/*
* Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
+ * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
*
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; only version 2 of the License.
*
- * 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.
+ * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * 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., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
-#include <sys/ipc.h>
-#include <sys/shm.h>
+#include <sys/mman.h>
+#include <sys/mount.h>
+#include <sys/resource.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
-#include <sys/time.h>
-#include <sys/resource.h>
+#include <sys/wait.h>
+#include <urcu/futex.h>
#include <unistd.h>
-#include <urcu/list.h> /* URCU list library (-lurcu) */
-#include <lttng/lttng.h>
+#include <ltt-kconsumerd.h>
+#include <lttng-sessiond-comm.h>
+#include <lttng/lttng-kconsumerd.h>
+#include <lttngerr.h>
-#include "liblttsessiondcomm.h"
-#include "ltt-sessiond.h"
-#include "lttngerr.h"
+#include "channel.h"
+#include "compat/poll.h"
+#include "context.h"
+#include "event.h"
+#include "futex.h"
#include "kernel-ctl.h"
-#include "ust-ctl.h"
-#include "session.h"
+#include "ltt-sessiond.h"
+#include "shm.h"
#include "traceable-app.h"
-#include "lttng-kconsumerd.h"
-#include "libustctl.h"
+#include "ust-ctl.h"
#include "utils.h"
-
-/*
- * TODO:
- * teardown: signal SIGTERM handler -> write into pipe. Threads waits
- * with epoll on pipe and on other pipes/sockets for commands. Main
- * simply waits on pthread join.
- */
+#include "ust-ctl.h"
/* Const values */
const char default_home_dir[] = DEFAULT_HOME_DIR;
/* Variables */
int opt_verbose; /* Not static for lttngerr.h */
+int opt_verbose_kconsumerd; /* Not static for lttngerr.h */
int opt_quiet; /* Not static for lttngerr.h */
+
const char *progname;
const char *opt_tracing_group;
static int opt_sig_parent;
static int is_root; /* Set to 1 if the daemon is running as root */
static pid_t ppid; /* Parent PID for --sig-parent option */
static pid_t kconsumerd_pid;
-
-static char apps_unix_sock_path[PATH_MAX]; /* Global application Unix socket path */
-static char client_unix_sock_path[PATH_MAX]; /* Global client Unix socket path */
-static char kconsumerd_err_unix_sock_path[PATH_MAX]; /* kconsumerd error Unix socket path */
-static char kconsumerd_cmd_unix_sock_path[PATH_MAX]; /* kconsumerd command Unix socket path */
+static int dispatch_thread_exit;
+
+/* Global application Unix socket path */
+static char apps_unix_sock_path[PATH_MAX];
+/* Global client Unix socket path */
+static char client_unix_sock_path[PATH_MAX];
+/* kconsumerd error and command Unix socket path */
+static char kconsumerd_err_unix_sock_path[PATH_MAX];
+static char kconsumerd_cmd_unix_sock_path[PATH_MAX];
+/* global wait shm path for UST */
+static char wait_shm_path[PATH_MAX];
/* Sockets and FDs */
static int client_sock;
static int kconsumerd_err_sock;
static int kconsumerd_cmd_sock;
static int kernel_tracer_fd;
+static int kernel_poll_pipe[2];
+
+/*
+ * Quit pipe for all threads. This permits a single cancellation point
+ * for all threads when receiving an event on the pipe.
+ */
+static int thread_quit_pipe[2];
+
+/*
+ * This pipe is used to inform the thread managing application communication
+ * that a command is queued and ready to be processed.
+ */
+static int apps_cmd_pipe[2];
/* Pthread, Mutexes and Semaphores */
static pthread_t kconsumerd_thread;
static pthread_t apps_thread;
+static pthread_t reg_apps_thread;
static pthread_t client_thread;
+static pthread_t kernel_thread;
+static pthread_t dispatch_thread;
static sem_t kconsumerd_sem;
-static pthread_mutex_t kconsumerd_pid_mutex; /* Mutex to control kconsumerd pid assignation */
+
+/* Mutex to control kconsumerd pid assignation */
+static pthread_mutex_t kconsumerd_pid_mutex;
+
+/*
+ * UST registration command queue. This queue is tied with a futex and uses a N
+ * wakers / 1 waiter implemented and detailed in futex.c/.h
+ *
+ * The thread_manage_apps and thread_dispatch_ust_registration interact with
+ * this queue and the wait/wake scheme.
+ */
+static struct ust_cmd_queue ust_cmd_queue;
+
+/*
+ * Pointer initialized before thread creation.
+ *
+ * This points to the tracing session list containing the session count and a
+ * mutex lock. The lock MUST be taken if you iterate over the list. The lock
+ * MUST NOT be taken if you call a public function in session.c.
+ *
+ * The lock is nested inside the structure: session_list_ptr->lock. Please use
+ * session_lock_list and session_unlock_list for lock acquisition.
+ */
+static struct ltt_session_list *session_list_ptr;
+
+/*
+ * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
+ */
+static int create_thread_poll_set(struct lttng_poll_event *events,
+ unsigned int size)
+{
+ int ret;
+
+ if (events == NULL || size == 0) {
+ ret = -1;
+ goto error;
+ }
+
+ ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
+ if (ret < 0) {
+ goto error;
+ }
+
+ /* Add quit pipe */
+ ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
+ if (ret < 0) {
+ goto error;
+ }
+
+ return 0;
+
+error:
+ return ret;
+}
+
+/*
+ * Check if the thread quit pipe was triggered.
+ *
+ * Return 1 if it was triggered else 0;
+ */
+static int check_thread_quit_pipe(int fd, uint32_t events)
+{
+ if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
+ return 1;
+ }
+
+ return 0;
+}
+
+/*
+ * Remove modules in reverse load order.
+ */
+static int modprobe_remove_kernel_modules(void)
+{
+ int ret = 0, i;
+ char modprobe[256];
+
+ for (i = ARRAY_SIZE(kernel_modules_list) - 1; i >= 0; i--) {
+ ret = snprintf(modprobe, sizeof(modprobe),
+ "/sbin/modprobe --remove --quiet %s",
+ kernel_modules_list[i].name);
+ if (ret < 0) {
+ perror("snprintf modprobe --remove");
+ goto error;
+ }
+ modprobe[sizeof(modprobe) - 1] = '\0';
+ ret = system(modprobe);
+ if (ret == -1) {
+ ERR("Unable to launch modprobe --remove for module %s",
+ kernel_modules_list[i].name);
+ } else if (kernel_modules_list[i].required
+ && WEXITSTATUS(ret) != 0) {
+ ERR("Unable to remove module %s",
+ kernel_modules_list[i].name);
+ } else {
+ DBG("Modprobe removal successful %s",
+ kernel_modules_list[i].name);
+ }
+ }
+
+error:
+ return ret;
+}
+
+/*
+ * Return group ID of the tracing group or -1 if not found.
+ */
+static gid_t allowed_group(void)
+{
+ struct group *grp;
+
+ if (opt_tracing_group) {
+ grp = getgrnam(opt_tracing_group);
+ } else {
+ grp = getgrnam(default_tracing_group);
+ }
+ if (!grp) {
+ return -1;
+ } else {
+ return grp->gr_gid;
+ }
+}
/*
- * teardown_kernel_session
+ * Init thread quit pipe.
*
- * Complete teardown of a kernel session. This free all data structure
- * related to a kernel session and update counter.
+ * Return -1 on error or 0 if all pipes are created.
+ */
+static int init_thread_quit_pipe(void)
+{
+ int ret;
+
+ ret = pipe2(thread_quit_pipe, O_CLOEXEC);
+ if (ret < 0) {
+ perror("thread quit pipe");
+ goto error;
+ }
+
+error:
+ return ret;
+}
+
+/*
+ * Complete teardown of a kernel session. This free all data structure related
+ * to a kernel session and update counter.
*/
static void teardown_kernel_session(struct ltt_session *session)
{
if (session->kernel_session != NULL) {
DBG("Tearing down kernel session");
- trace_destroy_kernel_session(session->kernel_session);
+
+ /*
+ * If a custom kernel consumer was registered, close the socket before
+ * tearing down the complete kernel session structure
+ */
+ if (session->kernel_session->consumer_fd != kconsumerd_cmd_sock) {
+ lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
+ }
+
+ trace_kernel_destroy_session(session->kernel_session);
/* Extra precaution */
session->kernel_session = NULL;
- /* Decrement session count */
- session->kern_session_count--;
}
}
/*
- * cleanup
- *
- * Cleanup the daemon on exit
+ * Stop all threads by closing the thread quit pipe.
+ */
+static void stop_threads(void)
+{
+ int ret;
+
+ /* Stopping all threads */
+ DBG("Terminating all threads");
+ ret = notify_thread_pipe(thread_quit_pipe[1]);
+ if (ret < 0) {
+ ERR("write error on thread quit pipe");
+ }
+
+ /* Dispatch thread */
+ dispatch_thread_exit = 1;
+ futex_nto1_wake(&ust_cmd_queue.futex);
+}
+
+/*
+ * Cleanup the daemon
*/
-static void cleanup()
+static void cleanup(void)
{
int ret;
char *cmd;
- struct ltt_session *sess;
+ struct ltt_session *sess, *stmp;
DBG("Cleaning up");
/* <fun> */
- MSG("\n%c[%d;%dm*** assert failed *** ==> %c[%dm", 27,1,31,27,0);
- MSG("%c[%d;%dmMatthew, BEET driven development works!%c[%dm",27,1,33,27,0);
+ MSG("%c[%d;%dm*** assert failed *** ==> %c[%dm%c[%d;%dm"
+ "Matthew, BEET driven development works!%c[%dm",
+ 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
/* </fun> */
- /* Stopping all threads */
- DBG("Terminating all threads");
- pthread_cancel(client_thread);
- pthread_cancel(apps_thread);
- if (kconsumerd_pid != 0) {
- pthread_cancel(kconsumerd_thread);
+ if (is_root) {
+ DBG("Removing %s directory", LTTNG_RUNDIR);
+ ret = asprintf(&cmd, "rm -rf " LTTNG_RUNDIR);
+ if (ret < 0) {
+ ERR("asprintf failed. Something is really wrong!");
+ }
+
+ /* Remove lttng run directory */
+ ret = system(cmd);
+ if (ret < 0) {
+ ERR("Unable to clean " LTTNG_RUNDIR);
+ }
}
- DBG("Unlinking all unix socket");
- unlink(client_unix_sock_path);
- unlink(apps_unix_sock_path);
- unlink(kconsumerd_err_unix_sock_path);
+ DBG("Cleaning up all session");
- DBG("Removing %s directory", LTTNG_RUNDIR);
- ret = asprintf(&cmd, "rm -rf " LTTNG_RUNDIR);
- if (ret < 0) {
- ERR("asprintf failed. Something is really wrong!");
- }
+ /* Destroy session list mutex */
+ if (session_list_ptr != NULL) {
+ pthread_mutex_destroy(&session_list_ptr->lock);
- /* Remove lttng run directory */
- ret = system(cmd);
- if (ret < 0) {
- ERR("Unable to clean " LTTNG_RUNDIR);
+ /* Cleanup ALL session */
+ cds_list_for_each_entry_safe(sess, stmp,
+ &session_list_ptr->head, list) {
+ teardown_kernel_session(sess);
+ // TODO complete session cleanup (including UST)
+ }
}
- DBG("Cleaning up all session");
- /* Cleanup ALL session */
- cds_list_for_each_entry(sess, <t_session_list.head, list) {
- teardown_kernel_session(sess);
- // TODO complete session cleanup (including UST)
- }
+ DBG("Closing all UST sockets");
+ clean_traceable_apps_list();
+
+ pthread_mutex_destroy(&kconsumerd_pid_mutex);
DBG("Closing kernel fd");
close(kernel_tracer_fd);
+
+ if (is_root) {
+ DBG("Unloading kernel modules");
+ modprobe_remove_kernel_modules();
+ }
+
+ close(thread_quit_pipe[0]);
+ close(thread_quit_pipe[1]);
}
/*
- * send_unix_sock
+ * Send data on a unix socket using the liblttsessiondcomm API.
*
- * Send data on a unix socket using the liblttsessiondcomm API.
- *
- * Return lttcomm error code.
+ * Return lttcomm error code.
*/
static int send_unix_sock(int sock, void *buf, size_t len)
{
}
/*
- * clean_command_ctx
- *
- * Free memory of a command context structure.
+ * Free memory of a command context structure.
*/
-static void clean_command_ctx(struct command_ctx *cmd_ctx)
+static void clean_command_ctx(struct command_ctx **cmd_ctx)
{
- DBG("Clean command context structure %p", cmd_ctx);
- if (cmd_ctx) {
- if (cmd_ctx->llm) {
- free(cmd_ctx->llm);
+ DBG("Clean command context structure");
+ if (*cmd_ctx) {
+ if ((*cmd_ctx)->llm) {
+ free((*cmd_ctx)->llm);
}
- if (cmd_ctx->lsm) {
- free(cmd_ctx->lsm);
+ if ((*cmd_ctx)->lsm) {
+ free((*cmd_ctx)->lsm);
}
- free(cmd_ctx);
- cmd_ctx = NULL;
+ free(*cmd_ctx);
+ *cmd_ctx = NULL;
}
}
/*
- * send_kconsumerd_fds
- *
- * Send all stream fds of the kernel session to the consumer.
+ * Send all stream fds of kernel channel to the consumer.
*/
-static int send_kconsumerd_fds(int sock, struct ltt_kernel_session *session)
+static int send_kconsumerd_channel_fds(int sock,
+ struct ltt_kernel_channel *channel)
{
int ret;
size_t nb_fd;
struct ltt_kernel_stream *stream;
- struct ltt_kernel_channel *chan;
struct lttcomm_kconsumerd_header lkh;
struct lttcomm_kconsumerd_msg lkm;
- nb_fd = session->stream_count_global;
+ DBG("Sending fds of channel %s to kernel consumer",
+ channel->channel->name);
+
+ nb_fd = channel->stream_count;
/* Setup header */
- lkh.payload_size = (nb_fd + 1) * sizeof(struct lttcomm_kconsumerd_msg);
+ lkh.payload_size = nb_fd * sizeof(struct lttcomm_kconsumerd_msg);
lkh.cmd_type = ADD_STREAM;
DBG("Sending kconsumerd header");
- ret = lttcomm_send_unix_sock(sock, &lkh, sizeof(struct lttcomm_kconsumerd_header));
+ ret = lttcomm_send_unix_sock(sock, &lkh,
+ sizeof(struct lttcomm_kconsumerd_header));
if (ret < 0) {
perror("send kconsumerd header");
goto error;
}
- DBG("Sending metadata stream fd");
-
- /* Send metadata stream fd first */
- lkm.fd = session->metadata_stream_fd;
- lkm.state = ACTIVE_FD;
- lkm.max_sb_size = session->metadata->conf->attr.subbuf_size;
- strncpy(lkm.path_name, session->metadata->pathname, PATH_MAX);
-
- ret = lttcomm_send_fds_unix_sock(sock, &lkm, &lkm.fd, 1, sizeof(lkm));
- if (ret < 0) {
- perror("send kconsumerd fd");
- goto error;
- }
-
- cds_list_for_each_entry(chan, &session->channel_list.head, list) {
- cds_list_for_each_entry(stream, &chan->stream_list.head, list) {
+ cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
+ if (stream->fd != 0) {
lkm.fd = stream->fd;
lkm.state = stream->state;
- lkm.max_sb_size = chan->channel->attr.subbuf_size;
+ lkm.max_sb_size = channel->channel->attr.subbuf_size;
+ lkm.output = channel->channel->attr.output;
strncpy(lkm.path_name, stream->pathname, PATH_MAX);
+ lkm.path_name[PATH_MAX - 1] = '\0';
DBG("Sending fd %d to kconsumerd", lkm.fd);
- ret = lttcomm_send_fds_unix_sock(sock, &lkm, &lkm.fd, 1, sizeof(lkm));
+ ret = lttcomm_send_fds_unix_sock(sock, &lkm,
+ &lkm.fd, 1, sizeof(lkm));
if (ret < 0) {
perror("send kconsumerd fd");
goto error;
}
}
- DBG("Kconsumerd fds sent");
+ DBG("Kconsumerd channel fds sent");
return 0;
}
/*
- * create_trace_dir
- *
- * Create the trace output directory.
