Fix: set session in output mode if URL are set afterwards

[lttng-tools.git] / src / bin / lttng-sessiond / cmd.c

diff --git a/src/bin/lttng-sessiond/cmd.c b/src/bin/lttng-sessiond/cmd.c
index dcb5da5f44864a84af1004669c760b6a77e5f06a..c1f5a4e70b7ce83545ce0858db2f781b563fdc26 100644 (file)
--- a/src/bin/lttng-sessiond/cmd.c
+++ b/src/bin/lttng-sessiond/cmd.c
@@ -462,9 +462,6 @@ static int init_kernel_tracing(struct ltt_kernel_session *session)
        if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
                cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
                                socket, node.node) {
-                       /* Code flow error */
-                       assert(socket->fd);
-
                        pthread_mutex_lock(socket->lock);
                        ret = kernel_consumer_send_session(socket, session);
                        pthread_mutex_unlock(socket->lock);
@@ -674,9 +671,6 @@ int cmd_setup_relayd(struct ltt_session *session)
                /* For each consumer socket, send relayd sockets */
                cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
                                socket, node.node) {
-                       /* Code flow error */
-                       assert(socket->fd);
-
                        pthread_mutex_lock(socket->lock);
                        ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
                                        usess->consumer, socket);
@@ -693,9 +687,6 @@ int cmd_setup_relayd(struct ltt_session *session)
                        && ksess->consumer->enabled) {
                cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
                                socket, node.node) {
-                       /* Code flow error */
-                       assert(socket->fd);
-
                        pthread_mutex_lock(socket->lock);
                        ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
                                        ksess->consumer, socket);
@@ -859,6 +850,16 @@ int cmd_enable_channel(struct ltt_session *session,
 
        rcu_read_lock();
 
+       /*
+        * 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:
        {
@@ -1592,6 +1593,7 @@ error:
 int cmd_start_trace(struct ltt_session *session)
 {
        int ret;
+       unsigned long nb_chan = 0;
        struct ltt_kernel_session *ksession;
        struct ltt_ust_session *usess;
 
@@ -1607,6 +1609,21 @@ int cmd_start_trace(struct ltt_session *session)
                goto error;
        }
 
+       /*
+        * Starting a session without channel is useless since after that it's not
+        * possible to enable channel thus inform the client.
+        */
+       if (usess && usess->domain_global.channels) {
+               nb_chan += lttng_ht_get_count(usess->domain_global.channels);
+       }
+       if (ksession) {
+               nb_chan += ksession->channel_count;
+       }
+       if (!nb_chan) {
+               ret = LTTNG_ERR_NO_CHANNEL;
+               goto error;
+       }
+
        session->enabled = 1;
 
        /* Kernel tracing */
@@ -1762,6 +1779,17 @@ 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;
 
@@ -1965,7 +1993,14 @@ int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
        {
                struct lttng_kernel_calibrate kcalibrate;
 
-               kcalibrate.type = calibrate->type;
+               switch (calibrate->type) {
+               case LTTNG_CALIBRATE_FUNCTION:
+               default:
+                       /* Default and only possible calibrate option. */
+                       kcalibrate.type = LTTNG_KERNEL_CALIBRATE_KRETPROBE;
+                       break;
+               }
+
                ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
                if (ret < 0) {
                        ret = LTTNG_ERR_KERN_ENABLE_FAIL;
@@ -1977,7 +2012,14 @@ int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
        {
                struct lttng_ust_calibrate ucalibrate;
 
-               ucalibrate.type = calibrate->type;
+               switch (calibrate->type) {
+               case LTTNG_CALIBRATE_FUNCTION:
+               default:
+                       /* Default and only possible calibrate option. */
+                       ucalibrate.type = LTTNG_UST_CALIBRATE_TRACEPOINT;
+                       break;
+               }
+
                ret = ust_app_calibrate_glb(&ucalibrate);
                if (ret < 0) {
                        ret = LTTNG_ERR_UST_CALIBRATE_FAIL;
@@ -2280,6 +2322,21 @@ int cmd_data_pending(struct ltt_session *session)
        if (session->enabled) {
                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->started) {
+                       ret = 0;
+                       goto error;
+               }
        }
 
        if (ksess && ksess->consumer) {
@@ -2632,12 +2689,17 @@ static int record_ust_snapshot(struct ltt_ust_session *usess,
 
        ret = ust_app_snapshot_record(usess, output, wait, nb_streams);
        if (ret < 0) {
-               if (ret == -EINVAL) {
+               switch (-ret) {
+               case EINVAL:
                        ret = LTTNG_ERR_INVALID;
-                       goto error_snapshot;
+                       break;
+               case ENODATA:
+                       ret = LTTNG_ERR_SNAPSHOT_NODATA;
+                       break;
+               default:
+                       ret = LTTNG_ERR_SNAPSHOT_FAIL;
+                       break;
                }
-
-               ret = LTTNG_ERR_SNAPSHOT_FAIL;
                goto error_snapshot;
        }