Rename kconsumerd to ltt-kconsumerd
[lttng-tools.git] / ltt-sessiond / main.c
index 56266db3ce429bb6074bf34af85391ce6e7b865e..0effeb1f5ab51a0c91973505c7efd9629dee5a3c 100644 (file)
 #include <grp.h>
 #include <limits.h>
 #include <pthread.h>
+#include <semaphore.h>
 #include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/ipc.h>
+#include <sys/mount.h>
 #include <sys/shm.h>
 #include <sys/socket.h>
 #include <sys/stat.h>
 #include <sys/types.h>
+#include <sys/time.h>
+#include <sys/resource.h>
 #include <unistd.h>
 
 #include <urcu/list.h>         /* URCU list library (-lurcu) */
-#include <ust/ustctl.h>                /* UST control lib (-lust) */
-#include <lttng/liblttngctl.h>
+#include <lttng/lttng.h>
 
 #include "liblttsessiondcomm.h"
 #include "ltt-sessiond.h"
 #include "lttngerr.h"
+#include "kernel-ctl.h"
+#include "ust-ctl.h"
 #include "session.h"
-#include "trace.h"
 #include "traceable-app.h"
+#include "lttng-kconsumerd.h"
+#include "libustctl.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.
+ */
 
 /* Const values */
 const char default_home_dir[] = DEFAULT_HOME_DIR;
-const char default_tracing_group[] = DEFAULT_TRACING_GROUP;
+const char default_tracing_group[] = LTTNG_DEFAULT_TRACING_GROUP;
 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
 
-/* Static functions */
-static int check_existing_daemon(void);
-static int connect_app(pid_t pid);
-static int init_daemon_socket(void);
-static int notify_apps(const char* name);
-static int process_client_msg(int sock, struct lttcomm_session_msg*);
-static int send_unix_sock(int sock, void *buf, size_t len);
-static int set_signal_handler(void);
-static int set_socket_perms(void);
-static int setup_data_buffer(char **buf, size_t size, struct lttcomm_lttng_msg *llm);
-static void cleanup(void);
-static void copy_common_data(struct lttcomm_lttng_msg *llm, struct lttcomm_session_msg *lsm);
-static void sighandler(int sig);
-
-static void *thread_manage_clients(void *data);
-static void *thread_manage_apps(void *data);
-
 /* Variables */
-int opt_verbose;
-int opt_quiet;
+int opt_verbose;    /* 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 opt_daemon;
 static int is_root;                    /* Set to 1 if the daemon is running as root */
-static pid_t ppid;
+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 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 client_socket;
-static int apps_socket;
+/* Sockets and FDs */
+static int client_sock;
+static int apps_sock;
+static int kconsumerd_err_sock;
+static int kconsumerd_cmd_sock;
+static int kernel_tracer_fd;
 
-static struct ltt_session *current_session;
+/* Pthread, Mutexes and Semaphores */
+static pthread_t kconsumerd_thread;
+static pthread_t apps_thread;
+static pthread_t client_thread;
+static sem_t kconsumerd_sem;
+
+static pthread_mutex_t kconsumerd_pid_mutex;   /* Mutex to control kconsumerd pid assignation */
 
 /*
- *     thread_manage_apps
+ *  teardown_kernel_session
  *
- *     This thread manage the application socket communication
+ *  Complete teardown of a kernel session. This free all data structure
+ *  related to a kernel session and update counter.
  */
-static void *thread_manage_apps(void *data)
+static void teardown_kernel_session(struct ltt_session *session)
 {
-       int sock, ret;
+       if (session->kernel_session != NULL) {
+               DBG("Tearing down kernel session");
+               trace_destroy_kernel_session(session->kernel_session);
+               /* Extra precaution */
+               session->kernel_session = NULL;
+               /* Decrement session count */
+               session->kern_session_count--;
+       }
+}
 
-       /* TODO: Something more elegant is needed but fine for now */
-       struct {
-               int reg;        /* 1:register, 0:unregister */
-               pid_t pid;
-               uid_t uid;
-       } reg_msg;
+/*
+ *  cleanup
+ *
+ *  Cleanup the daemon on exit
+ */
+static void cleanup()
+{
+       int ret;
+       char *cmd;
+       struct ltt_session *sess;
 
-       /* Notify all applications to register */
-       notify_apps(default_global_apps_pipe);
+       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);
+       /* </fun> */
 
-       ret = lttcomm_listen_unix_sock(apps_socket);
+       /* Stopping all threads */
+       DBG("Terminating all threads");
+       pthread_cancel(client_thread);
+       pthread_cancel(apps_thread);
+       if (kconsumerd_pid != 0) {
+               pthread_cancel(kconsumerd_thread);
+       }
+
+       DBG("Unlinking all unix socket");
+       unlink(client_unix_sock_path);
+       unlink(apps_unix_sock_path);
+       unlink(kconsumerd_err_unix_sock_path);
+
+       DBG("Removing %s directory", LTTNG_RUNDIR);
+       ret = asprintf(&cmd, "rm -rf " LTTNG_RUNDIR);
        if (ret < 0) {
-               goto error;
+               ERR("asprintf failed. Something is really wrong!");
        }
 
-       while (1) {
-               /* Blocking call, waiting for transmission */
-               sock = lttcomm_accept_unix_sock(apps_socket);
-               if (sock < 0) {
-                       goto error;
-               }
+       /* Remove lttng run directory */
+       ret = system(cmd);
+       if (ret < 0) {
+               ERR("Unable to clean " LTTNG_RUNDIR);
+       }
 
-               /* Basic recv here to handle the very simple data
-                * that the libust send to register (reg_msg).
-                */
-               ret = recv(sock, &reg_msg, sizeof(reg_msg), 0);
-               if (ret < 0) {
-                       perror("recv");
-                       continue;
-               }
+       DBG("Cleaning up all session");
+       /* Cleanup ALL session */
+       cds_list_for_each_entry(sess, &ltt_session_list.head, list) {
+               teardown_kernel_session(sess);
+               // TODO complete session cleanup (including UST)
+       }
 