+ * Send all stream fds of the kernel session to the consumer.
*/
-static int create_trace_dir(struct ltt_kernel_session *session)
+static int send_kconsumerd_fds(struct ltt_kernel_session *session)
{
int ret;
struct ltt_kernel_channel *chan;
+ struct lttcomm_kconsumerd_header lkh;
+ struct lttcomm_kconsumerd_msg lkm;
- /* Create all channel directories */
- cds_list_for_each_entry(chan, &session->channel_list.head, list) {
- DBG("Creating trace directory at %s", chan->pathname);
- ret = mkdir_recursive(chan->pathname, S_IRWXU | S_IRWXG );
- if (ret < 0) {
- if (ret != EEXIST) {
- ERR("Trace directory creation error");
- goto error;
- }
- }
- }
+ /* Setup header */
+ lkh.payload_size = sizeof(struct lttcomm_kconsumerd_msg);
+ lkh.cmd_type = ADD_STREAM;
- return 0;
+ DBG("Sending kconsumerd header for metadata");
-error:
- return ret;
-}
+ ret = lttcomm_send_unix_sock(session->consumer_fd, &lkh,
+ sizeof(struct lttcomm_kconsumerd_header));
+ if (ret < 0) {
+ perror("send kconsumerd header");
+ goto error;
+ }
-/*
- * ust_connect_app
- *
- * Return a socket connected to the libust communication socket
- * of the application identified by the pid.
- *
- * If the pid is not found in the traceable list,
- * return -1 to indicate error.
- */
-static int ust_connect_app(pid_t pid)
-{
- int sock;
- struct ltt_traceable_app *lta;
+ DBG("Sending metadata stream fd");
- DBG("Connect to application pid %d", pid);
+ /* Extra protection. It's NOT suppose to be set to 0 at this point */
+ if (session->consumer_fd == 0) {
+ session->consumer_fd = kconsumerd_cmd_sock;
+ }
- lta = find_app_by_pid(pid);
- if (lta == NULL) {
- /* App not found */
- DBG("Application pid %d not found", pid);
- return -1;
+ if (session->metadata_stream_fd != 0) {
+ /* Send metadata stream fd first */
+ lkm.fd = session->metadata_stream_fd;
+ lkm.state = ACTIVE_FD;
+ lkm.max_sb_size = session->metadata->conf->attr.subbuf_size;
+ lkm.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
+ strncpy(lkm.path_name, session->metadata->pathname, PATH_MAX);
+ lkm.path_name[PATH_MAX - 1] = '\0';
+
+ ret = lttcomm_send_fds_unix_sock(session->consumer_fd, &lkm,
+ &lkm.fd, 1, sizeof(lkm));
+ if (ret < 0) {
+ perror("send kconsumerd fd");
+ goto error;
+ }
}
- sock = ustctl_connect_pid(lta->pid);
- if (sock < 0) {
- ERR("Fail connecting to the PID %d", pid);
+ cds_list_for_each_entry(chan, &session->channel_list.head, list) {
+ ret = send_kconsumerd_channel_fds(session->consumer_fd, chan);
+ if (ret < 0) {
+ goto error;
+ }
}
- return sock;
+ DBG("Kconsumerd fds (metadata and channel streams) sent");
+
+ return 0;
+
+error:
+ return ret;
}
/*
- * notify_apps
- *
- * Notify apps by writing 42 to a named pipe using name.
- * Every applications waiting for a ltt-sessiond will be notified
- * and re-register automatically to the session daemon.
- *
- * Return open or write error value.
+ * Notify UST applications using the shm mmap futex.
*/
-static int notify_apps(const char *name)
+static int notify_ust_apps(int active)
{
- int fd;
- int ret = -1;
+ char *wait_shm_mmap;
- DBG("Notify the global application pipe");
+ DBG("Notifying applications of session daemon state: %d", active);
- /* Try opening the global pipe */
- fd = open(name, O_WRONLY);
- if (fd < 0) {
+ /* See shm.c for this call implying mmap, shm and futex calls */
+ wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
+ if (wait_shm_mmap == NULL) {
goto error;
}
- /* Notify by writing on the pipe */
- ret = write(fd, "42", 2);
- if (ret < 0) {
- perror("write");
- }
+ /* Wake waiting process */
+ futex_wait_update((int32_t *) wait_shm_mmap, active);
+
+ /* Apps notified successfully */
+ return 0;
error:
- return ret;
+ return -1;
}
/*
- * setup_lttng_msg
+ * Setup the outgoing data buffer for the response (llm) by allocating the
+ * right amount of memory and copying the original information from the lsm
+ * structure.
*
- * Setup the outgoing data buffer for the response (llm) by allocating the
- * right amount of memory and copying the original information from the lsm
- * structure.
- *
- * Return total size of the buffer pointed by buf.
+ * Return total size of the buffer pointed by buf.
*/
static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
{
/* Copy common data */
cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
- cmd_ctx->llm->pid = cmd_ctx->lsm->pid;
+ cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
cmd_ctx->llm->data_size = size;
cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
}
/*
- * thread_manage_kconsumerd
- *
- * This thread manage the kconsumerd error sent
- * back to the session daemon.
+ * Update the kernel poll set of all channel fd available over all tracing
+ * session. Add the wakeup pipe at the end of the set.
*/
-static void *thread_manage_kconsumerd(void *data)
+static int update_kernel_poll(struct lttng_poll_event *events)
{
- int sock, ret;
- enum lttcomm_return_code code;
-
- DBG("[thread] Manage kconsumerd started");
-
- ret = lttcomm_listen_unix_sock(kconsumerd_err_sock);
- if (ret < 0) {
- goto error;
- }
-
- sock = lttcomm_accept_unix_sock(kconsumerd_err_sock);
- if (sock < 0) {
- goto error;
- }
+ int ret;
+ struct ltt_session *session;
+ struct ltt_kernel_channel *channel;
- /* Getting status code from kconsumerd */
- ret = lttcomm_recv_unix_sock(sock, &code, sizeof(enum lttcomm_return_code));
- if (ret <= 0) {
- goto error;
- }
+ DBG("Updating kernel poll set");
- if (code == KCONSUMERD_COMMAND_SOCK_READY) {
- kconsumerd_cmd_sock = lttcomm_connect_unix_sock(kconsumerd_cmd_unix_sock_path);
- if (kconsumerd_cmd_sock < 0) {
- sem_post(&kconsumerd_sem);
- perror("kconsumerd connect");
- goto error;
+ session_lock_list();
+ cds_list_for_each_entry(session, &session_list_ptr->head, list) {
+ session_lock(session);
+ if (session->kernel_session == NULL) {
+ session_unlock(session);
+ continue;
}
- /* Signal condition to tell that the kconsumerd is ready */
- sem_post(&kconsumerd_sem);
- DBG("Kconsumerd command socket ready");
- } else {
- DBG("Kconsumerd error when waiting for SOCK_READY : %s",
- lttcomm_get_readable_code(-code));
- goto error;
- }
- /* Wait for any kconsumerd error */
- ret = lttcomm_recv_unix_sock(sock, &code, sizeof(enum lttcomm_return_code));
- if (ret <= 0) {
- ERR("Kconsumerd closed the command socket");
- goto error;
+ cds_list_for_each_entry(channel,
+ &session->kernel_session->channel_list.head, list) {
+ /* Add channel fd to the kernel poll set */
+ ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
+ if (ret < 0) {
+ session_unlock(session);
+ goto error;
+ }
+ DBG("Channel fd %d added to kernel set", channel->fd);
+ }
+ session_unlock(session);
}
+ session_unlock_list();
- ERR("Kconsumerd return code : %s", lttcomm_get_readable_code(-code));
+ return 0;
error:
- kconsumerd_pid = 0;
- DBG("Kconsumerd thread dying");
- return NULL;
+ session_unlock_list();
+ return -1;
}
/*
- * thread_manage_apps
+ * Find the channel fd from 'fd' over all tracing session. When found, check
+ * for new channel stream and send those stream fds to the kernel consumer.
*
- * This thread manage the application socket communication
+ * Useful for CPU hotplug feature.
*/
-static void *thread_manage_apps(void *data)
+static int update_kernel_stream(int fd)
{
- int sock, ret;
+ int ret = 0;
+ struct ltt_session *session;
+ struct ltt_kernel_channel *channel;
- /* TODO: Something more elegant is needed but fine for now */
- /* FIXME: change all types to either uint8_t, uint32_t, uint64_t
- * for 32-bit vs 64-bit compat processes. */
- /* replicate in ust with version number */
- struct {
- int reg; /* 1:register, 0:unregister */
- pid_t pid;
- uid_t uid;
- } reg_msg;
+ DBG("Updating kernel streams for channel fd %d", fd);
- DBG("[thread] Manage apps started");
+ session_lock_list();
+ cds_list_for_each_entry(session, &session_list_ptr->head, list) {
+ session_lock(session);
+ if (session->kernel_session == NULL) {
+ session_unlock(session);
+ continue;
+ }
- ret = lttcomm_listen_unix_sock(apps_sock);
- if (ret < 0) {
- goto error;
- }
-
- /* Notify all applications to register */
- notify_apps(default_global_apps_pipe);
-
- while (1) {
- DBG("Accepting application registration");
- /* Blocking call, waiting for transmission */
- sock = lttcomm_accept_unix_sock(apps_sock);
- if (sock < 0) {
- goto error;
+ /* This is not suppose to be 0 but this is an extra security check */
+ if (session->kernel_session->consumer_fd == 0) {
+ session->kernel_session->consumer_fd = kconsumerd_cmd_sock;
}
- /* Basic recv here to handle the very simple data
- * that the libust send to register (reg_msg).
- */
- ret = recv(sock, ®_msg, sizeof(reg_msg), 0);
- if (ret < 0) {
- perror("recv");
- continue;
- }
+ cds_list_for_each_entry(channel,
+ &session->kernel_session->channel_list.head, list) {
+ if (channel->fd == fd) {
+ DBG("Channel found, updating kernel streams");
+ ret = kernel_open_channel_stream(channel);
+ if (ret < 0) {
+ goto error;
+ }
- /* Add application to the global traceable list */
- if (reg_msg.reg == 1) {
- /* Registering */
- ret = register_traceable_app(reg_msg.pid, reg_msg.uid);
- if (ret < 0) {
- /* register_traceable_app only return an error with
- * ENOMEM. At this point, we better stop everything.
+ /*
+ * Have we already sent fds to the consumer? If yes, it means
+ * that tracing is started so it is safe to send our updated
+ * stream fds.
*/
+ if (session->kernel_session->kconsumer_fds_sent == 1) {
+ ret = send_kconsumerd_channel_fds(
+ session->kernel_session->consumer_fd, channel);
+ if (ret < 0) {
+ goto error;
+ }
+ }
goto error;
}
- } else {
- /* Unregistering */
- unregister_traceable_app(reg_msg.pid);
}
+ session_unlock(session);
}
+ session_unlock_list();
+ return ret;
error:
-
- return NULL;
+ session_unlock(session);
+ session_unlock_list();
+ return ret;
}
/*
- * spawn_kconsumerd_thread
+ * This thread manage event coming from the kernel.
*
- * Start the thread_manage_kconsumerd. This must be done after a kconsumerd
- * exec or it will fails.
+ * Features supported in this thread:
+ * -) CPU Hotplug
*/
-static int spawn_kconsumerd_thread(void)
+static void *thread_manage_kernel(void *data)
{
- int ret;
+ int ret, i, pollfd, update_poll_flag = 1;
+ uint32_t revents, nb_fd;
+ char tmp;
+ struct lttng_poll_event events;
- /* Setup semaphore */
- sem_init(&kconsumerd_sem, 0, 0);
+ DBG("Thread manage kernel started");
- ret = pthread_create(&kconsumerd_thread, NULL, thread_manage_kconsumerd, (void *) NULL);
- if (ret != 0) {
- perror("pthread_create kconsumerd");
+ ret = create_thread_poll_set(&events, 2);
+ if (ret < 0) {
goto error;
}
- /* Wait for the kconsumerd thread to be ready */
- sem_wait(&kconsumerd_sem);
-
- if (kconsumerd_pid == 0) {
- ERR("Kconsumerd did not start");
+ ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
+ if (ret < 0) {
goto error;
}
- return 0;
+ while (1) {
+ if (update_poll_flag == 1) {
+ ret = update_kernel_poll(&events);
+ if (ret < 0) {
+ goto error;
+ }
+ update_poll_flag = 0;
+ }
-error:
- ret = LTTCOMM_KERN_CONSUMER_FAIL;
- return ret;
-}
+ nb_fd = LTTNG_POLL_GETNB(&events);
-/*
- * spawn_kconsumerd
- *
- * Fork and exec a kernel consumer daemon (kconsumerd).
- *
- * NOTE: It is very important to fork a kconsumerd BEFORE opening any kernel
- * file descriptor using the libkernelctl or kernel-ctl functions. So, a
- * kernel consumer MUST only be spawned before creating a kernel session.
- *
- * Return pid if successful else -1.
- */
-static pid_t spawn_kconsumerd(void)
-{
- int ret;
- pid_t pid;
+ DBG("Thread kernel polling on %d fds", nb_fd);
- DBG("Spawning kconsumerd");
+ /* Zeroed the poll events */
+ lttng_poll_reset(&events);
- pid = fork();
- if (pid == 0) {
- /*
- * Exec kconsumerd.
- */
- execlp("kconsumerd", "kconsumerd", "--verbose", NULL);
- if (errno != 0) {
- perror("kernel start consumer exec");
+ /* Poll infinite value of time */
+ ret = lttng_poll_wait(&events, -1);
+ if (ret < 0) {
+ goto error;
+ } else if (ret == 0) {
+ /* Should not happen since timeout is infinite */
+ ERR("Return value of poll is 0 with an infinite timeout.\n"
+ "This should not have happened! Continuing...");
+ continue;
+ }
+
+ for (i = 0; i < nb_fd; i++) {
+ /* Fetch once the poll data */
+ revents = LTTNG_POLL_GETEV(&events, i);
+ pollfd = LTTNG_POLL_GETFD(&events, i);
+
+ /* Thread quit pipe has been closed. Killing thread. */
+ ret = check_thread_quit_pipe(pollfd, revents);
+ if (ret) {
+ goto error;
+ }
+
+ /* Check for data on kernel pipe */
+ if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
+ ret = read(kernel_poll_pipe[0], &tmp, 1);
+ update_poll_flag = 1;
+ continue;
+ } else {
+ /*
+ * New CPU detected by the kernel. Adding kernel stream to
+ * kernel session and updating the kernel consumer
+ */
+ if (revents & LPOLLIN) {
+ ret = update_kernel_stream(pollfd);
+ if (ret < 0) {
+ continue;
+ }
+ break;
+ /*
+ * TODO: We might want to handle the LPOLLERR | LPOLLHUP
+ * and unregister kernel stream at this point.
+ */
+ }
+ }
}
- exit(EXIT_FAILURE);
- } else if (pid > 0) {
- ret = pid;
- goto error;
- } else {
- perror("kernel start consumer fork");
- ret = -errno;
- goto error;
}
error:
- return ret;
+ DBG("Kernel thread dying");
+ close(kernel_poll_pipe[0]);
+ close(kernel_poll_pipe[1]);
+
+ lttng_poll_clean(&events);
+
+ return NULL;
}
/*
- * start_kconsumerd
- *
- * Spawn the kconsumerd daemon and session daemon thread.
