_timer_queue,
+ notification_thread_handle,
+ ¬ification_thread_ready);
+ if (!rotation_thread_handle) {
+ retval = -1;
+ ERR("Failed to create rotation thread shared data");
+ stop_threads();
+ goto exit_rotation;
+ }
+
+ /* Create rotation thread. */
+ ret = pthread_create(&rotation_thread, default_pthread_attr(),
+ thread_rotation, rotation_thread_handle);
+ if (ret) {
+ errno = ret;
+ PERROR("pthread_create rotation");
+ retval = -1;
+ stop_threads();
+ goto exit_rotation;
+ }
+ rotation_thread_launched = true;
/* Create thread to manage the client socket */
ret = pthread_create(&client_thread, default_pthread_attr(),
}
exit_client:
+exit_rotation:
exit_notification:
+ sem_destroy(¬ification_thread_ready);
ret = pthread_join(health_thread, &status);
if (ret) {
errno = ret;
* of the active session and channels at the moment of the teardown.
*/
if (notification_thread_handle) {
- if (notification_thread_running) {
+ if (notification_thread_launched) {
notification_thread_command_quit(
notification_thread_handle);
ret = pthread_join(notification_thread, &status);
notification_thread_handle_destroy(notification_thread_handle);
}
+ if (rotation_thread_handle) {
+ if (rotation_thread_launched) {
+ ret = pthread_join(rotation_thread, &status);
+ if (ret) {
+ errno = ret;
+ PERROR("pthread_join rotation thread");
+ retval = -1;
+ }
+ }
+ rotation_thread_handle_destroy(rotation_thread_handle);
+ }
+
+ if (timer_thread_launched) {
+ timer_exit();
+ ret = pthread_join(timer_thread, &status);
+ if (ret) {
+ errno = ret;
+ PERROR("pthread_join timer thread");
+ retval = -1;
+ }
+ }
+
+ /*
+ * After the rotation and timer thread have quit, we can safely destroy
+ * the rotation_timer_queue.
+ */
+ rotation_thread_timer_queue_destroy(rotation_timer_queue);
+
rcu_thread_offline();
rcu_unregister_thread();
exit_create_run_as_worker_cleanup:
exit_options:
+ sessiond_cleanup_lock_file();
sessiond_cleanup_options();
exit_set_signal_handler:
projects / lttng-tools.git / blobdiff