-               /* 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.
-                                */
-                               goto error;
-                       }
-               } else {
-                       /* Unregistering */
-                       unregister_traceable_app(reg_msg.pid);
-               }
+       DBG("Closing kernel fd");
+       close(kernel_tracer_fd);
+}
+
+/*
+ *  send_unix_sock
+ *
+ *  Send data on a unix socket using the liblttsessiondcomm API.
+ *
+ *  Return lttcomm error code.
+ */
+static int send_unix_sock(int sock, void *buf, size_t len)
+{
+       /* Check valid length */
+       if (len <= 0) {
+               return -1;
        }
 
-error:
+       return lttcomm_send_unix_sock(sock, buf, len);
+}
 
-       return NULL;
+/*
+ *  clean_command_ctx
+ *
+ *  Free memory of a command context structure.
+ */
+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);
+               }
+               if (cmd_ctx->lsm) {
+                       free(cmd_ctx->lsm);
+               }
+               free(cmd_ctx);
+               cmd_ctx = NULL;
+       }
 }
 
 /*
- *     thread_manage_clients
+ *  send_kconsumerd_fds
  *
- *     This thread manage all clients request using the unix
- *     client socket for communication.
+ *  Send all stream fds of the kernel session to the consumer.
  */
-static void *thread_manage_clients(void *data)
+static int send_kconsumerd_fds(int sock, struct ltt_kernel_session *session)
 {
-       int sock, ret;
-       struct lttcomm_session_msg lsm;
+       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;
 
-       ret = lttcomm_listen_unix_sock(client_socket);
+       /* Setup header */
+       lkh.payload_size = (nb_fd + 1) * 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));
        if (ret < 0) {
+               perror("send kconsumerd header");
                goto error;
        }
 
-       /* Notify parent pid that we are ready
-        * to accept command for client side.
-        */
-       if (opt_sig_parent) {
-               kill(ppid, SIGCHLD);
+       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;
        }
 
-       while (1) {
-               /* Blocking call, waiting for transmission */
-               sock = lttcomm_accept_unix_sock(client_socket);
-               if (sock < 0) {
-                       goto error;
-               }
+       cds_list_for_each_entry(chan, &session->channel_list.head, list) {
+               cds_list_for_each_entry(stream, &chan->stream_list.head, list) {
+                       lkm.fd = stream->fd;
+                       lkm.state = stream->state;
+                       lkm.max_sb_size = chan->channel->attr.subbuf_size;
+                       strncpy(lkm.path_name, stream->pathname, PATH_MAX);
 
-               /*
-                * Data is received from the lttng client. The struct
-                * lttcomm_session_msg (lsm) contains the command and data
-                * request of the client.
-                */
-               ret = lttcomm_recv_unix_sock(sock, &lsm, sizeof(lsm));
-               if (ret <= 0) {
-                       continue;
-               }
+                       DBG("Sending fd %d to kconsumerd", lkm.fd);
 
-               /* This function dispatch the work to the LTTng or UST libs
-                * and then sends back the response to the client. This is needed
-                * because there might be more then one lttcomm_lttng_msg to
-                * send out so process_client_msg do both jobs.
-                */
-               ret = process_client_msg(sock, &lsm);
-               if (ret < 0) {
-                       /* Error detected but still accept command */
-                       continue;
+                       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");
+
+       return 0;
+
 error:
-       return NULL;
+       return ret;
 }
 
 /*
- *  send_unix_sock
- *
- *  Send data on a unix socket using the liblttsessiondcomm API.
+ *  create_trace_dir
  *
- *  Return lttcomm error code.
+ *  Create the trace output directory.
  */
-static int send_unix_sock(int sock, void *buf, size_t len)
+static int create_trace_dir(struct ltt_kernel_session *session)
 {
-       /* Check valid length */
-       if (len <= 0) {
-               return -1;
+       int ret;
+       struct ltt_kernel_channel *chan;
+
+       /* 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;
+                       }
+               }
        }
 
-       return lttcomm_send_unix_sock(sock, buf, len);
+       return 0;
+
+error:
+       return ret;
 }
 
 /*
- *     connect_app
+ *     ust_connect_app
  *
  *     Return a socket connected to the libust communication socket
  *     of the application identified by the pid.
@@ -228,20 +308,23 @@ static int send_unix_sock(int sock, void *buf, size_t len)
  *     If the pid is not found in the traceable list,
  *     return -1 to indicate error.
  */
-static int connect_app(pid_t pid)
+static int ust_connect_app(pid_t pid)
 {
        int sock;
        struct ltt_traceable_app *lta;
 
+       DBG("Connect to application pid %d", pid);
+
        lta = find_app_by_pid(pid);
        if (lta == NULL) {
                /* App not found */
+               DBG("Application pid %d not found", pid);
                return -1;
        }
 
        sock = ustctl_connect_pid(lta->pid);
        if (sock < 0) {
-               ERR("Fail connecting to the PID %d\n", pid);
+               ERR("Fail connecting to the PID %d", pid);
        }
 
        return sock;
@@ -261,6 +344,8 @@ static int notify_apps(const char *name)
        int fd;
        int ret = -1;
 
+       DBG("Notify the global application pipe");
+
        /* Try opening the global pipe */
        fd = open(name, O_WRONLY);
        if (fd < 0) {
@@ -278,269 +363,1367 @@ error:
 }
 
 /*
- *  ust_create_trace
+ *  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.
  *
- *  Create an userspace trace using pid.
- *  This trace is then appended to the current session
- *  ust trace list.
+ *  Return total size of the buffer pointed by buf.
  */
-static int ust_create_trace(pid_t pid)
+static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
 {
-       int sock, ret;
-       struct ltt_ust_trace *trace;
+       int ret, buf_size;
 
-       trace = malloc(sizeof(struct ltt_ust_trace));
-       if (trace == NULL) {
+       buf_size = size;
+
+       cmd_ctx->llm = malloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
+       if (cmd_ctx->llm == NULL) {
                perror("malloc");
-               ret = -1;
+               ret = -ENOMEM;
                goto error;
        }
 