+ * This thread manage the kconsumerd error sent back to the session daemon.
*/
-static int start_kconsumerd(void)
+static void *thread_manage_kconsumerd(void *data)
{
- int ret;
+ int sock = 0, i, ret, pollfd;
+ uint32_t revents, nb_fd;
+ enum lttcomm_return_code code;
+ struct lttng_poll_event events;
- pthread_mutex_lock(&kconsumerd_pid_mutex);
- if (kconsumerd_pid != 0) {
- goto end;
+ DBG("[thread] Manage kconsumerd started");
+
+ ret = lttcomm_listen_unix_sock(kconsumerd_err_sock);
+ if (ret < 0) {
+ goto error;
}
- ret = spawn_kconsumerd();
+ /*
+ * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
+ * Nothing more will be added to this poll set.
+ */
+ ret = create_thread_poll_set(&events, 2);
if (ret < 0) {
- ERR("Spawning kconsumerd failed");
- ret = LTTCOMM_KERN_CONSUMER_FAIL;
- pthread_mutex_unlock(&kconsumerd_pid_mutex);
goto error;
}
- /* Setting up the global kconsumerd_pid */
- kconsumerd_pid = ret;
- pthread_mutex_unlock(&kconsumerd_pid_mutex);
+ ret = lttng_poll_add(&events, kconsumerd_err_sock, LPOLLIN | LPOLLRDHUP);
+ if (ret < 0) {
+ goto error;
+ }
- DBG("Kconsumerd pid %d", ret);
+ nb_fd = LTTNG_POLL_GETNB(&events);
- DBG("Spawning kconsumerd thread");
- ret = spawn_kconsumerd_thread();
+ /* Inifinite blocking call, waiting for transmission */
+ ret = lttng_poll_wait(&events, -1);
if (ret < 0) {
- ERR("Fatal error spawning kconsumerd thread");
goto error;
}
-end:
- pthread_mutex_unlock(&kconsumerd_pid_mutex);
- return 0;
+ for (i = 0; i < nb_fd; i++) {
+ /* Fetch once the poll data */
+ revents = LTTNG_POLL_GETEV(&events, i);
+ pollfd = LTTNG_POLL_GETFD(&events, i);
-error:
- return ret;
-}
+ /* Thread quit pipe has been closed. Killing thread. */
+ ret = check_thread_quit_pipe(pollfd, revents);
+ if (ret) {
+ goto error;
+ }
-/*
- * init_kernel_tracer
- *
- * Setup necessary data for kernel tracer action.
- */
-static void init_kernel_tracer(void)
-{
- /* Set the global kernel tracer fd */
- kernel_tracer_fd = open(DEFAULT_KERNEL_TRACER_PATH, O_RDWR);
- if (kernel_tracer_fd < 0) {
- WARN("No kernel tracer available");
- kernel_tracer_fd = 0;
+ /* Event on the registration socket */
+ if (pollfd == kconsumerd_err_sock) {
+ if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
+ ERR("Kconsumerd err socket poll error");
+ goto error;
+ }
+ }
}
- DBG("Kernel tracer fd %d", kernel_tracer_fd);
-}
-
-/*
- * start_kernel_trace
- *
- * Start tracing by creating trace directory and sending FDs to the kernel
- * consumer.
- */
-static int start_kernel_trace(struct ltt_kernel_session *session)
-{
- int ret;
+ sock = lttcomm_accept_unix_sock(kconsumerd_err_sock);
+ if (sock < 0) {
+ goto error;
+ }
- /* Create trace directory */
- ret = create_trace_dir(session);
- if (ret < 0) {
- if (ret == -EEXIST) {
- ret = LTTCOMM_KERN_DIR_EXIST;
- } else {
- ret = LTTCOMM_KERN_DIR_FAIL;
- goto error;
- }
+ /* Getting status code from kconsumerd */
+ ret = lttcomm_recv_unix_sock(sock, &code,
+ sizeof(enum lttcomm_return_code));
+ if (ret <= 0) {
+ goto error;
}
- if (session->kconsumer_fds_sent == 0) {
- ret = send_kconsumerd_fds(kconsumerd_cmd_sock, session);
- if (ret < 0) {
- ERR("Send kconsumerd fds failed");
- ret = LTTCOMM_KERN_CONSUMER_FAIL;
+ if (code == KCONSUMERD_COMMAND_SOCK_READY) {
+ kconsumerd_cmd_sock =
+ lttcomm_connect_unix_sock(kconsumerd_cmd_unix_sock_path);
+ if (kconsumerd_cmd_sock < 0) {
+ sem_post(&kconsumerd_sem);
+ perror("kconsumerd connect");
goto error;
}
+ /* Signal condition to tell that the kconsumerd is ready */
+ sem_post(&kconsumerd_sem);
+ DBG("Kconsumerd command socket ready");
+ } else {
+ DBG("Kconsumerd error when waiting for SOCK_READY : %s",
+ lttcomm_get_readable_code(-code));
+ goto error;
+ }
- session->kconsumer_fds_sent = 1;
+ /* Remove the kconsumerd error sock since we've established a connexion */
+ ret = lttng_poll_del(&events, kconsumerd_err_sock);
+ if (ret < 0) {
+ goto error;
}
-error:
- return ret;
-}
+ ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
+ if (ret < 0) {
+ goto error;
+ }
-/*
- * init_default_channel
- *
- * Allocate a channel structure and fill it.
- */
-static struct lttng_channel *init_default_channel(void)
-{
- struct lttng_channel *chan;
+ /* Update number of fd */
+ nb_fd = LTTNG_POLL_GETNB(&events);
- chan = malloc(sizeof(struct lttng_channel));
- if (chan == NULL) {
- perror("init channel malloc");
+ /* Inifinite blocking call, waiting for transmission */
+ ret = lttng_poll_wait(&events, -1);
+ if (ret < 0) {
goto error;
}
- if (snprintf(chan->name, NAME_MAX, DEFAULT_CHANNEL_NAME) < 0) {
- perror("snprintf defautl channel name");
- return NULL;
+ for (i = 0; i < nb_fd; i++) {
+ /* Fetch once the poll data */
+ revents = LTTNG_POLL_GETEV(&events, i);
+ pollfd = LTTNG_POLL_GETFD(&events, i);
+
+ /* Thread quit pipe has been closed. Killing thread. */
+ ret = check_thread_quit_pipe(pollfd, revents);
+ if (ret) {
+ goto error;
+ }
+
+ /* Event on the kconsumerd socket */
+ if (pollfd == sock) {
+ if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
+ ERR("Kconsumerd err socket second poll error");
+ goto error;
+ }
+ }
+ }
+
+ /* Wait for any kconsumerd error */
+ ret = lttcomm_recv_unix_sock(sock, &code,
+ sizeof(enum lttcomm_return_code));
+ if (ret <= 0) {
+ ERR("Kconsumerd closed the command socket");
+ goto error;
}
- chan->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE;
- chan->attr.subbuf_size = DEFAULT_CHANNEL_SUBBUF_SIZE;
- chan->attr.num_subbuf = DEFAULT_CHANNEL_SUBBUF_NUM;
- chan->attr.switch_timer_interval = DEFAULT_CHANNEL_SWITCH_TIMER;
- chan->attr.read_timer_interval = DEFAULT_CHANNEL_READ_TIMER;
- chan->attr.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
+ ERR("Kconsumerd return code : %s", lttcomm_get_readable_code(-code));
error:
- return chan;
+ DBG("Kconsumerd thread dying");
+ close(kconsumerd_err_sock);
+ close(kconsumerd_cmd_sock);
+ close(sock);
+
+ unlink(kconsumerd_err_unix_sock_path);
+ unlink(kconsumerd_cmd_unix_sock_path);
+ kconsumerd_pid = 0;
+
+ lttng_poll_clean(&events);
+
+ return NULL;
}
/*
- * create_kernel_session
- *
- * Create a kernel tracer session then create the default channel.
+ * This thread manage application communication.
*/
-static int create_kernel_session(struct ltt_session *session)
+static void *thread_manage_apps(void *data)
{
- int ret;
- struct lttng_channel *chan;
+ int i, ret, pollfd;
+ uint32_t revents, nb_fd;
+ struct ust_command ust_cmd;
+ struct lttng_poll_event events;
- DBG("Creating kernel session");
+ DBG("[thread] Manage application started");
- ret = kernel_create_session(session, kernel_tracer_fd);
+ ret = create_thread_poll_set(&events, 2);
if (ret < 0) {
- ret = LTTCOMM_KERN_SESS_FAIL;
- goto error;
- }
-
- chan = init_default_channel();
- if (chan == NULL) {
- ret = LTTCOMM_FATAL;
goto error;
}
- DBG("Creating default kernel channel %s", DEFAULT_CHANNEL_NAME);
-
- ret = kernel_create_channel(session->kernel_session, chan, session->path);
+ ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
if (ret < 0) {
- ret = LTTCOMM_KERN_CHAN_FAIL;
goto error;
}
-error:
- return ret;
-}
+ while (1) {
+ /* Zeroed the events structure */
+ lttng_poll_reset(&events);
-/*
- * process_client_msg
- *
- * Process the command requested by the lttng client within the command
- * context structure. This function make sure that the return structure (llm)
- * is set and ready for transmission before returning.
- *
- * Return any error encountered or 0 for success.
- */
-static int process_client_msg(struct command_ctx *cmd_ctx)
-{
- int ret;
+ nb_fd = LTTNG_POLL_GETNB(&events);
- DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
+ DBG("Apps thread polling on %d fds", nb_fd);
- /* Listing commands don't need a session */
- switch (cmd_ctx->lsm->cmd_type) {
- case LTTNG_CREATE_SESSION:
- case LTTNG_LIST_SESSIONS:
- case LTTNG_LIST_EVENTS:
- case LTTNG_KERNEL_LIST_EVENTS:
- case LTTNG_LIST_TRACEABLE_APPS:
- break;
- default:
- DBG("Getting session %s by name", cmd_ctx->lsm->session_name);
- cmd_ctx->session = find_session_by_name(cmd_ctx->lsm->session_name);
- if (cmd_ctx->session == NULL) {
- /* If session name not found */
- if (cmd_ctx->lsm->session_name != NULL) {
- ret = LTTCOMM_SESS_NOT_FOUND;
- } else { /* If no session name specified */
- ret = LTTCOMM_SELECT_SESS;
- }
+ /* Inifinite blocking call, waiting for transmission */
+ ret = lttng_poll_wait(&events, -1);
+ if (ret < 0) {
goto error;
}
- break;
- }
- /*
- * Check kernel command for kernel session.
- */
- switch (cmd_ctx->lsm->cmd_type) {
- case LTTNG_KERNEL_ADD_CONTEXT:
- case LTTNG_KERNEL_CREATE_CHANNEL:
- case LTTNG_KERNEL_DISABLE_ALL_EVENT:
- case LTTNG_KERNEL_DISABLE_CHANNEL:
- case LTTNG_KERNEL_DISABLE_EVENT:
- case LTTNG_KERNEL_ENABLE_ALL_EVENT:
- case LTTNG_KERNEL_ENABLE_CHANNEL:
- case LTTNG_KERNEL_ENABLE_EVENT:
- case LTTNG_KERNEL_LIST_EVENTS:
- /* Kernel tracer check */
- if (kernel_tracer_fd == 0) {
- init_kernel_tracer();
- if (kernel_tracer_fd == 0) {
- ret = LTTCOMM_KERN_NA;
- goto error;
- }
- }
-
- /* Need a session for kernel command */
- if (cmd_ctx->lsm->cmd_type != LTTNG_KERNEL_LIST_EVENTS &&
- cmd_ctx->session->kernel_session == NULL) {
+ for (i = 0; i < nb_fd; i++) {
+ /* Fetch once the poll data */
+ revents = LTTNG_POLL_GETEV(&events, i);
+ pollfd = LTTNG_POLL_GETFD(&events, i);
- ret = create_kernel_session(cmd_ctx->session);
- if (ret < 0) {
- ret = LTTCOMM_KERN_SESS_FAIL;
+ /* Thread quit pipe has been closed. Killing thread. */
+ ret = check_thread_quit_pipe(pollfd, revents);
+ if (ret) {
goto error;
}
- /* Start the kernel consumer daemon */
- if (kconsumerd_pid == 0) {
- ret = start_kconsumerd();
- if (ret < 0) {
+ /* Inspect the apps cmd pipe */
+ if (pollfd == apps_cmd_pipe[0]) {
+ if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
+ ERR("Apps command pipe error");
goto error;
- }
- }
- }
- }
-
- /* Connect to ust apps if available pid */
- if (cmd_ctx->lsm->pid > 0) {
- /* Connect to app using ustctl API */
- cmd_ctx->ust_sock = ust_connect_app(cmd_ctx->lsm->pid);
- if (cmd_ctx->ust_sock < 0) {
- ret = LTTCOMM_NO_TRACEABLE;
- goto error;
- }
- }
-
- /* Process by command type */
- switch (cmd_ctx->lsm->cmd_type) {
- case LTTNG_KERNEL_ADD_CONTEXT:
- {
- int found = 0, no_event = 0;
- struct ltt_kernel_channel *chan;
- struct ltt_kernel_event *event;
-
- /* Setup lttng message with no payload */
- ret = setup_lttng_msg(cmd_ctx, 0);
- if (ret < 0) {
- goto setup_error;
- }
-
- /* Check if event name is given */
- if (strlen(cmd_ctx->lsm->u.context.event_name) == 0) {
- no_event = 1;
- }
+ } else if (revents & LPOLLIN) {
+ /* Empty pipe */
+ ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
+ if (ret < 0 || ret < sizeof(ust_cmd)) {
+ perror("read apps cmd pipe");
+ goto error;
+ }
- if (strlen(cmd_ctx->lsm->u.context.channel_name) == 0) {
- /* Go over all channels */
- DBG("Adding context to all channels");
- cds_list_for_each_entry(chan,
- &cmd_ctx->session->kernel_session->channel_list.head, list) {
- if (no_event) {
- ret = kernel_add_channel_context(chan,
- &cmd_ctx->lsm->u.context.ctx);
+ /* Register applicaton to the session daemon */
+ ret = register_traceable_app(&ust_cmd.reg_msg,
+ ust_cmd.sock);
if (ret < 0) {
- continue;
+ /* Only critical ENOMEM error can be returned here */
+ goto error;
}
- } else {
- event = get_kernel_event_by_name(cmd_ctx->lsm->u.context.event_name, chan);
- if (event != NULL) {
- ret = kernel_add_event_context(event,
- &cmd_ctx->lsm->u.context.ctx);
+
+ ret = ustctl_register_done(ust_cmd.sock);
+ if (ret < 0) {
+ /*
+ * If the registration is not possible, we simply
+ * unregister the apps and continue
+ */
+ unregister_traceable_app(ust_cmd.sock);
+ } else {
+ /*
+ * We just need here to monitor the close of the UST
+ * socket and poll set monitor those by default.
+ */
+ ret = lttng_poll_add(&events, ust_cmd.sock, 0);
if (ret < 0) {
- ret = LTTCOMM_KERN_CONTEXT_FAIL;
goto error;
}
- found = 1;
- break;
- }
- }
- }
- } else {
- chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.context.channel_name,
- cmd_ctx->session->kernel_session);
- if (chan == NULL) {
- ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
- goto error;
- }
- if (no_event) {
- ret = kernel_add_channel_context(chan,
- &cmd_ctx->lsm->u.context.ctx);
- if (ret < 0) {
- ret = LTTCOMM_KERN_CONTEXT_FAIL;
- goto error;
+ DBG("Apps with sock %d added to poll set",
+ ust_cmd.sock);
+ }
+ break;
}
} else {
- event = get_kernel_event_by_name(cmd_ctx->lsm->u.context.event_name, chan);
- if (event != NULL) {
- ret = kernel_add_event_context(event,
- &cmd_ctx->lsm->u.context.ctx);
+ /*
+ * At this point, we know that a registered application made
+ * the event at poll_wait.
