LTTng » LTTng-tools

I manually compiled and installed the following packages:

userspace-rcu-0.11.0.tar.gz
lttng-ust-2.11.0.tar.gz
lttng-tools-2.11.0.tar.gz
babeltrace-1.5.7.tar.gz

Version of my environment:

[root@localhost ~]# uname -a
Linux localhost.localdomain 3.10.0-514.44.5.10.h165.x86_64 #1 SMP Tue Feb 26 18:43:36 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

When I start the lttng-sessiond process, I get the following error and the startup fails:

[root@localhost /]# lttng-sessiond --no-kernel --daemonize
PERROR - 21:59:39.270365940 [13146/13146]: remove lock file: No such file or directory (in sessiond_cleanup_lock_file() at main.c:917)

The details are as follows:

[root@localhost /]# lttng-sessiond --no-kernel --daemonize -vvv
DEBUG1 - 21:59:44.528196981 [14732/14732]: [sessiond configuration]
DEBUG1 - 21:59:44.528243054 [14732/14732]:     verbose:                       3
DEBUG1 - 21:59:44.528247187 [14732/14732]:     verbose consumer:              0
DEBUG1 - 21:59:44.528250600 [14732/14732]:     quiet mode:                    False
DEBUG1 - 21:59:44.528253731 [14732/14732]:     agent_tcp_port:                [5345, 5354]
DEBUG1 - 21:59:44.528257251 [14732/14732]:     application socket timeout:    5
DEBUG1 - 21:59:44.528260396 [14732/14732]:     no-kernel:                     True
DEBUG1 - 21:59:44.528263364 [14732/14732]:     background:                    False
DEBUG1 - 21:59:44.528266333 [14732/14732]:     daemonize:                     True
DEBUG1 - 21:59:44.528269469 [14732/14732]:     signal parent on start:        False
DEBUG1 - 21:59:44.528272322 [14732/14732]:     tracing group name:            tracing
DEBUG1 - 21:59:44.528275269 [14732/14732]:     kmod_probe_list:               None
DEBUG1 - 21:59:44.528278401 [14732/14732]:     kmod_extra_probe_list:         None
DEBUG1 - 21:59:44.528281599 [14732/14732]:     rundir:                        /var/run/lttng
DEBUG1 - 21:59:44.528284756 [14732/14732]:     application socket path:       /var/run/lttng/lttng-ust-sock-8
DEBUG1 - 21:59:44.528289975 [14732/14732]:     client socket path:            /var/run/lttng/client-lttng-sessiond
DEBUG1 - 21:59:44.528293229 [14732/14732]:     wait shm path:                 /lttng-ust-wait-8
DEBUG1 - 21:59:44.528296428 [14732/14732]:     health socket path:            /var/run/lttng/sessiond-health
DEBUG1 - 21:59:44.528299639 [14732/14732]:     LTTNG_UST_CLOCK_PLUGIN:        None
DEBUG1 - 21:59:44.528302575 [14732/14732]:     pid file path:                 /var/run/lttng/lttng-sessiond.pid
DEBUG1 - 21:59:44.528305681 [14732/14732]:     lock file path:                /var/run/lttng/lttng-sessiond.lck
DEBUG1 - 21:59:44.528308690 [14732/14732]:     session load path:             None
DEBUG1 - 21:59:44.528311621 [14732/14732]:     agent port file path:          /var/run/lttng/agent.port
DEBUG1 - 21:59:44.528320498 [14732/14732]:     consumerd32 path:              /var/run/lttng/ustconsumerd32
DEBUG1 - 21:59:44.528323678 [14732/14732]:     consumerd32 bin path:          Unknown
DEBUG1 - 21:59:44.528326739 [14732/14732]:     consumerd32 lib dir:           Unknown
DEBUG1 - 21:59:44.528329788 [14732/14732]:     consumerd32 err unix sock path:/var/run/lttng/ustconsumerd32/error
DEBUG1 - 21:59:44.528332689 [14732/14732]:     consumerd32 cmd unix sock path:/var/run/lttng/ustconsumerd32/command
DEBUG1 - 21:59:44.528335552 [14732/14732]:     consumerd64 path:              /var/run/lttng/ustconsumerd64
DEBUG1 - 21:59:44.528338710 [14732/14732]:     consumerd64 bin path:          /usr/lib64/lttng/libexec/lttng-consumerd
DEBUG1 - 21:59:44.528341818 [14732/14732]:     consumerd64 lib dir:           /usr/lib64
DEBUG1 - 21:59:44.528344781 [14732/14732]:     consumerd64 err unix sock path:/var/run/lttng/ustconsumerd64/error
DEBUG1 - 21:59:44.528347947 [14732/14732]:     consumerd64 cmd unix sock path:/var/run/lttng/ustconsumerd64/command
DEBUG1 - 21:59:44.528351043 [14732/14732]:     kconsumerd path:               /var/run/lttng/kconsumerd
DEBUG1 - 21:59:44.528354134 [14732/14732]:     kconsumerd err unix sock path: /var/run/lttng/kconsumerd/error
DEBUG1 - 21:59:44.528357114 [14732/14732]:     kconsumerd cmd unix sock path: /var/run/lttng/kconsumerd/command
DEBUG1 - 21:59:44.528364853 [14732/14732]: Starting lttng-sessiond {aef25127-dc4c-4a92-9c2d-f4c7e719adc8} (in sessiond_uuid_log() at main.c:1288)
DEBUG3 - 21:59:44.528370373 [14732/14732]: Creating LTTng run directory: /var/run/lttng (in create_lttng_rundir() at main.c:1001)
PERROR - 21:59:45.528724959 [14732/14732]: remove lock file: No such file or directory (in sessiond_cleanup_lock_file() at main.c:917)
DEBUG1 - 21:59:45.528753860 [14732/14732]: Cleaning up options (in sessiond_cleanup_options() at main.c:354)
DEBUG1 - 21:59:45.528764827 [14732/14732]: Destroying run_as worker (in run_as_destroy_worker_no_lock() at runas.c:1280)

I tracked the start of lttng-sessiond and found that CMM_LOAD_SHARED failed and the child process exited:

src/common/daemonize.c:lttng_daemonize:102

while (!CMM_LOAD_SHARED(*completion_flag)) {
    int status;
    pid_t ret;

    /*
     * Check if child exists without blocking. If
     * so, we have to stop this parent process and
     * return an error.
     */
    ret = waitpid(pid, &status, WNOHANG);
    if (ret < 0 || (ret != 0 && WIFEXITED(status))) {
        /* The child exited somehow or was not valid. */
        goto error;
    }
    sleep(1);
}

What is CMM_LOAD_SHARED? Is it not supported by my system?