-       /* Init */
-       trace->pid = pid;
-       trace->shmid = 0;
+       /* Copy common data */
+       cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
+       cmd_ctx->llm->pid = cmd_ctx->lsm->pid;
 
-       /* Connect to app using ustctl API */
-       sock = connect_app(pid);
+       cmd_ctx->llm->data_size = size;
+       cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
+
+       return buf_size;
+
+error:
+       return ret;
+}
+
+/*
+ *  thread_manage_kconsumerd
+ *
+ *  This thread manage the kconsumerd error sent
+ *  back to the session daemon.
+ */
+static void *thread_manage_kconsumerd(void *data)
+{
+       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) {
-               ret = LTTCOMM_NO_TRACEABLE;
                goto error;
        }
 
-       ret = ustctl_create_trace(sock, "auto");
+       /* Getting status code from kconsumerd */
+       ret = lttcomm_recv_unix_sock(sock, &code, sizeof(enum lttcomm_return_code));
+       if (ret <= 0) {
+               goto error;
+       }
+
+       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;
+       }
+
+       /* 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;
+       }
+
+       ERR("Kconsumerd return code : %s", lttcomm_get_readable_code(-code));
+
+error:
+       kconsumerd_pid = 0;
+       DBG("Kconsumerd thread dying");
+       return NULL;
+}
+
+/*
+ *     thread_manage_apps
+ *
+ *     This thread manage the application socket communication
+ */
+static void *thread_manage_apps(void *data)
+{
+       int sock, ret;
+
+       /* 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("[thread] Manage apps started");
+
+       ret = lttcomm_listen_unix_sock(apps_sock);
        if (ret < 0) {
-               ret = LTTCOMM_CREATE_FAIL;
                goto error;
        }
 
-       /* Check if current session is valid */
-       if (current_session) {
-               cds_list_add(&trace->list, &current_session->ust_traces);
+       /* 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;
+               }
+
+               /* Basic recv here to handle the very simple data
+                * that the libust send to register (reg_msg).
+                */
+               ret = recv(sock, &reg_msg, sizeof(reg_msg), 0);
+               if (ret < 0) {
+                       perror("recv");
+                       continue;
+               }
+
+               /* 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.
+                                */
+                               goto error;
+                       }
+               } else {
+                       /* Unregistering */
+                       unregister_traceable_app(reg_msg.pid);
+               }
        }
 