+ */
+ if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
+ /* Removing from the poll set */
+ ret = lttng_poll_del(&events, pollfd);
if (ret < 0) {
- ret = LTTCOMM_KERN_CONTEXT_FAIL;
goto error;
}
+
+ /* Socket closed */
+ unregister_traceable_app(pollfd);
+ break;
}
}
}
-
- if (!found && !no_event) {
- ret = LTTCOMM_NO_EVENT;
- goto error;
- }
-
- ret = LTTCOMM_OK;
- break;
}
- case LTTNG_KERNEL_CREATE_CHANNEL:
- {
- /* Setup lttng message with no payload */
- ret = setup_lttng_msg(cmd_ctx, 0);
- if (ret < 0) {
- goto setup_error;
- }
- /* Kernel tracer */
- DBG("Creating kernel channel");
+error:
+ DBG("Application communication apps dying");
+ close(apps_cmd_pipe[0]);
+ close(apps_cmd_pipe[1]);
- ret = kernel_create_channel(cmd_ctx->session->kernel_session,
- &cmd_ctx->lsm->u.channel.chan, cmd_ctx->session->path);
- if (ret < 0) {
- ret = LTTCOMM_KERN_CHAN_FAIL;
- goto error;
- }
+ lttng_poll_clean(&events);
- ret = LTTCOMM_OK;
- break;
- }
- case LTTNG_KERNEL_DISABLE_CHANNEL:
- {
- struct ltt_kernel_channel *chan;
+ return NULL;
+}
- /* Setup lttng message with no payload */
- ret = setup_lttng_msg(cmd_ctx, 0);
- if (ret < 0) {
- goto setup_error;
- }
+/*
+ * Dispatch request from the registration threads to the application
+ * communication thread.
+ */
+static void *thread_dispatch_ust_registration(void *data)
+{
+ int ret;
+ struct cds_wfq_node *node;
+ struct ust_command *ust_cmd = NULL;
+
+ DBG("[thread] Dispatch UST command started");
+
+ while (!dispatch_thread_exit) {
+ /* Atomically prepare the queue futex */
+ futex_nto1_prepare(&ust_cmd_queue.futex);
+
+ do {
+ /* Dequeue command for registration */
+ node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
+ if (node == NULL) {
+ DBG("Waked up but nothing in the UST command queue");
+ /* Continue thread execution */
+ break;
+ }
- chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.disable.channel_name,
- cmd_ctx->session->kernel_session);
- if (chan == NULL) {
- ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
- goto error;
- } else if (chan->enabled == 1) {
- ret = kernel_disable_channel(chan);
+ ust_cmd = caa_container_of(node, struct ust_command, node);
+
+ DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
+ " gid:%d sock:%d name:%s (version %d.%d)",
+ ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
+ ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
+ ust_cmd->sock, ust_cmd->reg_msg.name,
+ ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
+ /*
+ * Inform apps thread of the new application registration. This
+ * call is blocking so we can be assured that the data will be read
+ * at some point in time or wait to the end of the world :)
+ */
+ ret = write(apps_cmd_pipe[1], ust_cmd,
+ sizeof(struct ust_command));
if (ret < 0) {
- if (ret != EEXIST) {
- ret = LTTCOMM_KERN_CHAN_DISABLE_FAIL;
+ perror("write apps cmd pipe");
+ if (errno == EBADF) {
+ /*
+ * We can't inform the application thread to process
+ * registration. We will exit or else application
+ * registration will not occur and tracing will never
+ * start.
+ */
+ goto error;
}
- goto error;
}
- }
+ free(ust_cmd);
+ } while (node != NULL);
- kernel_wait_quiescent(kernel_tracer_fd);
- ret = LTTCOMM_OK;
- break;
+ /* Futex wait on queue. Blocking call on futex() */
+ futex_nto1_wait(&ust_cmd_queue.futex);
}
- case LTTNG_KERNEL_DISABLE_EVENT:
- {
- struct ltt_kernel_channel *chan;
- struct ltt_kernel_event *ev;
- /* Setup lttng message with no payload */
- ret = setup_lttng_msg(cmd_ctx, 0);
- if (ret < 0) {
- goto setup_error;
- }
+error:
+ DBG("Dispatch thread dying");
+ return NULL;
+}
- chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.disable.channel_name,
- cmd_ctx->session->kernel_session);
- if (chan == NULL) {
- ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
- goto error;
- }
+/*
+ * This thread manage application registration.
+ */
+static void *thread_registration_apps(void *data)
+{
+ int sock = 0, i, ret, pollfd;
+ uint32_t revents, nb_fd;
+ struct lttng_poll_event events;
+ /*
+ * Get allocated in this thread, enqueued to a global queue, dequeued and
+ * freed in the manage apps thread.
+ */
+ struct ust_command *ust_cmd = NULL;
- ev = get_kernel_event_by_name(cmd_ctx->lsm->u.disable.name, chan);
- if (ev != NULL) {
- DBG("Disabling kernel event %s for channel %s.",
- cmd_ctx->lsm->u.disable.name, cmd_ctx->lsm->u.disable.channel_name);
- ret = kernel_disable_event(ev);
- if (ret < 0) {
- ret = LTTCOMM_KERN_ENABLE_FAIL;
- goto error;
- }
- }
+ DBG("[thread] Manage application registration started");
- kernel_wait_quiescent(kernel_tracer_fd);
- ret = LTTCOMM_OK;
- break;
+ ret = lttcomm_listen_unix_sock(apps_sock);
+ if (ret < 0) {
+ goto error;
}
- case LTTNG_KERNEL_DISABLE_ALL_EVENT:
- {
- struct ltt_kernel_channel *chan;
- struct ltt_kernel_event *ev;
- /* Setup lttng message with no payload */
- ret = setup_lttng_msg(cmd_ctx, 0);
- if (ret < 0) {
- goto setup_error;
- }
+ /*
+ * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
+ * more will be added to this poll set.
+ */
+ ret = create_thread_poll_set(&events, 2);
+ if (ret < 0) {
+ goto error;
+ }
- DBG("Disabling all enabled kernel events");
+ /* Add the application registration socket */
+ ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
+ if (ret < 0) {
+ goto error;
+ }
- chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.disable.channel_name,
- cmd_ctx->session->kernel_session);
- if (chan == NULL) {
- ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
- goto error;
- }
+ /* Notify all applications to register */
+ ret = notify_ust_apps(1);
+ if (ret < 0) {
+ ERR("Failed to notify applications or create the wait shared memory.\n"
+ "Execution continues but there might be problem for already\n"
+ "running applications that wishes to register.");
+ }
- /* For each event in the kernel session */
- cds_list_for_each_entry(ev, &chan->events_list.head, list) {
- DBG("Disabling kernel event %s for channel %s.",
- ev->event->name, cmd_ctx->lsm->u.disable.channel_name);
- ret = kernel_disable_event(ev);
- if (ret < 0) {
- continue;
- }
- }
+ while (1) {
+ DBG("Accepting application registration");
- /* Quiescent wait after event disable */
- kernel_wait_quiescent(kernel_tracer_fd);
- ret = LTTCOMM_OK;
- break;
- }
- case LTTNG_KERNEL_ENABLE_CHANNEL:
- {
- struct ltt_kernel_channel *chan;
+ nb_fd = LTTNG_POLL_GETNB(&events);
- /* Setup lttng message with no payload */
- ret = setup_lttng_msg(cmd_ctx, 0);
+ /* Inifinite blocking call, waiting for transmission */
+ ret = lttng_poll_wait(&events, -1);
if (ret < 0) {
- goto setup_error;
+ goto error;
}
- chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.enable.channel_name,
- cmd_ctx->session->kernel_session);
- if (chan == NULL) {
- ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
- goto error;
- } else if (chan->enabled == 0) {
- ret = kernel_enable_channel(chan);
- if (ret < 0) {
- if (ret != EEXIST) {
- ret = LTTCOMM_KERN_CHAN_ENABLE_FAIL;
- }
+ for (i = 0; i < nb_fd; i++) {
+ /* Fetch once the poll data */
+ revents = LTTNG_POLL_GETEV(&events, i);
+ pollfd = LTTNG_POLL_GETFD(&events, i);
+
+ /* Thread quit pipe has been closed. Killing thread. */
+ ret = check_thread_quit_pipe(pollfd, revents);
+ if (ret) {
goto error;
}
- }
-
- kernel_wait_quiescent(kernel_tracer_fd);
- ret = LTTCOMM_OK;
- break;
- }
- case LTTNG_KERNEL_ENABLE_EVENT:
- {
- struct ltt_kernel_channel *chan;
- struct ltt_kernel_event *ev;
- /* Setup lttng message with no payload */
- ret = setup_lttng_msg(cmd_ctx, 0);
- if (ret < 0) {
- goto setup_error;
- }
+ /* Event on the registration socket */
+ if (pollfd == apps_sock) {
+ if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
+ ERR("Register apps socket poll error");
+ goto error;
+ } else if (revents & LPOLLIN) {
+ sock = lttcomm_accept_unix_sock(apps_sock);
+ if (sock < 0) {
+ goto error;
+ }
- chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.enable.channel_name,
- cmd_ctx->session->kernel_session);
- if (chan == NULL) {
- ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
- goto error;
- }
+ /* Create UST registration command for enqueuing */
+ ust_cmd = malloc(sizeof(struct ust_command));
+ if (ust_cmd == NULL) {
+ perror("ust command malloc");
+ goto error;
+ }
- ev = get_kernel_event_by_name(cmd_ctx->lsm->u.enable.event.name, chan);
- if (ev == NULL) {
- DBG("Creating kernel event %s for channel %s.",
- cmd_ctx->lsm->u.enable.event.name, chan->channel->name);
- ret = kernel_create_event(&cmd_ctx->lsm->u.enable.event, chan);
- } else {
- DBG("Enabling kernel event %s for channel %s.",
- cmd_ctx->lsm->u.enable.event.name, chan->channel->name);
- ret = kernel_enable_event(ev);
- }
+ /*
+ * Using message-based transmissions to ensure we don't
+ * have to deal with partially received messages.
+ */
+ ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
+ sizeof(struct ust_register_msg));
+ if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
+ if (ret < 0) {
+ perror("lttcomm_recv_unix_sock register apps");
+ } else {
+ ERR("Wrong size received on apps register");
+ }
+ free(ust_cmd);
+ close(sock);
+ continue;
+ }
- if (ret < 0) {
- ret = LTTCOMM_KERN_ENABLE_FAIL;
- goto error;
+ ust_cmd->sock = sock;
+
+ DBG("UST registration received with pid:%d ppid:%d uid:%d"
+ " gid:%d sock:%d name:%s (version %d.%d)",
+ ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
+ ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
+ ust_cmd->sock, ust_cmd->reg_msg.name,
+ ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
+
+ /*
+ * Lock free enqueue the registration request. The red pill
+ * has been taken! This apps will be part of the *system*.
+ */
+ cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
+
+ /*
+ * Wake the registration queue futex. Implicit memory
+ * barrier with the exchange in cds_wfq_enqueue.
+ */
+ futex_nto1_wake(&ust_cmd_queue.futex);
+ }
+ }
}
-
- kernel_wait_quiescent(kernel_tracer_fd);
- ret = LTTCOMM_OK;
- break;
}
- case LTTNG_KERNEL_ENABLE_ALL_EVENT:
- {
- int pos, size;
- char *event_list, *event, *ptr;
- struct ltt_kernel_channel *chan;
- struct ltt_kernel_event *ev;
- struct lttng_event ev_attr;
-
- /* Setup lttng message with no payload */
- ret = setup_lttng_msg(cmd_ctx, 0);
- if (ret < 0) {
- goto setup_error;
- }
- DBG("Enabling all kernel event");
+error:
+ DBG("UST Registration thread dying");
- chan = get_kernel_channel_by_name(cmd_ctx->lsm->u.enable.channel_name,
- cmd_ctx->session->kernel_session);
- if (chan == NULL) {
- ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
- goto error;
- }
+ /* Notify that the registration thread is gone */
+ notify_ust_apps(0);
- /* For each event in the kernel session */
- cds_list_for_each_entry(ev, &chan->events_list.head, list) {
- DBG("Enabling kernel event %s for channel %s.",
- ev->event->name, chan->channel->name);
- ret = kernel_enable_event(ev);
- if (ret < 0) {
- continue;
- }
- }
+ close(apps_sock);
+ close(sock);
+ unlink(apps_unix_sock_path);
- size = kernel_list_events(kernel_tracer_fd, &event_list);
- if (size < 0) {
- ret = LTTCOMM_KERN_LIST_FAIL;
- goto error;
- }
+ lttng_poll_clean(&events);
- ptr = event_list;
- while ((size = sscanf(ptr, "event { name = %m[^;]; };%n\n", &event, &pos)) == 1) {
- ev = get_kernel_event_by_name(event, chan);
- if (ev == NULL) {
- strncpy(ev_attr.name, event, LTTNG_SYM_NAME_LEN);
- /* Default event type for enable all */
- ev_attr.type = LTTNG_EVENT_TRACEPOINTS;
- /* Enable each single tracepoint event */
- ret = kernel_create_event(&ev_attr, chan);
- if (ret < 0) {
- /* Ignore error here and continue */
- }
- }
+ return NULL;
+}
- /* Move pointer to the next line */
- ptr += pos + 1;
- free(event);
- }
+/*
+ * Start the thread_manage_kconsumerd. This must be done after a kconsumerd
+ * exec or it will fails.
+ */
+static int spawn_kconsumerd_thread(void)
+{
+ int ret;
- free(event_list);
+ /* Setup semaphore */
+ sem_init(&kconsumerd_sem, 0, 0);
- /* Quiescent wait after event enable */
- kernel_wait_quiescent(kernel_tracer_fd);
- ret = LTTCOMM_OK;
- break;
+ ret = pthread_create(&kconsumerd_thread, NULL,
+ thread_manage_kconsumerd, (void *) NULL);
+ if (ret != 0) {
+ perror("pthread_create kconsumerd");
+ goto error;
}
- case LTTNG_KERNEL_LIST_EVENTS:
- {
- char *event_list;
- ssize_t size = 0;
- DBG("Listing kernel events");
+ /* Wait for the kconsumerd thread to be ready */
+ sem_wait(&kconsumerd_sem);
- size = kernel_list_events(kernel_tracer_fd, &event_list);
- if (size < 0) {
- ret = LTTCOMM_KERN_LIST_FAIL;
- goto error;
- }
+ if (kconsumerd_pid == 0) {
+ ERR("Kconsumerd did not start");
+ goto error;
+ }
- /*
- * Setup lttng message with payload size set to the event list size in
- * bytes and then copy list into the llm payload.
- */
- ret = setup_lttng_msg(cmd_ctx, size);
- if (ret < 0) {
- goto setup_error;
- }
+ return 0;
- /* Copy event list into message payload */
- memcpy(cmd_ctx->llm->payload, event_list, size);
+error:
+ ret = LTTCOMM_KERN_CONSUMER_FAIL;
+ return ret;
+}
- free(event_list);
+/*
+ * Join kernel consumer thread
+ */
+static int join_kconsumerd_thread(void)
+{
+ void *status;
+ int ret;
- ret = LTTCOMM_OK;
- break;
+ if (kconsumerd_pid != 0) {
+ ret = kill(kconsumerd_pid, SIGTERM);
+ if (ret) {
+ ERR("Error killing kconsumerd");
+ return ret;
+ }
+ return pthread_join(kconsumerd_thread, &status);
+ } else {
+ return 0;
}
- case LTTNG_START_TRACE:
- {
- struct ltt_kernel_channel *chan;
+}
- /* Setup lttng message with no payload */
- ret = setup_lttng_msg(cmd_ctx, 0);
+/*
+ * Fork and exec a kernel consumer daemon (kconsumerd).
