X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fcmd.c;h=8a17dd62a0ce39fc3e980fb9fd64bb78fe125207;hb=d0c66a34ba4c0e20b3af0f81761099b6b6a9adc1;hp=20b0720604e4f2379ab7053e1ac769dda1976405;hpb=f17600c2f71dd3172b2f10f86f2834ceb90dc420;p=lttng-tools.git diff --git a/src/bin/lttng-sessiond/cmd.c b/src/bin/lttng-sessiond/cmd.c index 20b072060..8a17dd62a 100644 --- a/src/bin/lttng-sessiond/cmd.c +++ b/src/bin/lttng-sessiond/cmd.c @@ -916,7 +916,7 @@ int cmd_enable_channel(struct ltt_session *session, * Don't try to enable a channel if the session has been started at * some point in time before. The tracer does not allow it. */ - if (session->started) { + if (session->has_been_started) { ret = LTTNG_ERR_TRACE_ALREADY_STARTED; goto error; } @@ -931,6 +931,16 @@ int cmd_enable_channel(struct ltt_session *session, attr->attr.switch_timer_interval = 0; } + /* + * The ringbuffer (both in user space and kernel) behave badly in overwrite + * mode and with less than 2 subbuf so block it right away and send back an + * invalid attribute error. + */ + if (attr->attr.overwrite && attr->attr.num_subbuf < 2) { + ret = LTTNG_ERR_INVALID; + goto error; + } + switch (domain->type) { case LTTNG_DOMAIN_KERNEL: { @@ -939,15 +949,6 @@ int cmd_enable_channel(struct ltt_session *session, kchan = trace_kernel_get_channel_by_name(attr->name, session->kernel_session); if (kchan == NULL) { - /* - * Don't try to create a channel if the session - * has been started at some point in time - * before. The tracer does not allow it. - */ - if (session->started) { - ret = LTTNG_ERR_TRACE_ALREADY_STARTED; - goto error; - } ret = channel_kernel_create(session->kernel_session, attr, wpipe); if (attr->name[0] != '\0') { session->kernel_session->has_non_default_channel = 1; @@ -971,15 +972,6 @@ int cmd_enable_channel(struct ltt_session *session, uchan = trace_ust_find_channel_by_name(chan_ht, attr->name); if (uchan == NULL) { - /* - * Don't try to create a channel if the session - * has been started at some point in time - * before. The tracer does not allow it. - */ - if (session->started) { - ret = LTTNG_ERR_TRACE_ALREADY_STARTED; - goto error; - } ret = channel_ust_create(usess, attr, domain->buf_type); if (attr->name[0] != '\0') { usess->has_non_default_channel = 1; @@ -1461,7 +1453,7 @@ int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain, tmp_dom.type = LTTNG_DOMAIN_UST; ret = cmd_enable_event(session, &tmp_dom, DEFAULT_JUL_CHANNEL_NAME, - &uevent, NULL, NULL, wpipe); + &uevent, filter, NULL, wpipe); if (ret != LTTNG_OK && ret != LTTNG_ERR_UST_EVENT_ENABLED) { goto error; } @@ -1802,8 +1794,8 @@ int cmd_start_trace(struct ltt_session *session) ksession = session->kernel_session; usess = session->ust_session; - if (session->enabled) { - /* Already started. */ + /* Is the session already started? */ + if (session->active) { ret = LTTNG_ERR_TRACE_ALREADY_STARTED; goto error; } @@ -1823,8 +1815,6 @@ int cmd_start_trace(struct ltt_session *session) goto error; } - session->enabled = 1; - /* Kernel tracing */ if (ksession != NULL) { ret = start_kernel_session(ksession, kernel_tracer_fd); @@ -1844,7 +1834,9 @@ int cmd_start_trace(struct ltt_session *session) } } - session->started = 1; + /* Flag this after a successful start. */ + session->has_been_started = 1; + session->active = 1; ret = LTTNG_OK; @@ -1868,13 +1860,12 @@ int cmd_stop_trace(struct ltt_session *session) ksession = session->kernel_session; usess = session->ust_session; - if (!session->enabled) { + /* Session is not active. Skip everythong and inform the client. */ + if (!session->active) { ret = LTTNG_ERR_TRACE_ALREADY_STOPPED; goto error; } - session->enabled = 0; - /* Kernel tracer */ if (ksession && ksession->started) { DBG("Stop kernel tracing"); @@ -1916,6 +1907,8 @@ int cmd_stop_trace(struct ltt_session *session) } } + /* Flag inactive after a successful stop. */ + session->active = 0; ret = LTTNG_OK; error: @@ -1937,8 +1930,8 @@ int cmd_set_consumer_uri(int domain, struct ltt_session *session, assert(uris); assert(nb_uri > 0); - /* Can't enable consumer after session started. */ - if (session->enabled) { + /* Can't set consumer URI if the session is active. */ + if (session->active) { ret = LTTNG_ERR_TRACE_ALREADY_STARTED; goto error; } @@ -1978,6 +1971,17 @@ int cmd_set_consumer_uri(int domain, struct ltt_session *session, } } + /* + * Make sure to set the session in output mode after we set URI since a + * session can be created without URL (thus flagged in no output mode). + */ + session->output_traces = 1; + if (ksess) { + ksess->output_traces = 1; + } else if (usess) { + usess->output_traces = 1; + } + /* All good! */ ret = LTTNG_OK; @@ -2505,7 +2509,7 @@ void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid, strncpy(sessions[i].name, session->name, NAME_MAX); sessions[i].name[NAME_MAX - 1] = '\0'; - sessions[i].enabled = session->enabled; + sessions[i].enabled = session->active; sessions[i].snapshot_mode = session->snapshot_mode; sessions[i].live_timer_interval = session->live_timer; i++; @@ -2525,9 +2529,24 @@ int cmd_data_pending(struct ltt_session *session) assert(session); /* Session MUST be stopped to ask for data availability. */ - if (session->enabled) { + if (session->active) { ret = LTTNG_ERR_SESSION_STARTED; goto error; + } else { + /* + * If stopped, just make sure we've started before else the above call + * will always send that there is data pending. + * + * The consumer assumes that when the data pending command is received, + * the trace has been started before or else no output data is written + * by the streams which is a condition for data pending. So, this is + * *VERY* important that we don't ask the consumer before a start + * trace. + */ + if (!session->has_been_started) { + ret = 0; + goto error; + } } if (ksess && ksess->consumer) { @@ -2958,7 +2977,7 @@ int cmd_snapshot_record(struct ltt_session *session, } /* The session needs to be started at least once. */ - if (!session->started) { + if (!session->has_been_started) { ret = LTTNG_ERR_START_SESSION_ONCE; goto error; }