 error:
-       return ret;
+
+       return NULL;
 }
 
 /*
- *  copy_common_data
+ *  spawn_kconsumerd_thread
  *
- *  Copy common data between lttcomm_lttng_msg and lttcomm_session_msg
+ *  Start the thread_manage_kconsumerd. This must be done after a kconsumerd
+ *  exec or it will fails.
  */
-static void copy_common_data(struct lttcomm_lttng_msg *llm, struct lttcomm_session_msg *lsm)
+static int spawn_kconsumerd_thread(void)
 {
-       llm->cmd_type = lsm->cmd_type;
-       llm->pid = lsm->pid;
+       int ret;
+
+       /* Setup semaphore */
+       sem_init(&kconsumerd_sem, 0, 0);
+
+       ret = pthread_create(&kconsumerd_thread, NULL, thread_manage_kconsumerd, (void *) NULL);
+       if (ret != 0) {
+               perror("pthread_create kconsumerd");
+               goto error;
+       }
+
+       /* Wait for the kconsumerd thread to be ready */
+       sem_wait(&kconsumerd_sem);
+
+       if (kconsumerd_pid == 0) {
+               ERR("Kconsumerd did not start");
+               goto error;
+       }
+
+       return 0;
+
+error:
+       ret = LTTCOMM_KERN_CONSUMER_FAIL;
+       return ret;
+}
+
+/*
+ *  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("Spawning kconsumerd");
+
+       pid = fork();
+       if (pid == 0) {
+               /*
+                * Exec kconsumerd.
+                */
+               execlp("ltt-kconsumerd", "ltt-kconsumerd", "--verbose", 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;
+}
+
+/*
+ *  start_kconsumerd
+ *
+ *  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) {
+               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:
+       pthread_mutex_unlock(&kconsumerd_pid_mutex);
+       return 0;
+
+error:
+       return ret;
+}
+
+/*
+ *  modprobe_kernel_modules
+ */
+static int modprobe_kernel_modules(void)
+{
+       int ret = 0, i = 0;
+       char modprobe[256];
+
+       while (kernel_modules_list[i] != NULL) {
+               ret = snprintf(modprobe, sizeof(modprobe), "/sbin/modprobe %s",
+                               kernel_modules_list[i]);
+               if (ret < 0) {
+                       perror("snprintf modprobe");
+                       goto error;
+               }
+               ret = system(modprobe);
+               if (ret < 0) {
+                       ERR("Unable to load module %s", kernel_modules_list[i]);
+               }
+               DBG("Modprobe successfully %s", kernel_modules_list[i]);
+               i++;
+       }
+
+error:
+       return ret;
+}
+
+/*
+ *  mount_debugfs
+ */
+static int mount_debugfs(char *path)
+{
+       int ret;
+       char *type = "debugfs";
+
+       ret = mkdir_recursive(path, S_IRWXU | S_IRWXG);
+       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;
+}
+
+/*
+ *  init_kernel_tracer
+ *
+ *  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;
+       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(&lttng_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;
+}
+
+/*
+ *  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;
+
+       /* 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;
+               }
+       }
+
+       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;
+                       goto error;
+               }
+
+               session->kconsumer_fds_sent = 1;
+       }
+
+error:
+       return ret;
+}
+
+/*
+ *  init_default_channel
+ *
+ *  Allocate a channel structure and fill it.
+ */
+static struct lttng_channel *init_default_channel(void)
+{
+       struct lttng_channel *chan;
+
+       chan = malloc(sizeof(struct lttng_channel));
+       if (chan == NULL) {
+               perror("init channel malloc");
+               goto error;
+       }
+
+       if (snprintf(chan->name, NAME_MAX, DEFAULT_CHANNEL_NAME) < 0) {
+               perror("snprintf defautl channel name");
+               return NULL;
+       }
+
+       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;
+
+error:
+       return chan;
+}
+
+/*
+ *  create_kernel_session
+ *
+ *  Create a kernel tracer session then create the default channel.
+ */
+static int create_kernel_session(struct ltt_session *session)
+{
+       int ret;
+       struct lttng_channel *chan;
+
+       DBG("Creating kernel session");
+
+       ret = kernel_create_session(session, kernel_tracer_fd);
+       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);
+       if (ret < 0) {
+               ret = LTTCOMM_KERN_CHAN_FAIL;
+               goto error;
+       }
+
+error:
+       return ret;
+}
+
+/*
+ *     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;
+
+       DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
+
+       /* 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;
+                       }
+                       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) {
+
+                       ret = create_kernel_session(cmd_ctx->session);
+                       if (ret < 0) {
+                               ret = LTTCOMM_KERN_SESS_FAIL;
+                               goto error;
+                       }
+
+                       /* Start the kernel consumer daemon */
+                       if (kconsumerd_pid == 0) {
+                               ret = start_kconsumerd();
+                               if (ret < 0) {
+                                       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;
+               }
+
+               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);
+                                       if (ret < 0) {
+                                               continue;
+                                       }
+                               } 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);
+                                               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;
+                               }
+                       } 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);
+                                       if (ret < 0) {
+                                               ret = LTTCOMM_KERN_CONTEXT_FAIL;
+                                               goto error;
+                                       }
+                               }
+                       }
+               }
+
+               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");
+
+               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;
+               }
+
+               ret = LTTCOMM_OK;
+               break;
+       }
+       case LTTNG_KERNEL_DISABLE_CHANNEL:
+       {
+               struct ltt_kernel_channel *chan;
+
+               /* Setup lttng message with no payload */
+               ret = setup_lttng_msg(cmd_ctx, 0);
+               if (ret < 0) {
+                       goto setup_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;
+               } else if (chan->enabled == 1) {
+                       ret = kernel_disable_channel(chan);
+                       if (ret < 0) {
+                               if (ret != EEXIST) {
+                                       ret = LTTCOMM_KERN_CHAN_DISABLE_FAIL;
+                               }
+                               goto error;
+                       }
+               }
+
+               kernel_wait_quiescent(kernel_tracer_fd);
+               ret = LTTCOMM_OK;
+               break;
+       }
+       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;
+               }
+
+               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;
+               }
+
+               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;
+                       }
+               }
+
+               kernel_wait_quiescent(kernel_tracer_fd);
+               ret = LTTCOMM_OK;
+               break;
+       }
+       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;
+               }
+
+               DBG("Disabling all enabled kernel events");
+
+               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;
+               }
+
+               /* 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;
+                       }
+               }
+
+               /* 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;
+
+               /* Setup lttng message with no payload */
+               ret = setup_lttng_msg(cmd_ctx, 0);
+               if (ret < 0) {
+                       goto setup_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;
+                               }
+                               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;
+               }
+
+               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;
+               }
+
+               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);
+               }
+
+               if (ret < 0) {
+                       ret = LTTCOMM_KERN_ENABLE_FAIL;
+                       goto error;
+               }
+
+               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");
+
+               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;
+               }
+
+               /* 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;
+                       }
+               }
+
+               size = kernel_list_events(kernel_tracer_fd, &event_list);
+               if (size < 0) {
+                       ret = LTTCOMM_KERN_LIST_FAIL;
+                       goto error;
+               }
+
+               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 */
+                               }
+                       }
+
+                       /* Move pointer to the next line */
+                       ptr += pos + 1;
+                       free(event);
+               }
+
+               free(event_list);
+
+               /* Quiescent wait after event enable */
+               kernel_wait_quiescent(kernel_tracer_fd);
+               ret = LTTCOMM_OK;
+               break;
+       }
+       case LTTNG_KERNEL_LIST_EVENTS:
+       {
+               char *event_list;
+               ssize_t size = 0;
+
+               DBG("Listing kernel events");
+
+               size = kernel_list_events(kernel_tracer_fd, &event_list);
+               if (size < 0) {
+                       ret = LTTCOMM_KERN_LIST_FAIL;
+                       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;
+               }
+
+               /* Copy event list into message payload */
+               memcpy(cmd_ctx->llm->payload, event_list, size);
+
+               free(event_list);
+
+               ret = LTTCOMM_OK;
+               break;
+       }
+       case LTTNG_START_TRACE:
+       {
+               struct ltt_kernel_channel *chan;
+
+               /* Setup lttng message with no payload */
+               ret = setup_lttng_msg(cmd_ctx, 0);
+               if (ret < 0) {
+                       goto setup_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);
+                               if (ret < 0) {
+                                       ret = LTTCOMM_KERN_META_FAIL;
+                                       goto error;
+                               }
+                       }
+
+                       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;
+                                       }
+                               }
+                       }
+
+                       /* 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;
+                               }
+                       }
+
+                       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;
+                       }
+
+                       ret = start_kernel_trace(cmd_ctx->session->kernel_session);
+                       if (ret < 0) {
+                               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;
+               break;
+       }
+       case LTTNG_STOP_TRACE:
+       {
+               struct ltt_kernel_channel *chan;
+               /* Setup lttng message with no payload */
+               ret = setup_lttng_msg(cmd_ctx, 0);
+               if (ret < 0) {
+                       goto setup_error;
+               }
+
+               /* Kernel tracer */
+               if (cmd_ctx->session->kernel_session != NULL) {
+                       DBG("Stop kernel tracing");
+
+                       ret = kernel_metadata_flush_buffer(cmd_ctx->session->kernel_session->metadata_stream_fd);
+                       if (ret < 0) {
+                               ERR("Kernel metadata flush failed");
+                       }
+
+                       cds_list_for_each_entry(chan, &cmd_ctx->session->kernel_session->channel_list.head, list) {
+                               ret = kernel_flush_buffer(chan);
+                               if (ret < 0) {
+                                       ERR("Kernel flush buffer 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;
+                       }
+
+                       /* Quiescent wait after stopping trace */
+                       kernel_wait_quiescent(kernel_tracer_fd);
+               }
+
+               /* TODO : User-space tracer */
+
+               ret = LTTCOMM_OK;
+               break;
+       }
+       case LTTNG_CREATE_SESSION:
+       {
+               /* 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;
+               break;
+       }
+       case LTTNG_DESTROY_SESSION:
+       {
+               /* 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;
+               }
+
+               ret = LTTCOMM_OK;
+               break;
+       }
+       /*
+       case LTTNG_LIST_TRACES:
+       {
+               unsigned int trace_count;
+
+               trace_count = get_trace_count_per_session(cmd_ctx->session);
+               if (trace_count == 0) {
+                       ret = LTTCOMM_NO_TRACE;
+                       goto error;
+               }
+
+               ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_trace) * trace_count);
+               if (ret < 0) {
+                       goto setup_error;
+               }
+
+               get_traces_per_session(cmd_ctx->session,
+                               (struct lttng_trace *)(cmd_ctx->llm->payload));
+
+               ret = LTTCOMM_OK;
+               break;
+       }
+       */
+       /*
+       case UST_CREATE_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;
+               }
+               break;
+       }
+       */
+       case LTTNG_LIST_TRACEABLE_APPS:
+       {
+               unsigned int app_count;
+
+               app_count = get_app_count();
+               DBG("Traceable application count : %d", app_count);
+               if (app_count == 0) {
+                       ret = LTTCOMM_NO_APPS;
+                       goto error;
+               }
+
+               ret = setup_lttng_msg(cmd_ctx, sizeof(pid_t) * app_count);
+               if (ret < 0) {
+                       goto setup_error;
+               }
+
+               get_app_list_pids((pid_t *)(cmd_ctx->llm->payload));
+
+               ret = LTTCOMM_OK;
+               break;
+       }
+       /*
+       case UST_START_TRACE:
+       {
+               ret = setup_lttng_msg(cmd_ctx, 0);
+               if (ret < 0) {
+                       goto setup_error;
+               }
+
+               ret = ust_start_trace(cmd_ctx);
+               if (ret < 0) {
+                       goto setup_error;
+               }
+               break;
+       }
+       case UST_STOP_TRACE:
+       {
+               ret = setup_lttng_msg(cmd_ctx, 0);
+               if (ret < 0) {
+                       goto setup_error;
+               }
 