+ *
+ * Return pid if successful else -1.
+ */
+static pid_t spawn_kconsumerd(void)
+{
+ int ret;
+ pid_t pid;
+ const char *verbosity;
+
+ DBG("Spawning kconsumerd");
+
+ pid = fork();
+ if (pid == 0) {
+ /*
+ * Exec kconsumerd.
+ */
+ if (opt_verbose > 1 || opt_verbose_kconsumerd) {
+ verbosity = "--verbose";
+ } else {
+ verbosity = "--quiet";
+ }
+ execl(INSTALL_BIN_PATH "/ltt-kconsumerd",
+ "ltt-kconsumerd", verbosity, NULL);
+ if (errno != 0) {
+ perror("kernel start consumer exec");
+ }
+ exit(EXIT_FAILURE);
+ } else if (pid > 0) {
+ ret = pid;
+ goto error;
+ } else {
+ perror("kernel start consumer fork");
+ ret = -errno;
+ goto error;
+ }
+
+error:
+ return ret;
+}
+
+/*
+ * Spawn the kconsumerd daemon and session daemon thread.
+ */
+static int start_kconsumerd(void)
+{
+ int ret;
+
+ pthread_mutex_lock(&kconsumerd_pid_mutex);
+ if (kconsumerd_pid != 0) {
+ pthread_mutex_unlock(&kconsumerd_pid_mutex);
+ goto end;
+ }
+
+ ret = spawn_kconsumerd();
+ if (ret < 0) {
+ ERR("Spawning kconsumerd failed");
+ ret = LTTCOMM_KERN_CONSUMER_FAIL;
+ pthread_mutex_unlock(&kconsumerd_pid_mutex);
+ goto error;
+ }
+
+ /* Setting up the global kconsumerd_pid */
+ kconsumerd_pid = ret;
+ pthread_mutex_unlock(&kconsumerd_pid_mutex);
+
+ DBG("Kconsumerd pid %d", ret);
+
+ DBG("Spawning kconsumerd thread");
+ ret = spawn_kconsumerd_thread();
+ if (ret < 0) {
+ ERR("Fatal error spawning kconsumerd thread");
+ goto error;
+ }
+
+end:
+ return 0;
+
+error:
+ return ret;
+}
+
+/*
+ * modprobe_kernel_modules
+ */
+static int modprobe_kernel_modules(void)
+{
+ int ret = 0, i;
+ char modprobe[256];
+
+ for (i = 0; i < ARRAY_SIZE(kernel_modules_list); i++) {
+ ret = snprintf(modprobe, sizeof(modprobe),
+ "/sbin/modprobe %s%s",
+ kernel_modules_list[i].required ? "" : "--quiet ",
+ kernel_modules_list[i].name);
if (ret < 0) {
- goto setup_error;
+ perror("snprintf modprobe");
+ goto error;
+ }
+ modprobe[sizeof(modprobe) - 1] = '\0';
+ ret = system(modprobe);
+ if (ret == -1) {
+ ERR("Unable to launch modprobe for module %s",
+ kernel_modules_list[i].name);
+ } else if (kernel_modules_list[i].required
+ && WEXITSTATUS(ret) != 0) {
+ ERR("Unable to load module %s",
+ kernel_modules_list[i].name);
+ } else {
+ DBG("Modprobe successfully %s",
+ kernel_modules_list[i].name);
+ }
+ }
+
+error:
+ return ret;
+}
+
+/*
+ * mount_debugfs
+ */
+static int mount_debugfs(char *path)
+{
+ int ret;
+ char *type = "debugfs";
+
+ ret = mkdir_recursive(path, S_IRWXU | S_IRWXG, geteuid(), getegid());
+ if (ret < 0) {
+ goto error;
+ }
+
+ ret = mount(type, path, type, 0, NULL);
+ if (ret < 0) {
+ perror("mount debugfs");
+ goto error;
+ }
+
+ DBG("Mounted debugfs successfully at %s", path);
+
+error:
+ return ret;
+}
+
+/*
+ * Setup necessary data for kernel tracer action.
+ */
+static void init_kernel_tracer(void)
+{
+ int ret;
+ char *proc_mounts = "/proc/mounts";
+ char line[256];
+ char *debugfs_path = NULL, *lttng_path = NULL;
+ FILE *fp;
+
+ /* Detect debugfs */
+ fp = fopen(proc_mounts, "r");
+ if (fp == NULL) {
+ ERR("Unable to probe %s", proc_mounts);
+ goto error;
+ }
+
+ while (fgets(line, sizeof(line), fp) != NULL) {
+ if (strstr(line, "debugfs") != NULL) {
+ /* Remove first string */
+ strtok(line, " ");
+ /* Dup string here so we can reuse line later on */
+ debugfs_path = strdup(strtok(NULL, " "));
+ DBG("Got debugfs path : %s", debugfs_path);
+ break;
+ }
+ }
+
+ fclose(fp);
+
+ /* Mount debugfs if needded */
+ if (debugfs_path == NULL) {
+ ret = asprintf(&debugfs_path, "/mnt/debugfs");
+ if (ret < 0) {
+ perror("asprintf debugfs path");
+ goto error;
+ }
+ ret = mount_debugfs(debugfs_path);
+ if (ret < 0) {
+ goto error;
+ }
+ }
+
+ /* Modprobe lttng kernel modules */
+ ret = modprobe_kernel_modules();
+ if (ret < 0) {
+ goto error;
+ }
+
+ /* Setup lttng kernel path */
+ ret = asprintf(<tng_path, "%s/lttng", debugfs_path);
+ if (ret < 0) {
+ perror("asprintf lttng path");
+ goto error;
+ }
+
+ /* Open debugfs lttng */
+ kernel_tracer_fd = open(lttng_path, O_RDWR);
+ if (kernel_tracer_fd < 0) {
+ DBG("Failed to open %s", lttng_path);
+ goto error;
+ }
+
+ free(lttng_path);
+ free(debugfs_path);
+ DBG("Kernel tracer fd %d", kernel_tracer_fd);
+ return;
+
+error:
+ if (lttng_path) {
+ free(lttng_path);
+ }
+ if (debugfs_path) {
+ free(debugfs_path);
+ }
+ WARN("No kernel tracer available");
+ kernel_tracer_fd = 0;
+ return;
+}
+
+/*
+ * Init tracing by creating trace directory and sending fds kernel consumer.
+ */
+static int init_kernel_tracing(struct ltt_kernel_session *session)
+{
+ int ret = 0;
+
+ if (session->kconsumer_fds_sent == 0) {
+ /*
+ * Assign default kernel consumer socket if no consumer assigned to the
+ * kernel session. At this point, it's NOT suppose to be 0 but this is
+ * an extra security check.
+ */
+ if (session->consumer_fd == 0) {
+ session->consumer_fd = kconsumerd_cmd_sock;
+ }
+
+ ret = send_kconsumerd_fds(session);
+ if (ret < 0) {
+ ret = LTTCOMM_KERN_CONSUMER_FAIL;
+ goto error;
+ }
+
+ session->kconsumer_fds_sent = 1;
+ }
+
+error:
+ return ret;
+}
+
+/*
+ * Create an UST session and add it to the session ust list.
+ */
+static int create_ust_session(pid_t pid, struct ltt_session *session)
+{
+ int ret = -1;
+ struct ltt_ust_session *lus;
+
+ DBG("Creating UST session");
+
+ lus = trace_ust_create_session(session->path, pid);
+ if (lus == NULL) {
+ goto error;
+ }
+
+ ret = mkdir_recursive(lus->path, S_IRWXU | S_IRWXG,
+ geteuid(), allowed_group());
+ if (ret < 0) {
+ if (ret != -EEXIST) {
+ ERR("Trace directory creation error");
+ goto error;
+ }
+ }
+
+ /* Create session on the UST tracer */
+ ret = ustctl_create_session(lus);
+ if (ret < 0) {
+ goto error;
+ }
+
+ return 0;
+
+error:
+ free(lus);
+ return ret;
+}
+
+/*
+ * Create a kernel tracer session then create the default channel.
+ */
+static int create_kernel_session(struct ltt_session *session)
+{
+ int ret;
+
+ DBG("Creating kernel session");
+
+ ret = kernel_create_session(session, kernel_tracer_fd);
+ if (ret < 0) {
+ ret = LTTCOMM_KERN_SESS_FAIL;
+ goto error;
+ }
+
+ /* Set kernel consumer socket fd */
+ if (kconsumerd_cmd_sock) {
+ session->kernel_session->consumer_fd = kconsumerd_cmd_sock;
+ }
+
+ ret = mkdir_recursive(session->kernel_session->trace_path,
+ S_IRWXU | S_IRWXG, geteuid(), allowed_group());
+ if (ret < 0) {
+ if (ret != -EEXIST) {
+ ERR("Trace directory creation error");
+ goto error;
+ }
+ }
+
+error:
+ return ret;
+}
+
+/*
+ * Using the session list, filled a lttng_session array to send back to the
+ * client for session listing.
+ *
+ * The session list lock MUST be acquired before calling this function. Use
+ * session_lock_list() and session_unlock_list().
+ */
+static void list_lttng_sessions(struct lttng_session *sessions)
+{
+ int i = 0;
+ struct ltt_session *session;
+
+ DBG("Getting all available session");
+ /*
+ * Iterate over session list and append data after the control struct in
+ * the buffer.
+ */
+ cds_list_for_each_entry(session, &session_list_ptr->head, list) {
+ strncpy(sessions[i].path, session->path, PATH_MAX);
+ sessions[i].path[PATH_MAX - 1] = '\0';
+ strncpy(sessions[i].name, session->name, NAME_MAX);
+ sessions[i].name[NAME_MAX - 1] = '\0';
+ i++;
+ }
+}
+
+/*
+ * Fill lttng_channel array of all channels.
+ */
+static void list_lttng_channels(struct ltt_session *session,
+ struct lttng_channel *channels)
+{
+ int i = 0;
+ struct ltt_kernel_channel *kchan;
+
+ DBG("Listing channels for session %s", session->name);
+
+ /* Kernel channels */
+ if (session->kernel_session != NULL) {
+ cds_list_for_each_entry(kchan,
+ &session->kernel_session->channel_list.head, list) {
+ /* Copy lttng_channel struct to array */
+ memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
+ channels[i].enabled = kchan->enabled;
+ i++;
+ }
+ }
+
+ /* TODO: Missing UST listing */
+}
+
+/*
+ * Fill lttng_event array of all events in the channel.
+ */
+static void list_lttng_events(struct ltt_kernel_channel *kchan,
+ struct lttng_event *events)
+{
+ /*
+ * TODO: This is ONLY kernel. Need UST support.
+ */
+ int i = 0;
+ struct ltt_kernel_event *event;
+
+ DBG("Listing events for channel %s", kchan->channel->name);
+
+ /* Kernel channels */
+ cds_list_for_each_entry(event, &kchan->events_list.head , list) {
+ strncpy(events[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
+ events[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
+ events[i].enabled = event->enabled;
+ switch (event->event->instrumentation) {
+ case LTTNG_KERNEL_TRACEPOINT:
+ events[i].type = LTTNG_EVENT_TRACEPOINT;
+ break;
+ case LTTNG_KERNEL_KPROBE:
+ case LTTNG_KERNEL_KRETPROBE:
+ events[i].type = LTTNG_EVENT_PROBE;
+ memcpy(&events[i].attr.probe, &event->event->u.kprobe,
+ sizeof(struct lttng_kernel_kprobe));
+ break;
+ case LTTNG_KERNEL_FUNCTION:
+ events[i].type = LTTNG_EVENT_FUNCTION;
+ memcpy(&events[i].attr.ftrace, &event->event->u.ftrace,
+ sizeof(struct lttng_kernel_function));
+ break;
+ case LTTNG_KERNEL_NOOP:
+ events[i].type = LTTNG_EVENT_NOOP;
+ break;
+ case LTTNG_KERNEL_SYSCALL:
+ events[i].type = LTTNG_EVENT_SYSCALL;
+ break;
+ }
+ i++;
+ }
+}
+
+/*
+ * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
+ */
+static int cmd_disable_channel(struct ltt_session *session,
+ int domain, char *channel_name)
+{
+ int ret;
+
+ switch (domain) {
+ case LTTNG_DOMAIN_KERNEL:
+ ret = channel_kernel_disable(session->kernel_session,
+ channel_name);
+ if (ret != LTTCOMM_OK) {
+ goto error;
+ }
+
+ kernel_wait_quiescent(kernel_tracer_fd);
+ break;
+ default:
+ /* TODO: Userspace tracing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ goto error;
+ }
+
+ ret = LTTCOMM_OK;
+
+error:
+ return ret;
+}
+
+/*
+ * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
+ */
+static int cmd_enable_channel(struct ltt_session *session, int domain,
+ char *channel_name, struct lttng_channel *attr)
+{
+ int ret;
+ struct ltt_kernel_channel *kchan;
+
+ switch (domain) {
+ case LTTNG_DOMAIN_KERNEL:
+ kchan = trace_kernel_get_channel_by_name(channel_name,
+ session->kernel_session);
+ if (kchan == NULL) {
+ ret = channel_kernel_create(session->kernel_session,
+ channel_name, attr, kernel_poll_pipe[1]);
+ } else {
+ ret = channel_kernel_enable(session->kernel_session, kchan);
+ }
+
+ if (ret != LTTCOMM_OK) {
+ goto error;
+ }
+
+ kernel_wait_quiescent(kernel_tracer_fd);
+ break;
+ default:
+ /* TODO: Userspace tracing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ goto error;
+ }
+
+ ret = LTTCOMM_OK;
+
+error:
+ return ret;
+}
+
+/*
+ * Command LTTNG_DISABLE_EVENT processed by the client thread.
+ */
+static int cmd_disable_event(struct ltt_session *session, int domain,
+ char *channel_name, char *event_name)
+{
+ int ret;
+ struct ltt_kernel_channel *kchan;
+
+ switch (domain) {
+ case LTTNG_DOMAIN_KERNEL:
+ kchan = trace_kernel_get_channel_by_name(channel_name,
+ session->kernel_session);
+ if (kchan == NULL) {
+ ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
+ goto error;
+ }
+
+ ret = event_kernel_disable(session->kernel_session, kchan, event_name);
+ if (ret != LTTCOMM_OK) {
+ goto error;
+ }
+
+ kernel_wait_quiescent(kernel_tracer_fd);
+ break;
+ default:
+ /* TODO: Userspace tracing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ goto error;
+ }
+
+ ret = LTTCOMM_OK;
+
+error:
+ return ret;
+}
+
+/*
+ * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
+ */
+static int cmd_disable_event_all(struct ltt_session *session, int domain,
+ char *channel_name)
+{
+ int ret;
+ struct ltt_kernel_channel *kchan;
+
+ switch (domain) {
+ case LTTNG_DOMAIN_KERNEL:
+ kchan = trace_kernel_get_channel_by_name(channel_name,
+ session->kernel_session);
+ if (kchan == NULL) {
+ ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
+ goto error;
+ }
+
+ ret = event_kernel_disable_all(session->kernel_session, kchan);
+ if (ret != LTTCOMM_OK) {
+ goto error;
+ }
+
+ kernel_wait_quiescent(kernel_tracer_fd);
+ break;
+ default:
+ /* TODO: Userspace tracing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ goto error;
+ }
+
+ ret = LTTCOMM_OK;
+
+error:
+ return ret;
+}
+
+/*
+ * Command LTTNG_ADD_CONTEXT processed by the client thread.
+ */
+static int cmd_add_context(struct ltt_session *session, int domain,
+ char *channel_name, char *event_name, struct lttng_event_context *ctx)
+{
+ int ret;
+
+ switch (domain) {
+ case LTTNG_DOMAIN_KERNEL:
+ /* Add kernel context to kernel tracer */
+ ret = context_kernel_add(session->kernel_session, ctx,
+ event_name, channel_name);
+ if (ret != LTTCOMM_OK) {
+ goto error;
+ }
+
+ break;
+ default:
+ /* TODO: Userspace tracing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ goto error;
+ }
+
+ ret = LTTCOMM_OK;
+
+error:
+ return ret;
+}
+
+/*
+ * Command LTTNG_ENABLE_EVENT processed by the client thread.
+ */
+static int cmd_enable_event(struct ltt_session *session, int domain,
+ char *channel_name, struct lttng_event *event)
+{
+ int ret;
+ struct ltt_kernel_channel *kchan;
+
+ switch (domain) {
+ case LTTNG_DOMAIN_KERNEL:
+ kchan = trace_kernel_get_channel_by_name(channel_name,
+ session->kernel_session);
+ if (kchan == NULL) {
+ /* This call will notify the kernel thread */
+ ret = channel_kernel_create(session->kernel_session, channel_name,
+ NULL, kernel_poll_pipe[1]);
+ if (ret != LTTCOMM_OK) {
+ goto error;
+ }
+ }
+
+ /* Get the newly created kernel channel pointer */
+ kchan = trace_kernel_get_channel_by_name(channel_name,
+ session->kernel_session);
+ if (kchan == NULL) {
+ /* This sould not happen... */
+ ret = LTTCOMM_FATAL;
+ goto error;
+ }
+
+ ret = event_kernel_enable(session->kernel_session, kchan, event);
+ if (ret != LTTCOMM_OK) {
+ goto error;
+ }
+
+ kernel_wait_quiescent(kernel_tracer_fd);
+ break;
+ default:
+ /* TODO: Userspace tracing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ goto error;
+ }
+
+ ret = LTTCOMM_OK;
+
+error:
+ return ret;
+}
+
+/*
+ * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
+ */
+static int cmd_enable_event_all(struct ltt_session *session, int domain,
+ char *channel_name, int event_type)
+{
+ int ret;
+ struct ltt_kernel_channel *kchan;
+
+ switch (domain) {
+ case LTTNG_DOMAIN_KERNEL:
+ kchan = trace_kernel_get_channel_by_name(channel_name,
+ session->kernel_session);
+ if (kchan == NULL) {
+ /* This call will notify the kernel thread */
+ ret = channel_kernel_create(session->kernel_session, channel_name,
+ NULL, kernel_poll_pipe[1]);
+ if (ret != LTTCOMM_OK) {
+ goto error;
+ }
+ }
+
+ /* Get the newly created kernel channel pointer */
+ kchan = trace_kernel_get_channel_by_name(channel_name,
+ session->kernel_session);
+ if (kchan == NULL) {
+ /* This sould not happen... */
+ ret = LTTCOMM_FATAL;
+ goto error;
+ }
+
+ if (event_type == LTTNG_KERNEL_SYSCALL) {
+ ret = event_kernel_enable_syscalls(session->kernel_session,
+ kchan, kernel_tracer_fd);
+ } else {
+ /*
+ * This call enables all LTTNG_KERNEL_TRACEPOINTS and events
+ * already registered to the channel.
+ */
+ ret = event_kernel_enable_all(session->kernel_session,
+ kchan, kernel_tracer_fd);
+ }
+
+ if (ret != LTTCOMM_OK) {
+ goto error;
+ }
+
+ kernel_wait_quiescent(kernel_tracer_fd);
+ break;
+ default:
+ /* TODO: Userspace tracing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ goto error;
+ }
+
+ ret = LTTCOMM_OK;
+
+error:
+ return ret;
+}
+
+/*
+ * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
+ */
+static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
+{
+ int ret;
+ ssize_t nb_events = 0;
+
+ switch (domain) {
+ case LTTNG_DOMAIN_KERNEL:
+ nb_events = kernel_list_events(kernel_tracer_fd, events);
+ if (nb_events < 0) {
+ ret = LTTCOMM_KERN_LIST_FAIL;
+ goto error;
+ }
+ break;
+ default:
+ /* TODO: Userspace listing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ goto error;
+ }
+
+ return nb_events;
+
+error:
+ /* Return negative value to differentiate return code */
+ return -ret;
+}
+
+/*
+ * Command LTTNG_START_TRACE processed by the client thread.
+ */
+static int cmd_start_trace(struct ltt_session *session)
+{
+ int ret;
+ struct ltt_kernel_channel *kchan;
+ struct ltt_kernel_session *ksession;
+
+ /* Short cut */
+ ksession = session->kernel_session;
+
+ /* Kernel tracing */
+ if (ksession != NULL) {
+ /* Open kernel metadata */
+ if (ksession->metadata == NULL) {
+ ret = kernel_open_metadata(ksession, ksession->trace_path);
+ if (ret < 0) {
+ ret = LTTCOMM_KERN_META_FAIL;
+ goto error;
+ }
+ }
+
+ /* Open kernel metadata stream */
+ if (ksession->metadata_stream_fd == 0) {
+ ret = kernel_open_metadata_stream(ksession);
+ if (ret < 0) {
+ ERR("Kernel create metadata stream failed");
+ ret = LTTCOMM_KERN_STREAM_FAIL;
+ goto error;
+ }
}
- /* Kernel tracing */
- if (cmd_ctx->session->kernel_session != NULL) {
- if (cmd_ctx->session->kernel_session->metadata == NULL) {
- DBG("Open kernel metadata");
- ret = kernel_open_metadata(cmd_ctx->session->kernel_session,
- cmd_ctx->session->path);
+ /* For each channel */
+ cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
+ if (kchan->stream_count == 0) {
+ ret = kernel_open_channel_stream(kchan);
if (ret < 0) {
- ret = LTTCOMM_KERN_META_FAIL;
+ ret = LTTCOMM_KERN_STREAM_FAIL;
goto error;
}
+ /* Update the stream global counter */
+ ksession->stream_count_global += ret;
}
+ }
- if (cmd_ctx->session->kernel_session->metadata_stream_fd == 0) {
- DBG("Opening kernel metadata stream");
- if (cmd_ctx->session->kernel_session->metadata_stream_fd == 0) {
- ret = kernel_open_metadata_stream(cmd_ctx->session->kernel_session);
- if (ret < 0) {
- ERR("Kernel create metadata stream failed");
- ret = LTTCOMM_KERN_STREAM_FAIL;
- goto error;
- }
- }
- }
+ /* Setup kernel consumer socket and send fds to it */
+ ret = init_kernel_tracing(ksession);
+ if (ret < 0) {
+ ret = LTTCOMM_KERN_START_FAIL;
+ goto error;
+ }
- /* For each channel */
- cds_list_for_each_entry(chan, &cmd_ctx->session->kernel_session->channel_list.head, list) {
- if (chan->stream_count == 0) {
- ret = kernel_open_channel_stream(chan);
- if (ret < 0) {
- ERR("Kernel create channel stream failed");
- ret = LTTCOMM_KERN_STREAM_FAIL;
- goto error;
- }
- /* Update the stream global counter */
- cmd_ctx->session->kernel_session->stream_count_global += ret;
- }
- }
+ /* This start the kernel tracing */
+ ret = kernel_start_session(ksession);
+ if (ret < 0) {
+ ret = LTTCOMM_KERN_START_FAIL;
+ goto error;
+ }
- DBG("Start kernel tracing");
- ret = kernel_start_session(cmd_ctx->session->kernel_session);
- if (ret < 0) {
- ERR("Kernel start session failed");
- ret = LTTCOMM_KERN_START_FAIL;
- goto error;
- }
+ /* Quiescent wait after starting trace */
+ kernel_wait_quiescent(kernel_tracer_fd);
+ }
+
+ /* TODO: Start all UST traces */
+
+ ret = LTTCOMM_OK;
+
+error:
+ return ret;
+}
- ret = start_kernel_trace(cmd_ctx->session->kernel_session);
+/*
+ * Command LTTNG_STOP_TRACE processed by the client thread.
+ */
+static int cmd_stop_trace(struct ltt_session *session)
+{
+ int ret;
+ struct ltt_kernel_channel *kchan;
+ struct ltt_kernel_session *ksession;
+
+ /* Short cut */
+ ksession = session->kernel_session;
+
+ /* Kernel tracer */
+ if (ksession != NULL) {
+ DBG("Stop kernel tracing");
+
+ /* Flush all buffers before stopping */
+ ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
+ if (ret < 0) {
+ ERR("Kernel metadata flush failed");
+ }
+
+ cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
+ ret = kernel_flush_buffer(kchan);
if (ret < 0) {
- ret = LTTCOMM_KERN_START_FAIL;
- goto error;
+ ERR("Kernel flush buffer error");
}
+ }
- /* Quiescent wait after starting trace */
- kernel_wait_quiescent(kernel_tracer_fd);
+ ret = kernel_stop_session(ksession);
+ if (ret < 0) {
+ ret = LTTCOMM_KERN_STOP_FAIL;
+ goto error;
}
- /* TODO: Start all UST traces */
+ kernel_wait_quiescent(kernel_tracer_fd);
+ }
+
+ /* TODO : User-space tracer */
- ret = LTTCOMM_OK;
- break;
+ ret = LTTCOMM_OK;
+
+error:
+ return ret;
+}
+
+/*
+ * Command LTTNG_CREATE_SESSION processed by the client thread.
+ */
+static int cmd_create_session(char *name, char *path)
+{
+ int ret;
+
+ ret = session_create(name, path);
+ if (ret != LTTCOMM_OK) {
+ goto error;
}
- case LTTNG_STOP_TRACE:
+
+ ret = LTTCOMM_OK;
+
+error:
+ return ret;
+}
+
+/*
+ * Command LTTNG_DESTROY_SESSION processed by the client thread.
+ */
+static int cmd_destroy_session(struct ltt_session *session, char *name)
+{
+ int ret;
+
+ /* Clean kernel session teardown */
+ teardown_kernel_session(session);
+
+ /*
+ * Must notify the kernel thread here to update it's poll setin order
+ * to remove the channel(s)' fd just destroyed.
+ */
+ ret = notify_thread_pipe(kernel_poll_pipe[1]);
+ if (ret < 0) {
+ perror("write kernel poll pipe");
+ }
+
+ ret = session_destroy(name);
+
+ return ret;
+}
+
+/*
+ * Command LTTNG_CALIBRATE processed by the client thread.
+ */
+static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
+{
+ int ret;
+
+ switch (domain) {
+ case LTTNG_DOMAIN_KERNEL:
{
- struct ltt_kernel_channel *chan;
+ struct lttng_kernel_calibrate kcalibrate;
+
+ kcalibrate.type = calibrate->type;
+ ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
+ if (ret < 0) {
+ ret = LTTCOMM_KERN_ENABLE_FAIL;
+ goto error;
+ }
+ break;
+ }
+ default:
+ /* TODO: Userspace tracing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ goto error;
+ }
+
+ ret = LTTCOMM_OK;
+
+error:
+ return ret;
+}
+
+/*
+ * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
+ */
+static int cmd_register_consumer(struct ltt_session *session, int domain,
+ char *sock_path)
+{
+ int ret, sock;
+
+ switch (domain) {
+ case LTTNG_DOMAIN_KERNEL:
+ /* Can't register a consumer if there is already one */
+ if (session->kernel_session->consumer_fd != 0) {
+ ret = LTTCOMM_KERN_CONSUMER_FAIL;
+ goto error;
+ }
+
+ sock = lttcomm_connect_unix_sock(sock_path);
+ if (sock < 0) {
+ ret = LTTCOMM_CONNECT_FAIL;
+ goto error;
+ }
+
+ session->kernel_session->consumer_fd = sock;
+ break;
+ default:
+ /* TODO: Userspace tracing */
+ ret = LTTCOMM_NOT_IMPLEMENTED;
+ goto error;
+ }
+
+ ret = LTTCOMM_OK;
+
+error:
+ return ret;
+}
+
+/*
+ * Command LTTNG_LIST_DOMAINS processed by the client thread.
+ */
+static ssize_t cmd_list_domains(struct ltt_session *session,
+ struct lttng_domain **domains)
+{
+ int ret;
+ ssize_t nb_dom = 0;
+
+ if (session->kernel_session != NULL) {
+ nb_dom++;
+ }
+
+ nb_dom += session->ust_session_list.count;
+
+ *domains = malloc(nb_dom * sizeof(struct lttng_domain));
+ if (*domains == NULL) {
+ ret = -LTTCOMM_FATAL;
+ goto error;
+ }
+
+ (*domains)[0].type = LTTNG_DOMAIN_KERNEL;
+
+ /* TODO: User-space tracer domain support */
+
+ return nb_dom;
+
+error:
+ return ret;
+}
+
+/*
+ * Command LTTNG_LIST_CHANNELS processed by the client thread.
+ */
+static ssize_t cmd_list_channels(struct ltt_session *session,
+ struct lttng_channel **channels)
+{
+ int ret;
+ ssize_t nb_chan = 0;
+
+ if (session->kernel_session != NULL) {
+ nb_chan += session->kernel_session->channel_count;
+ }
+
+ *channels = malloc(nb_chan * sizeof(struct lttng_channel));
+ if (*channels == NULL) {
+ ret = -LTTCOMM_FATAL;
+ goto error;
+ }
+
+ list_lttng_channels(session, *channels);
+
+ return nb_chan;
+
+error:
+ return ret;
+}
+
+/*
+ * Command LTTNG_LIST_EVENTS processed by the client thread.
+ */
+static ssize_t cmd_list_events(struct ltt_session *session,
+ char *channel_name, struct lttng_event **events)
+{
+ int ret;
+ ssize_t nb_event = 0;
+ struct ltt_kernel_channel *kchan = NULL;
+
+ if (session->kernel_session != NULL) {
+ kchan = trace_kernel_get_channel_by_name(channel_name,
+ session->kernel_session);
+ if (kchan == NULL) {
+ ret = -LTTCOMM_KERN_CHAN_NOT_FOUND;
+ goto error;
+ }
+ nb_event += kchan->event_count;
+ }
+
+ *events = malloc(nb_event * sizeof(struct lttng_event));
+ if (*events == NULL) {
+ ret = -LTTCOMM_FATAL;
+ goto error;
+ }
+
+ list_lttng_events(kchan, *events);
+
+ /* TODO: User-space tracer support */
+
+ return nb_event;
+
+error:
+ return ret;
+}
+
+/*
+ * Process the command requested by the lttng client within the command
+ * context structure. This function make sure that the return structure (llm)
+ * is set and ready for transmission before returning.
+ *
+ * Return any error encountered or 0 for success.
+ */
+static int process_client_msg(struct command_ctx *cmd_ctx)
+{
+ int ret = LTTCOMM_OK;
+ int need_kernel_session = 1;
+
+ DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
+
+ /*
+ * Check for command that don't needs to allocate a returned payload. We do
+ * this here so we don't have to make the call for no payload" at each
+ * command.