-       /* Manage uuid */
-       if (!uuid_is_null(lsm->session_id)) {
-               uuid_copy(llm->session_id, lsm->session_id);
+               ret = ust_stop_trace(cmd_ctx);
+               if (ret < 0) {
+                       goto setup_error;
+               }
+               break;
        }
+       */
+       case LTTNG_LIST_SESSIONS:
+       {
+               unsigned int session_count;
 
-       strncpy(llm->trace_name, lsm->trace_name, strlen(llm->trace_name));
-       llm->trace_name[strlen(llm->trace_name) - 1] = '\0';
-}
+               session_count = get_session_count();
+               if (session_count == 0) {
+                       ret = LTTCOMM_NO_SESSION;
+                       goto error;
+               }
 
-/*
- *  setup_data_buffer
- *
- *  Setup the outgoing data buffer for the response
- *  data allocating the right amount of memory.
- *
- *  Return total size of the buffer pointed by buf.
- */
-static int setup_data_buffer(char **buf, size_t s_data, struct lttcomm_lttng_msg *llm)
-{
-       int ret = 0;
-       size_t buf_size;
+               ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * session_count);
+               if (ret < 0) {
+                       goto setup_error;
+               }
 
-       buf_size = sizeof(struct lttcomm_lttng_msg) + s_data;
-       *buf = malloc(buf_size);
-       if (*buf == NULL) {
-               perror("malloc");
-               ret = -1;
-               goto error;
+               get_lttng_session((struct lttng_session *)(cmd_ctx->llm->payload));
+
+               ret = LTTCOMM_OK;
+               break;
        }
+       default:
+               /* Undefined command */
+               ret = setup_lttng_msg(cmd_ctx, 0);
+               if (ret < 0) {
+                       goto setup_error;
+               }
 
-       /* Setup lttcomm_lttng_msg data and copy
-        * it to the newly allocated buffer.
-        */
-       llm->size_payload = s_data;
-       memcpy(*buf, llm, sizeof(struct lttcomm_lttng_msg));
+               ret = LTTCOMM_UND;
+               break;
+       }
 
-       return buf_size;
+       /* Set return code */
+       cmd_ctx->llm->ret_code = ret;
+
+       return ret;
 
 error:
+       if (cmd_ctx->llm == NULL) {
+               DBG("Missing llm structure. Allocating one.");
+               if (setup_lttng_msg(cmd_ctx, 0) < 0) {
+                       goto setup_error;
+               }
+       }
+       /* Notify client of error */
+       cmd_ctx->llm->ret_code = ret;
+
+setup_error:
        return ret;
 }
 
 /*
- *     process_client_msg
- *
- *     This takes the lttcomm_session_msg struct and process the command requested
- *     by the client. It then creates response(s) and send it back to the
- *     given socket (sock).
+ *     thread_manage_clients
  *
- *     Return any error encountered or 0 for success.
+ *     This thread manage all clients request using the unix
+ *     client socket for communication.
  */
-static int process_client_msg(int sock, struct lttcomm_session_msg *lsm)
+static void *thread_manage_clients(void *data)
 {
-       int ret;
-       int buf_size;
-       size_t header_size;
-       char *send_buf = NULL;
-       struct lttcomm_lttng_msg llm;
+       int sock, ret;
+       struct command_ctx *cmd_ctx;
 
-       /* Copy common data to identify the response
-        * on the lttng client side.
-        */
-       copy_common_data(&llm, lsm);
+       DBG("[thread] Manage client started");
 
-       /* Check command that needs a session */
-       if (lsm->cmd_type != LTTNG_CREATE_SESSION &&
-               lsm->cmd_type != LTTNG_LIST_SESSIONS &&
-               lsm->cmd_type != UST_LIST_APPS)
-       {
-               current_session = find_session_by_uuid(lsm->session_id);
-               if (current_session == NULL) {
-                       ret = LTTCOMM_SELECT_SESS;
-                       goto end;
-               }
+       ret = lttcomm_listen_unix_sock(client_sock);
+       if (ret < 0) {
+               goto error;
        }
 
-       /* Default return code.
-        * In our world, everything is OK... right? ;)
+       /* Notify parent pid that we are ready
+        * to accept command for client side.
         */
-       llm.ret_code = LTTCOMM_OK;
-
-       header_size = sizeof(struct lttcomm_lttng_msg);
-
-       /* Process by command type */
-       switch (lsm->cmd_type) {
-               case LTTNG_CREATE_SESSION:
-               {
-                       ret = create_session(lsm->session_name, &llm.session_id);
-                       if (ret < 0) {
-                               if (ret == -1) {
-                                       ret = LTTCOMM_EXIST_SESS;
-                               } else {
-                                       ret = LTTCOMM_FATAL;
-                               }
-                               goto end;
-                       }
-
-                       buf_size = setup_data_buffer(&send_buf, 0, &llm);
-                       if (buf_size < 0) {
-                               ret = LTTCOMM_FATAL;
-                               goto end;
-                       }
-
-                       break;
-               }
-               case LTTNG_DESTROY_SESSION:
-               {
-                       ret = destroy_session(&lsm->session_id);
-                       if (ret < 0) {
-                               ret = LTTCOMM_NO_SESS;
-                       } else {
-                               ret = LTTCOMM_OK;
-                       }
-
-                       /* No auxiliary data so only send the llm struct. */
-                       goto end;
-               }
-               case UST_CREATE_TRACE:
-               {
-                       ret = ust_create_trace(lsm->pid);
-                       if (ret < 0) {
-                               ret = LTTCOMM_CREATE_FAIL;
-                               goto end;
-                       }
+       if (opt_sig_parent) {
+               kill(ppid, SIGCHLD);
+       }
 
-                       /* No auxiliary data so only send the llm struct. */
-                       goto end;
+       while (1) {
+               /* Blocking call, waiting for transmission */
+               DBG("Accepting client command ...");
+               sock = lttcomm_accept_unix_sock(client_sock);
+               if (sock < 0) {
+                       goto error;
                }
-               case UST_LIST_APPS:
-               {
-                       unsigned int app_count = get_app_count();
-                       /* Stop right now if no apps */
-                       if (app_count == 0) {
-                               ret = LTTCOMM_NO_APPS;
-                               goto end;
-                       }
 
-                       /* Setup data buffer and details for transmission */
-                       buf_size = setup_data_buffer(&send_buf,
-                                       sizeof(pid_t) * app_count, &llm);
-                       if (buf_size < 0) {
-                               ret = LTTCOMM_FATAL;
-                               goto end;
-                       }
+               /* Allocate context command to process the client request */
+               cmd_ctx = malloc(sizeof(struct command_ctx));
 
-                       get_app_list_pids((pid_t *)(send_buf + header_size));
+               /* Allocate data buffer for reception */
+               cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg));
+               cmd_ctx->llm = NULL;
+               cmd_ctx->session = NULL;
 
-                       break;
+               /*
+                * Data is received from the lttng client. The struct
+                * lttcomm_session_msg (lsm) contains the command and data request of
+                * the client.
+                */
+               DBG("Receiving data from client ...");
+               ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm, sizeof(struct lttcomm_session_msg));
+               if (ret <= 0) {
+                       continue;
                }
-               case LTTNG_LIST_SESSIONS:
-               {
-                       unsigned int session_count = get_session_count();
-                       /* Stop right now if no session */
-                       if (session_count == 0) {
-                               ret = LTTCOMM_NO_SESS;
-                               goto end;
-                       }
 
-                       /* Setup data buffer and details for transmission */
-                       buf_size = setup_data_buffer(&send_buf,
-                                       (sizeof(struct lttng_session) * session_count), &llm);
-                       if (buf_size < 0) {
-                               ret = LTTCOMM_FATAL;
-                               goto end;
-                       }
+               // TODO: Validate cmd_ctx including sanity check for security purpose.
 
-                       get_lttng_session((struct lttng_session *)(send_buf + header_size));
-
-                       break;
+               /*
+                * This function dispatch the work to the kernel or userspace tracer
+                * libs and fill the lttcomm_lttng_msg data structure of all the needed
+                * informations for the client. The command context struct contains
+                * everything this function may needs.
+                */
+               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);
+                       continue;
                }
-               default:
-               {
-                       /* Undefined command */
-                       ret = LTTCOMM_UND;
-                       goto end;
+
+               DBG("Sending response (size: %d, retcode: %d)",
+                               cmd_ctx->lttng_msg_size, 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");
                }
-       }
 
-       ret = send_unix_sock(sock, send_buf, buf_size);
+               clean_command_ctx(cmd_ctx);
 
-       if (send_buf != NULL) {
-               free(send_buf);
+               /* End of transmission */
+               close(sock);
        }
 
-       return ret;
-
-end:
-       /* Notify client of error */
-       llm.ret_code = ret;
-       llm.size_payload = 0;
-       send_unix_sock(sock, (void*) &llm, sizeof(llm));
-
-       return ret;
+error:
+       return NULL;
 }
 
+
 /*
  * usage function on stderr
  */
 static void usage(void)
 {
        fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
-       fprintf(stderr, "  -h, --help                Display this usage.\n");
-       fprintf(stderr, "  -c, --client-sock PATH    Specify path for the client unix socket\n");
-       fprintf(stderr, "  -a, --apps-sock PATH      Specify path for apps unix socket.\n");
-       fprintf(stderr, "  -d, --daemonize           Start as a daemon.\n");
-       fprintf(stderr, "  -g, --group NAME          Specify the tracing group name. (default: tracing)\n");
-       fprintf(stderr, "  -V, --version             Show version number.\n");
-       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, "  -h, --help                         Display this usage.\n");
+       fprintf(stderr, "  -c, --client-sock PATH             Specify path for the client unix socket\n");
+       fprintf(stderr, "  -a, --apps-sock PATH               Specify path for apps unix socket\n");
+       fprintf(stderr, "      --kconsumerd-err-sock PATH     Specify path for the kernel consumer error socket\n");
+       fprintf(stderr, "      --kconsumerd-cmd-sock PATH     Specify path for the kernel consumer command socket\n");
+       fprintf(stderr, "  -d, --daemonize                    Start as a daemon.\n");
+       fprintf(stderr, "  -g, --group NAME                   Specify the tracing group name. (default: tracing)\n");
+       fprintf(stderr, "  -V, --version                      Show version number.\n");
+       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");
 }
 