+ */
+ switch(cmd_ctx->lsm->cmd_type) {
+ case LTTNG_LIST_SESSIONS:
+ case LTTNG_LIST_TRACEPOINTS:
+ case LTTNG_LIST_DOMAINS:
+ case LTTNG_LIST_CHANNELS:
+ case LTTNG_LIST_EVENTS:
+ break;
+ default:
/* Setup lttng message with no payload */
ret = setup_lttng_msg(cmd_ctx, 0);
if (ret < 0) {
- goto setup_error;
+ /* This label does not try to unlock the session */
+ goto init_setup_error;
}
+ }
- /* Kernel tracer */
- if (cmd_ctx->session->kernel_session != NULL) {
- DBG("Stop kernel tracing");
+ /* Commands that DO NOT need a session. */
+ switch (cmd_ctx->lsm->cmd_type) {
+ case LTTNG_CALIBRATE:
+ case LTTNG_CREATE_SESSION:
+ case LTTNG_LIST_SESSIONS:
+ case LTTNG_LIST_TRACEPOINTS:
+ need_kernel_session = 0;
+ break;
+ default:
+ DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
+ cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
+ if (cmd_ctx->session == NULL) {
+ if (cmd_ctx->lsm->session.name != NULL) {
+ ret = LTTCOMM_SESS_NOT_FOUND;
+ } else {
+ /* If no session name specified */
+ ret = LTTCOMM_SELECT_SESS;
+ }
+ goto error;
+ } else {
+ /* Acquire lock for the session */
+ session_lock(cmd_ctx->session);
+ }
+ break;
+ }
- ret = kernel_metadata_flush_buffer(cmd_ctx->session->kernel_session->metadata_stream_fd);
- if (ret < 0) {
- ERR("Kernel metadata flush failed");
+ /*
+ * Check domain type for specific "pre-action".
+ */
+ switch (cmd_ctx->lsm->domain.type) {
+ case LTTNG_DOMAIN_KERNEL:
+ /* Kernel tracer check */
+ if (kernel_tracer_fd == 0) {
+ /* Basically, load kernel tracer modules */
+ init_kernel_tracer();
+ if (kernel_tracer_fd == 0) {
+ ret = LTTCOMM_KERN_NA;
+ goto error;
}
+ }
- cds_list_for_each_entry(chan, &cmd_ctx->session->kernel_session->channel_list.head, list) {
- ret = kernel_flush_buffer(chan);
+ /* Need a session for kernel command */
+ if (need_kernel_session) {
+ if (cmd_ctx->session->kernel_session == NULL) {
+ ret = create_kernel_session(cmd_ctx->session);
if (ret < 0) {
- ERR("Kernel flush buffer error");
+ ret = LTTCOMM_KERN_SESS_FAIL;
+ goto error;
}
}
- ret = kernel_stop_session(cmd_ctx->session->kernel_session);
- if (ret < 0) {
- ERR("Kernel stop session failed");
- ret = LTTCOMM_KERN_STOP_FAIL;
- goto error;
+ /* Start the kernel consumer daemon */
+ if (kconsumerd_pid == 0 &&
+ cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
+ ret = start_kconsumerd();
+ if (ret < 0) {
+ ret = LTTCOMM_KERN_CONSUMER_FAIL;
+ goto error;
+ }
}
-
- /* Quiescent wait after stopping trace */
- kernel_wait_quiescent(kernel_tracer_fd);
}
+ break;
+ default:
+ /* TODO Userspace tracer */
+ break;
+ }
- /* TODO : User-space tracer */
-
+ /* Process by command type */
+ switch (cmd_ctx->lsm->cmd_type) {
+ case LTTNG_ADD_CONTEXT:
+ {
+ ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
+ cmd_ctx->lsm->u.context.channel_name,
+ cmd_ctx->lsm->u.context.event_name,
+ &cmd_ctx->lsm->u.context.ctx);
+ break;
+ }
+ case LTTNG_DISABLE_CHANNEL:
+ {
+ ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
+ cmd_ctx->lsm->u.disable.channel_name);
+ break;
+ }
+ case LTTNG_DISABLE_EVENT:
+ {
+ ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
+ cmd_ctx->lsm->u.disable.channel_name,
+ cmd_ctx->lsm->u.disable.name);
ret = LTTCOMM_OK;
break;
}
- case LTTNG_CREATE_SESSION:
+ case LTTNG_DISABLE_ALL_EVENT:
+ {
+ DBG("Disabling all kernel event");
+
+ ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
+ cmd_ctx->lsm->u.disable.channel_name);
+ break;
+ }
+ case LTTNG_ENABLE_CHANNEL:
+ {
+ ret = cmd_enable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
+ cmd_ctx->lsm->u.enable.channel_name,
+ &cmd_ctx->lsm->u.channel.chan);
+ break;
+ }
+ case LTTNG_ENABLE_EVENT:
{
- /* Setup lttng message with no payload */
- ret = setup_lttng_msg(cmd_ctx, 0);
- if (ret < 0) {
- goto setup_error;
- }
-
- ret = create_session(cmd_ctx->lsm->session_name, cmd_ctx->lsm->path);
- if (ret < 0) {
- if (ret == -EEXIST) {
- ret = LTTCOMM_EXIST_SESS;
- } else {
- ret = LTTCOMM_FATAL;
- }
- goto error;
- }
-
- ret = LTTCOMM_OK;
+ ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
+ cmd_ctx->lsm->u.enable.channel_name,
+ &cmd_ctx->lsm->u.enable.event);
break;
}
- case LTTNG_DESTROY_SESSION:
+ case LTTNG_ENABLE_ALL_EVENT:
{
- /* Setup lttng message with no payload */
- ret = setup_lttng_msg(cmd_ctx, 0);
- if (ret < 0) {
- goto setup_error;
- }
-
- /* Clean kernel session teardown */
- teardown_kernel_session(cmd_ctx->session);
-
- ret = destroy_session(cmd_ctx->lsm->session_name);
- if (ret < 0) {
- ret = LTTCOMM_FATAL;
- goto error;
- }
+ DBG("Enabling all kernel event");
- ret = LTTCOMM_OK;
+ ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
+ cmd_ctx->lsm->u.enable.channel_name,
+ cmd_ctx->lsm->u.enable.event.type);
break;
}
- /*
- case LTTNG_LIST_TRACES:
+ case LTTNG_LIST_TRACEPOINTS:
{
- unsigned int trace_count;
+ struct lttng_event *events;
+ ssize_t nb_events;
- trace_count = get_trace_count_per_session(cmd_ctx->session);
- if (trace_count == 0) {
- ret = LTTCOMM_NO_TRACE;
+ nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
+ if (nb_events < 0) {
+ ret = -nb_events;
goto error;
}
- ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_trace) * trace_count);
+ /*
+ * Setup lttng message with payload size set to the event list size in
+ * bytes and then copy list into the llm payload.
+ */
+ ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
if (ret < 0) {
+ free(events);
goto setup_error;
}
- get_traces_per_session(cmd_ctx->session,
- (struct lttng_trace *)(cmd_ctx->llm->payload));
+ /* Copy event list into message payload */
+ memcpy(cmd_ctx->llm->payload, events,
+ sizeof(struct lttng_event) * nb_events);
+
+ free(events);
ret = LTTCOMM_OK;
break;
}
- */
- /*
- case UST_CREATE_TRACE:
+ case LTTNG_START_TRACE:
{
- ret = setup_lttng_msg(cmd_ctx, 0);
- if (ret < 0) {
- goto setup_error;
- }
-
- ret = ust_create_trace(cmd_ctx);
- if (ret < 0) {
- goto error;
- }
+ ret = cmd_start_trace(cmd_ctx->session);
+ break;
+ }
+ case LTTNG_STOP_TRACE:
+ {
+ ret = cmd_stop_trace(cmd_ctx->session);
+ break;
+ }
+ case LTTNG_CREATE_SESSION:
+ {
+ ret = cmd_create_session(cmd_ctx->lsm->session.name,
+ cmd_ctx->lsm->session.path);
+ break;
+ }
+ case LTTNG_DESTROY_SESSION:
+ {
+ ret = cmd_destroy_session(cmd_ctx->session,
+ cmd_ctx->lsm->session.name);
break;
}
- */
- case LTTNG_LIST_TRACEABLE_APPS:
+ case LTTNG_LIST_DOMAINS:
{
- unsigned int app_count;
+ ssize_t nb_dom;
+ struct lttng_domain *domains;
- app_count = get_app_count();
- DBG("Traceable application count : %d", app_count);
- if (app_count == 0) {
- ret = LTTCOMM_NO_APPS;
+ nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
+ if (nb_dom < 0) {
+ ret = -nb_dom;
goto error;
}
- ret = setup_lttng_msg(cmd_ctx, sizeof(pid_t) * app_count);
+ ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
if (ret < 0) {
goto setup_error;
}
- get_app_list_pids((pid_t *)(cmd_ctx->llm->payload));
+ /* Copy event list into message payload */
+ memcpy(cmd_ctx->llm->payload, domains,
+ nb_dom * sizeof(struct lttng_domain));
+
+ free(domains);
ret = LTTCOMM_OK;
break;
}
- /*
- case UST_START_TRACE:
+ case LTTNG_LIST_CHANNELS:
{
- ret = setup_lttng_msg(cmd_ctx, 0);
- if (ret < 0) {
- goto setup_error;
+ size_t nb_chan;
+ struct lttng_channel *channels;
+
+ nb_chan = cmd_list_channels(cmd_ctx->session, &channels);
+ if (nb_chan < 0) {
+ ret = -nb_chan;
+ goto error;
}
- ret = ust_start_trace(cmd_ctx);
+ ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
if (ret < 0) {
goto setup_error;
}
+
+ /* Copy event list into message payload */
+ memcpy(cmd_ctx->llm->payload, channels,
+ nb_chan * sizeof(struct lttng_channel));
+
+ free(channels);
+
+ ret = LTTCOMM_OK;
break;
}
- case UST_STOP_TRACE:
+ case LTTNG_LIST_EVENTS:
{
- ret = setup_lttng_msg(cmd_ctx, 0);
- if (ret < 0) {
- goto setup_error;
+ size_t nb_event;
+ struct lttng_event *events = NULL;
+
+ nb_event = cmd_list_events(cmd_ctx->session,
+ cmd_ctx->lsm->u.list.channel_name, &events);
+ if (nb_event < 0) {
+ ret = -nb_event;
+ goto error;
}
- ret = ust_stop_trace(cmd_ctx);
+ ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
if (ret < 0) {
goto setup_error;
}
+
+ /* Copy event list into message payload */
+ memcpy(cmd_ctx->llm->payload, events,
+ nb_event * sizeof(struct lttng_event));
+
+ free(events);
+
+ ret = LTTCOMM_OK;
break;
}
- */
case LTTNG_LIST_SESSIONS:
{
- unsigned int session_count;
+ session_lock_list();
- session_count = get_session_count();
- if (session_count == 0) {
+ if (session_list_ptr->count == 0) {
ret = LTTCOMM_NO_SESSION;
+ session_unlock_list();
goto error;
}
- ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * session_count);
+ ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) *
+ session_list_ptr->count);
if (ret < 0) {
+ session_unlock_list();
goto setup_error;
}
- get_lttng_session((struct lttng_session *)(cmd_ctx->llm->payload));
+ /* Filled the session array */
+ list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload));
+
+ session_unlock_list();
ret = LTTCOMM_OK;
break;
}
+ case LTTNG_CALIBRATE:
+ {
+ ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
+ &cmd_ctx->lsm->u.calibrate);
+ break;
+ }
+ case LTTNG_REGISTER_CONSUMER:
+ {
+ ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
+ cmd_ctx->lsm->u.reg.path);
+ break;
+ }
default:
- /* Undefined command */
- ret = setup_lttng_msg(cmd_ctx, 0);
- if (ret < 0) {
- goto setup_error;
- }
-
ret = LTTCOMM_UND;
break;
}
- /* Set return code */
- cmd_ctx->llm->ret_code = ret;
-
- return ret;
-
error:
if (cmd_ctx->llm == NULL) {
DBG("Missing llm structure. Allocating one.");
goto setup_error;
}
}
- /* Notify client of error */
+ /* Set return code */
cmd_ctx->llm->ret_code = ret;
-
setup_error:
+ if (cmd_ctx->session) {
+ session_unlock(cmd_ctx->session);
+ }
+init_setup_error:
return ret;
}
/*
- * thread_manage_clients
- *
- * This thread manage all clients request using the unix
- * client socket for communication.
+ * This thread manage all clients request using the unix client socket for
+ * communication.
*/
static void *thread_manage_clients(void *data)
{
- int sock, ret;
- struct command_ctx *cmd_ctx;
+ int sock = 0, ret, i, pollfd;
+ uint32_t revents, nb_fd;
+ struct command_ctx *cmd_ctx = NULL;
+ struct lttng_poll_event events;
DBG("[thread] Manage client started");
goto error;
}
- /* Notify parent pid that we are ready
- * to accept command for client side.
+ /*
+ * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
+ * more will be added to this poll set.
+ */
+ ret = create_thread_poll_set(&events, 2);
+ if (ret < 0) {
+ goto error;
+ }
+
+ /* Add the application registration socket */
+ ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
+ if (ret < 0) {
+ goto error;
+ }
+
+ /*
+ * Notify parent pid that we are ready to accept command for client side.
*/
if (opt_sig_parent) {
kill(ppid, SIGCHLD);
}
while (1) {
- /* Blocking call, waiting for transmission */
DBG("Accepting client command ...");
+
+ nb_fd = LTTNG_POLL_GETNB(&events);
+
+ /* Inifinite blocking call, waiting for transmission */
+ ret = lttng_poll_wait(&events, -1);
+ if (ret < 0) {
+ goto error;
+ }
+
+ for (i = 0; i < nb_fd; i++) {
+ /* Fetch once the poll data */
+ revents = LTTNG_POLL_GETEV(&events, i);
+ pollfd = LTTNG_POLL_GETFD(&events, i);
+
+ /* Thread quit pipe has been closed. Killing thread. */
+ ret = check_thread_quit_pipe(pollfd, revents);
+ if (ret) {
+ goto error;
+ }
+
+ /* Event on the registration socket */
+ if (pollfd == client_sock) {
+ if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
+ ERR("Client socket poll error");
+ goto error;
+ }
+ }
+ }
+
+ DBG("Wait for client response");
+
sock = lttcomm_accept_unix_sock(client_sock);
if (sock < 0) {
goto error;
/* Allocate context command to process the client request */
cmd_ctx = malloc(sizeof(struct command_ctx));
+ if (cmd_ctx == NULL) {
+ perror("malloc cmd_ctx");
+ goto error;
+ }
/* Allocate data buffer for reception */
cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg));
+ if (cmd_ctx->lsm == NULL) {
+ perror("malloc cmd_ctx->lsm");
+ goto error;
+ }
+
cmd_ctx->llm = NULL;
cmd_ctx->session = NULL;
* the client.
*/
DBG("Receiving data from client ...");
- ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm, sizeof(struct lttcomm_session_msg));
+ ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm,
+ sizeof(struct lttcomm_session_msg));
if (ret <= 0) {
+ DBG("Nothing recv() from client... continuing");
+ close(sock);
+ free(cmd_ctx);
continue;
}
- // TODO: Validate cmd_ctx including sanity check for security purpose.
+ // TODO: Validate cmd_ctx including sanity check for
+ // security purpose.
/*
* This function dispatch the work to the kernel or userspace tracer
*/
ret = process_client_msg(cmd_ctx);
if (ret < 0) {
- /* TODO: Inform client somehow of the fatal error. At this point,
- * ret < 0 means that a malloc failed (ENOMEM). */
- /* Error detected but still accept command */
- clean_command_ctx(cmd_ctx);
+ /*
+ * TODO: Inform client somehow of the fatal error. At
+ * this point, ret < 0 means that a malloc failed
+ * (ENOMEM). Error detected but still accept command.