 /*
@@ -553,18 +1736,21 @@ static int parse_args(int argc, char **argv)
        static struct option long_options[] = {
                { "client-sock", 1, 0, 'c' },
                { "apps-sock", 1, 0, 'a' },
+               { "kconsumerd-cmd-sock", 1, 0, 0 },
+               { "kconsumerd-err-sock", 1, 0, 0 },
                { "daemonize", 0, 0, 'd' },
                { "sig-parent", 0, 0, 'S' },
                { "help", 0, 0, 'h' },
                { "group", 1, 0, 'g' },
                { "version", 0, 0, 'V' },
                { "quiet", 0, 0, 'q' },
+               { "verbose", 0, 0, 'v' },
                { NULL, 0, 0, 0 }
        };
 
        while (1) {
                int option_index = 0;
-               c = getopt_long(argc, argv, "dhqVS" "a:c:g:s:", long_options, &option_index);
+               c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:E:C:", long_options, &option_index);
                if (c == -1) {
                        break;
                }
@@ -597,9 +1783,18 @@ static int parse_args(int argc, char **argv)
                case 'S':
                        opt_sig_parent = 1;
                        break;
+               case 'E':
+                       snprintf(kconsumerd_err_unix_sock_path, PATH_MAX, "%s", optarg);
+                       break;
+               case 'C':
+                       snprintf(kconsumerd_cmd_unix_sock_path, PATH_MAX, "%s", optarg);
+                       break;
                case 'q':
                        opt_quiet = 1;
                        break;
+               case 'v':
+                       opt_verbose = 1;
+                       break;
                default:
                        /* Unknown option or other error.
                         * Error is printed by getopt, just return */
@@ -614,8 +1809,8 @@ static int parse_args(int argc, char **argv)
  *     init_daemon_socket
  *
  *     Creates the two needed socket by the daemon.
- *         apps_socket - The communication socket for all UST apps.
- *         client_socket - The communication of the cli tool (lttng).
+ *         apps_sock - The communication socket for all UST apps.
+ *         client_sock - The communication of the cli tool (lttng).
  */
 static int init_daemon_socket()
 {
@@ -625,8 +1820,9 @@ static int init_daemon_socket()
        old_umask = umask(0);
 
        /* Create client tool unix socket */
-       client_socket = lttcomm_create_unix_sock(client_unix_sock_path);
-       if (client_socket < 0) {
+       client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
+       if (client_sock < 0) {
+               ERR("Create unix sock failed: %s", client_unix_sock_path);
                ret = -1;
                goto end;
        }
@@ -634,20 +1830,23 @@ static int init_daemon_socket()
        /* File permission MUST be 660 */
        ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
        if (ret < 0) {
+               ERR("Set file permissions failed: %s", client_unix_sock_path);
                perror("chmod");
                goto end;
        }
 
        /* Create the application unix socket */
-       apps_socket = lttcomm_create_unix_sock(apps_unix_sock_path);
-       if (apps_socket < 0) {
+       apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
+       if (apps_sock < 0) {
+               ERR("Create unix sock failed: %s", apps_unix_sock_path);
                ret = -1;
                goto end;
        }
 
-       /* File permission MUST be 660 */
+       /* File permission MUST be 666 */
        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");
                goto end;
        }
@@ -676,30 +1875,14 @@ static int check_existing_daemon()
 }
 
 /*
- *  get_home_dir
+ *  set_permissions
  *
- *  Return pointer to home directory path using
- *  the env variable HOME.
- *
- *  Default : /tmp
- */
-static const char *get_home_dir(void)
-{
-       const char *home_path;
-
-       if ((home_path = (const char *) getenv("HOME")) == NULL) {
-               home_path = default_home_dir;
-       }
-
-       return home_path;
-}
-
-/*
- *  set_socket_perms
+ *  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).
  */
-static int set_socket_perms(void)
+static int set_permissions(void)
 {
        int ret;
        struct group *grp;
@@ -710,20 +1893,140 @@ static int set_socket_perms(void)
                (grp = getgrnam(default_tracing_group));
 
        if (grp == NULL) {
-               ERR("Missing tracing group. Aborting execution.\n");
-               ret = -1;
+               if (is_root) {
+                       WARN("No tracing group detected");
+                       ret = 0;
+               } else {
+                       ERR("Missing tracing group. Aborting execution.");
+                       ret = -1;
+               }
                goto end;
        }
 
+       /* Set lttng run dir */
+       ret = chown(LTTNG_RUNDIR, 0, grp->gr_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);
        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);
+       if (ret < 0) {
+               ERR("Unable to set group on %s", kconsumerd_err_unix_sock_path);
                perror("chown");
        }
 
+       DBG("All permissions are set");
+
 end:
        return ret;
 }
 
+/*
+ *  create_lttng_rundir
+ *
+ *  Create the lttng run directory needed for all
+ *  global sockets and pipe.
+ */
+static int create_lttng_rundir(void)
+{
+       int ret;
+
+       ret = mkdir(LTTNG_RUNDIR, S_IRWXU | S_IRWXG );
+       if (ret < 0) {
+               if (errno != EEXIST) {
+                       ERR("Unable to create " LTTNG_RUNDIR);
+                       goto error;
+               } else {
+                       ret = 0;
+               }
+       }
+
+error:
+       return ret;
+}
+
+/*
+ *  set_kconsumerd_sockets
+ *
+ *  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);
+       }
+
+       if (strlen(kconsumerd_cmd_unix_sock_path) == 0) {
+               snprintf(kconsumerd_cmd_unix_sock_path, PATH_MAX, KCONSUMERD_CMD_SOCK_PATH);
+       }
+
+       ret = mkdir(KCONSUMERD_PATH, S_IRWXU | S_IRWXG);
+       if (ret < 0) {
+               if (errno != EEXIST) {
+                       ERR("Failed to create " KCONSUMERD_PATH);
+                       goto error;
+               }
+               ret = 0;
+       }
+
+       /* Create the kconsumerd error unix socket */
+       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;
+               goto error;
+       }
+
+       /* File permission MUST be 660 */
+       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");
+               goto error;
+       }
+
+error:
+       return ret;
+}
+
+/*
+ *  sighandler
+ *
+ *  Signal handler for the daemon
+ */
+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;
+       }
+
+       exit(EXIT_SUCCESS);
+}
+
 /*
  *  set_signal_handler
  *
@@ -759,44 +2062,29 @@ static int set_signal_handler(void)
                return ret;
        }
 
-       return ret;
-}
-
-/**
- *  sighandler
- *
- *  Signal handler for the daemon
- */
-static void sighandler(int sig)
-{
-       switch (sig) {
-               case SIGPIPE:
-                       return;
-               case SIGINT:
-               case SIGTERM:
-                       cleanup();
-                       break;
-               default:
-                       break;
-       }
+       DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
 
-       exit(EXIT_SUCCESS);
+       return ret;
 }
 
 /*
- *  cleanup
+ *  set_ulimit
  *
- *  Cleanup the daemon on exit
+ *  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 cleanup()
+static void set_ulimit(void)
 {
-       /* <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);
-       /* </fun> */
+       int ret;
+       struct rlimit lim;
 
-       unlink(client_unix_sock_path);
-       unlink(apps_unix_sock_path);
+       lim.rlim_cur = 65535;
+       lim.rlim_max = 65535;
+
+       ret = setrlimit(RLIMIT_NOFILE, &lim);
+       if (ret < 0) {
+               perror("failed to set open files limit");
+       }
 }
 
 /*
@@ -804,10 +2092,9 @@ static void cleanup()
  */
 int main(int argc, char **argv)
 {
-       int i;
        int ret = 0;
        void *status;
-       pthread_t threads[2];
+       const char *home_path;
 
        /* Parse arguments */
        progname = argv[0];
@@ -827,52 +2114,77 @@ int main(int argc, char **argv)
        /* Check if daemon is UID = 0 */
        is_root = !getuid();
 
-       /* Set all sockets path */
        if (is_root) {
+               ret = create_lttng_rundir();
+               if (ret < 0) {
+                       goto error;
+               }
+
                if (strlen(apps_unix_sock_path) == 0) {
-                       (snprintf(apps_unix_sock_path, PATH_MAX,
-                                       DEFAULT_GLOBAL_APPS_UNIX_SOCK));
+                       snprintf(apps_unix_sock_path, PATH_MAX,
+                                       DEFAULT_GLOBAL_APPS_UNIX_SOCK);
                }
 
                if (strlen(client_unix_sock_path) == 0) {
-                       (snprintf(client_unix_sock_path, PATH_MAX,
-                                       DEFAULT_GLOBAL_CLIENT_UNIX_SOCK));
+                       snprintf(client_unix_sock_path, PATH_MAX,
+                                       DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
+               }
+
+               ret = set_kconsumerd_sockets();
+               if (ret < 0) {
+                       goto error;
                }
+
+               /* 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.");
+                       goto error;
+               }
+
                if (strlen(apps_unix_sock_path) == 0) {
-                       (snprintf(apps_unix_sock_path, PATH_MAX,
-                                       DEFAULT_HOME_APPS_UNIX_SOCK, get_home_dir()));
+                       snprintf(apps_unix_sock_path, PATH_MAX,
+                                       DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
                }
 
                /* Set the cli tool unix socket path */
                if (strlen(client_unix_sock_path) == 0) {
-                       (snprintf(client_unix_sock_path, PATH_MAX,
-                                       DEFAULT_HOME_CLIENT_UNIX_SOCK, get_home_dir()));
+                       snprintf(client_unix_sock_path, PATH_MAX,
+                                       DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
                }
        }
 
+       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
         */
        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 working.
+                * cleanup() because a daemon is already running.
                 */
-               return EXIT_FAILURE;
+               exit(EXIT_FAILURE);
        }
 
        if (set_signal_handler() < 0) {
                goto error;
        }
 
-       /* Setup the two needed unix socket */
+       /* Setup the needed unix socket */
        if (init_daemon_socket() < 0) {
                goto error;
        }
 
        /* Set credentials to socket */
-       if (is_root && (set_socket_perms() < 0)) {
+       if (is_root && (set_permissions() < 0)) {
                goto error;
        }
 
@@ -883,33 +2195,30 @@ int main(int argc, char **argv)
 
        while (1) {
                /* Create thread to manage the client socket */
-               ret = pthread_create(&threads[0], NULL, thread_manage_clients, (void *) NULL);
+               ret = pthread_create(&client_thread, NULL, thread_manage_clients, (void *) NULL);
                if (ret != 0) {
                        perror("pthread_create");
                        goto error;
                }
 
                /* Create thread to manage application socket */
-               ret = pthread_create(&threads[1], NULL, thread_manage_apps, (void *) NULL);
+               ret = pthread_create(&apps_thread, NULL, thread_manage_apps, (void *) NULL);
                if (ret != 0) {
                        perror("pthread_create");
                        goto error;
                }
 
-               for (i = 0; i < 2; i++) {
-                       ret = pthread_join(threads[i], &status);
-                       if (ret != 0) {
-                               perror("pthread_join");
-                               goto error;
-                       }
+               ret = pthread_join(client_thread, &status);
+               if (ret != 0) {
+                       perror("pthread_join");
+                       goto error;
                }
        }
 
        cleanup();
-       return 0;
+       exit(EXIT_SUCCESS);
 
 error:
        cleanup();
-
-       return EXIT_FAILURE;
+       exit(EXIT_FAILURE);
 }
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