+ */
+ clean_command_ctx(&cmd_ctx);
continue;
}
- DBG("Sending response (size: %d, retcode: %d)",
- cmd_ctx->lttng_msg_size, cmd_ctx->llm->ret_code);
+ DBG("Sending response (size: %d, retcode: %s)",
+ cmd_ctx->lttng_msg_size,
+ lttng_get_readable_code(-cmd_ctx->llm->ret_code));
ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
if (ret < 0) {
ERR("Failed to send data back to client");
}
- clean_command_ctx(cmd_ctx);
+ clean_command_ctx(&cmd_ctx);
/* End of transmission */
close(sock);
}
error:
+ DBG("Client thread dying");
+ unlink(client_unix_sock_path);
+ close(client_sock);
+ close(sock);
+
+ lttng_poll_clean(&events);
+ clean_command_ctx(&cmd_ctx);
return NULL;
}
fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
fprintf(stderr, " -q, --quiet No output at all.\n");
fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
+ fprintf(stderr, " --verbose-kconsumerd Verbose mode for kconsumerd. Activate DBG() macro.\n");
}
/*
{ "version", 0, 0, 'V' },
{ "quiet", 0, 0, 'q' },
{ "verbose", 0, 0, 'v' },
+ { "verbose-kconsumerd", 0, 0, 'Z' },
{ NULL, 0, 0, 0 }
};
while (1) {
int option_index = 0;
- c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:E:C:", long_options, &option_index);
+ c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:E:C:Z",
+ long_options, &option_index);
if (c == -1) {
break;
}
opt_quiet = 1;
break;
case 'v':
- opt_verbose = 1;
+ /* Verbose level can increase using multiple -v */
+ opt_verbose += 1;
+ break;
+ case 'Z':
+ opt_verbose_kconsumerd += 1;
break;
default:
/* Unknown option or other error.
}
/*
- * init_daemon_socket
- *
- * Creates the two needed socket by the daemon.
+ * Creates the two needed socket by the daemon.
* apps_sock - The communication socket for all UST apps.
* client_sock - The communication of the cli tool (lttng).
*/
-static int init_daemon_socket()
+static int init_daemon_socket(void)
{
int ret = 0;
mode_t old_umask;
}
/* File permission MUST be 666 */
- ret = chmod(apps_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
+ ret = chmod(apps_unix_sock_path,
+ S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
if (ret < 0) {
ERR("Set file permissions failed: %s", apps_unix_sock_path);
perror("chmod");
}
/*
- * check_existing_daemon
- *
- * Check if the global socket is available.
- * If yes, error is returned.
+ * Check if the global socket is available, and if a daemon is answering at the
+ * other side. If yes, error is returned.
*/
-static int check_existing_daemon()
+static int check_existing_daemon(void)
{
- int ret;
-
- ret = access(client_unix_sock_path, F_OK);
- if (ret == 0) {
- ret = access(apps_unix_sock_path, F_OK);
+ if (access(client_unix_sock_path, F_OK) < 0 &&
+ access(apps_unix_sock_path, F_OK) < 0) {
+ return 0;
}
- return ret;
+ /* Is there anybody out there ? */
+ if (lttng_session_daemon_alive()) {
+ return -EEXIST;
+ } else {
+ return 0;
+ }
}
/*
- * set_permissions
- *
- * Set the tracing group gid onto the client socket.
+ * Set the tracing group gid onto the client socket.
*
- * Race window between mkdir and chown is OK because we are going from
- * more permissive (root.root) to les permissive (root.tracing).
+ * Race window between mkdir and chown is OK because we are going from more
+ * permissive (root.root) to les permissive (root.tracing).
*/
static int set_permissions(void)
{
int ret;
- struct group *grp;
-
- /* Decide which group name to use */
- (opt_tracing_group != NULL) ?
- (grp = getgrnam(opt_tracing_group)) :
- (grp = getgrnam(default_tracing_group));
+ gid_t gid;
- if (grp == NULL) {
+ gid = allowed_group();
+ if (gid < 0) {
if (is_root) {
WARN("No tracing group detected");
ret = 0;
}
/* Set lttng run dir */
- ret = chown(LTTNG_RUNDIR, 0, grp->gr_gid);
+ ret = chown(LTTNG_RUNDIR, 0, gid);
if (ret < 0) {
ERR("Unable to set group on " LTTNG_RUNDIR);
perror("chown");
}
/* lttng client socket path */
- ret = chown(client_unix_sock_path, 0, grp->gr_gid);
+ ret = chown(client_unix_sock_path, 0, gid);
if (ret < 0) {
ERR("Unable to set group on %s", client_unix_sock_path);
perror("chown");
}
/* kconsumerd error socket path */
- ret = chown(kconsumerd_err_unix_sock_path, 0, grp->gr_gid);
+ ret = chown(kconsumerd_err_unix_sock_path, 0, gid);
if (ret < 0) {
ERR("Unable to set group on %s", kconsumerd_err_unix_sock_path);
perror("chown");
}
/*
- * create_lttng_rundir
- *
- * Create the lttng run directory needed for all
- * global sockets and pipe.
+ * Create the pipe used to wake up the kernel thread.
+ */
+static int create_kernel_poll_pipe(void)
+{
+ return pipe2(kernel_poll_pipe, O_CLOEXEC);
+}
+
+/*
+ * Create the application command pipe to wake thread_manage_apps.
+ */
+static int create_apps_cmd_pipe(void)
+{
+ return pipe2(apps_cmd_pipe, O_CLOEXEC);
+}
+
+/*
+ * Create the lttng run directory needed for all global sockets and pipe.
*/
static int create_lttng_rundir(void)
{
}
/*
- * set_kconsumerd_sockets
- *
- * Setup sockets and directory needed by the kconsumerd
- * communication with the session daemon.
+ * Setup sockets and directory needed by the kconsumerd communication with the
+ * session daemon.
*/
static int set_kconsumerd_sockets(void)
{
int ret;
if (strlen(kconsumerd_err_unix_sock_path) == 0) {
- snprintf(kconsumerd_err_unix_sock_path, PATH_MAX, KCONSUMERD_ERR_SOCK_PATH);
+ snprintf(kconsumerd_err_unix_sock_path, PATH_MAX,
+ KCONSUMERD_ERR_SOCK_PATH);
}
if (strlen(kconsumerd_cmd_unix_sock_path) == 0) {
- snprintf(kconsumerd_cmd_unix_sock_path, PATH_MAX, KCONSUMERD_CMD_SOCK_PATH);
+ snprintf(kconsumerd_cmd_unix_sock_path, PATH_MAX,
+ KCONSUMERD_CMD_SOCK_PATH);
}
ret = mkdir(KCONSUMERD_PATH, S_IRWXU | S_IRWXG);
}
/* Create the kconsumerd error unix socket */
- kconsumerd_err_sock = lttcomm_create_unix_sock(kconsumerd_err_unix_sock_path);
+ kconsumerd_err_sock =
+ lttcomm_create_unix_sock(kconsumerd_err_unix_sock_path);
if (kconsumerd_err_sock < 0) {
ERR("Create unix sock failed: %s", kconsumerd_err_unix_sock_path);
ret = -1;
}
/* File permission MUST be 660 */
- ret = chmod(kconsumerd_err_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
+ ret = chmod(kconsumerd_err_unix_sock_path,
+ S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
if (ret < 0) {
ERR("Set file permissions failed: %s", kconsumerd_err_unix_sock_path);
perror("chmod");
}
/*
- * sighandler
+ * Signal handler for the daemon
*
- * Signal handler for the daemon
+ * Simply stop all worker threads, leaving main() return gracefully after
+ * joining all threads and calling cleanup().
*/
static void sighandler(int sig)
{
switch (sig) {
- case SIGPIPE:
- DBG("SIGPIPE catched");
- return;
- case SIGINT:
- DBG("SIGINT catched");
- cleanup();
- break;
- case SIGTERM:
- DBG("SIGTERM catched");
- cleanup();
- break;
- default:
- break;
+ case SIGPIPE:
+ DBG("SIGPIPE catched");
+ return;
+ case SIGINT:
+ DBG("SIGINT catched");
+ stop_threads();
+ break;
+ case SIGTERM:
+ DBG("SIGTERM catched");
+ stop_threads();
+ break;
+ default:
+ break;
}
-
- exit(EXIT_SUCCESS);
}
/*
- * set_signal_handler
- *
- * Setup signal handler for :
+ * Setup signal handler for :
* SIGINT, SIGTERM, SIGPIPE
*/
static int set_signal_handler(void)
}
/*
- * set_ulimit
- *
- * Set open files limit to unlimited. This daemon can open a large number of
- * file descriptors in order to consumer multiple kernel traces.
+ * Set open files limit to unlimited. This daemon can open a large number of
+ * file descriptors in order to consumer multiple kernel traces.
*/
static void set_ulimit(void)
{
int ret;
struct rlimit lim;
+ /* The kernel does not allowed an infinite limit for open files */
lim.rlim_cur = 65535;
lim.rlim_max = 65535;
void *status;
const char *home_path;
+ /* Create thread quit pipe */
+ if ((ret = init_thread_quit_pipe()) < 0) {
+ goto error;
+ }
+
/* Parse arguments */
progname = argv[0];
if ((ret = parse_args(argc, argv) < 0)) {
/* Check if daemon is UID = 0 */
is_root = !getuid();
- /* Set all sockets path */
if (is_root) {
ret = create_lttng_rundir();
if (ret < 0) {
DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
}
- ret = set_kconsumerd_sockets();
- if (ret < 0) {
- goto error;
+ /* Set global SHM for ust */
+ if (strlen(wait_shm_path) == 0) {
+ snprintf(wait_shm_path, PATH_MAX,
+ DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
}
-
- /* Setup kernel tracer */
- init_kernel_tracer();
-
- /* Set ulimit for open files */
- set_ulimit();
} else {
home_path = get_home_dir();
if (home_path == NULL) {
- ERR("Can't get HOME directory for sockets creation.\n \
- Please specify --socket PATH.");
+ /* TODO: Add --socket PATH option */
+ ERR("Can't get HOME directory for sockets creation.");
+ ret = -EPERM;
goto error;
}
snprintf(client_unix_sock_path, PATH_MAX,
DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
}
+
+ /* Set global SHM for ust */
+ if (strlen(wait_shm_path) == 0) {
+ snprintf(wait_shm_path, PATH_MAX,
+ DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
+ }
}
DBG("Client socket path %s", client_unix_sock_path);
DBG("Application socket path %s", apps_unix_sock_path);
- /* See if daemon already exist. If any of the two
- * socket needed by the daemon are present, this test fails
+ /*
+ * See if daemon already exist.
*/
- if ((ret = check_existing_daemon()) == 0) {
+ if ((ret = check_existing_daemon()) < 0) {
ERR("Already running daemon.\n");
- /* We do not goto error because we must not
- * cleanup() because a daemon is already running.
+ /*
+ * We do not goto exit because we must not cleanup()
+ * because a daemon is already running.
*/
- exit(EXIT_FAILURE);
+ goto error;
}
- if (set_signal_handler() < 0) {
- goto error;
+ /* After this point, we can safely call cleanup() with "goto exit" */
+
+ /*
+ * These actions must be executed as root. We do that *after* setting up
+ * the sockets path because we MUST make the check for another daemon using
+ * those paths *before* trying to set the kernel consumer sockets and init
+ * kernel tracer.
+ */
+ if (is_root) {
+ ret = set_kconsumerd_sockets();
+ if (ret < 0) {
+ goto exit;
+ }
+
+ /* Setup kernel tracer */
+ init_kernel_tracer();
+
+ /* Set ulimit for open files */
+ set_ulimit();
+ }
+
+ if ((ret = set_signal_handler()) < 0) {
+ goto exit;
}
/* Setup the needed unix socket */
- if (init_daemon_socket() < 0) {
- goto error;
+ if ((ret = init_daemon_socket()) < 0) {
+ goto exit;
}
/* Set credentials to socket */
- if (is_root && (set_permissions() < 0)) {
- goto error;
+ if (is_root && ((ret = set_permissions()) < 0)) {
+ goto exit;
}
/* Get parent pid if -S, --sig-parent is specified. */
ppid = getppid();
}
- while (1) {
- /* Create thread to manage the client socket */
- ret = pthread_create(&client_thread, NULL, thread_manage_clients, (void *) NULL);
- if (ret != 0) {
- perror("pthread_create");
- goto error;
- }
+ /* Setup the kernel pipe for waking up the kernel thread */
+ if ((ret = create_kernel_poll_pipe()) < 0) {
+ goto exit;
+ }
- /* Create thread to manage application socket */
- ret = pthread_create(&apps_thread, NULL, thread_manage_apps, (void *) NULL);
- if (ret != 0) {
- perror("pthread_create");
- goto error;
- }
+ /* Setup the thread apps communication pipe. */
+ if ((ret = create_apps_cmd_pipe()) < 0) {
+ goto exit;
+ }
- ret = pthread_join(client_thread, &status);
- if (ret != 0) {
- perror("pthread_join");
- goto error;
- }
+ /* Init UST command queue. */
+ cds_wfq_init(&ust_cmd_queue.queue);
+
+ /*
+ * Get session list pointer. This pointer MUST NOT be free(). This list is
+ * statically declared in session.c
+ */
+ session_list_ptr = session_get_list();
+
+ /* Set up max poll set size */
+ lttng_poll_set_max_size();
+
+ /* Create thread to manage the client socket */
+ ret = pthread_create(&client_thread, NULL,
+ thread_manage_clients, (void *) NULL);
+ if (ret != 0) {
+ perror("pthread_create clients");
+ goto exit_client;
}
- cleanup();
- exit(EXIT_SUCCESS);
+ /* Create thread to dispatch registration */
+ ret = pthread_create(&dispatch_thread, NULL,
+ thread_dispatch_ust_registration, (void *) NULL);
+ if (ret != 0) {
+ perror("pthread_create dispatch");
+ goto exit_dispatch;
+ }
-error:
+ /* Create thread to manage application registration. */
+ ret = pthread_create(®_apps_thread, NULL,
+ thread_registration_apps, (void *) NULL);
+ if (ret != 0) {
+ perror("pthread_create registration");
+ goto exit_reg_apps;
+ }
+
+ /* Create thread to manage application socket */
+ ret = pthread_create(&apps_thread, NULL,
+ thread_manage_apps, (void *) NULL);
+ if (ret != 0) {
+ perror("pthread_create apps");
+ goto exit_apps;
+ }
+
+ /* Create kernel thread to manage kernel event */
+ ret = pthread_create(&kernel_thread, NULL,
+ thread_manage_kernel, (void *) NULL);
+ if (ret != 0) {
+ perror("pthread_create kernel");
+ goto exit_kernel;
+ }
+
+ ret = pthread_join(kernel_thread, &status);
+ if (ret != 0) {
+ perror("pthread_join");
+ goto error; /* join error, exit without cleanup */
+ }
+
+exit_kernel:
+ ret = pthread_join(apps_thread, &status);
+ if (ret != 0) {
+ perror("pthread_join");
+ goto error; /* join error, exit without cleanup */
+ }
+
+exit_apps:
+ ret = pthread_join(reg_apps_thread, &status);
+ if (ret != 0) {
+ perror("pthread_join");
+ goto error; /* join error, exit without cleanup */
+ }
+
+exit_reg_apps:
+ ret = pthread_join(dispatch_thread, &status);
+ if (ret != 0) {
+ perror("pthread_join");
+ goto error; /* join error, exit without cleanup */
+ }
+
+exit_dispatch:
+ ret = pthread_join(client_thread, &status);
+ if (ret != 0) {
+ perror("pthread_join");
+ goto error; /* join error, exit without cleanup */
+ }
+
+ ret = join_kconsumerd_thread();
+ if (ret != 0) {
+ perror("join_kconsumerd");
+ goto error; /* join error, exit without cleanup */
+ }
+
+exit_client:
+exit:
+ /*
+ * cleanup() is called when no other thread is running.
+ */
cleanup();
+ if (!ret)
+ exit(EXIT_SUCCESS);
+error:
exit(EXIT_FAILURE);
}