Add kernel snapshot support

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

diff --git a/src/bin/lttng-sessiond/kernel.c b/src/bin/lttng-sessiond/kernel.c
index 154b2d62306df654d63a148ebf5005bc6d09218c..1ba6b16e6a70e3d1b66c55bfd89aaa5882c3acfb 100644 (file)
--- a/src/bin/lttng-sessiond/kernel.c
+++ b/src/bin/lttng-sessiond/kernel.c
@@ -754,6 +754,32 @@ void kernel_destroy_session(struct ltt_kernel_session *ksess)
 
        DBG("Tearing down kernel session");
 
+       /*
+        * Destroy channels on the consumer if in no output mode because the
+        * streams are in *no* monitor mode so we have to send a command to clean
+        * them up or else they leaked.
+        */
+       if (!ksess->output_traces) {
+               int ret;
+               struct consumer_socket *socket;
+               struct lttng_ht_iter iter;
+
+               /* For each consumer socket. */
+               cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
+                               socket, node.node) {
+                       struct ltt_kernel_channel *chan;
+
+                       /* For each channel, ask the consumer to destroy it. */
+                       cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
+                               ret = kernel_consumer_destroy_channel(socket, chan);
+                               if (ret < 0) {
+                                       /* Consumer is probably dead. Use next socket. */
+                                       continue;
+                               }
+                       }
+               }
+       }
+
        /* Close any relayd session */
        consumer_output_send_destroy_relayd(ksess->consumer);
 
@@ -844,10 +870,9 @@ int kernel_snapshot_record(struct ltt_kernel_session *ksess,
 
                pthread_mutex_lock(socket->lock);
                /* This stream must not be monitored by the consumer. */
-               ret = kernel_consumer_add_metadata(socket, ksess, 1);
-               ret = 0;
+               ret = kernel_consumer_add_metadata(socket, ksess, 0);
                pthread_mutex_unlock(socket->lock);
-               /* Put back the savec consumer output into the session. */
+               /* Put back the saved consumer output into the session. */
                ksess->consumer = saved_output;
                if (ret < 0) {
                        ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
@@ -856,8 +881,10 @@ int kernel_snapshot_record(struct ltt_kernel_session *ksess,
 
                /* For each channel, ask the consumer to snapshot it. */
                cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
+                       pthread_mutex_lock(socket->lock);
                        ret = consumer_snapshot_channel(socket, chan->fd, output, 0,
                                        ksess->uid, ksess->gid, wait);
+                       pthread_mutex_unlock(socket->lock);
                        if (ret < 0) {
                                ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
                                goto error_consumer;
@@ -865,12 +892,20 @@ int kernel_snapshot_record(struct ltt_kernel_session *ksess,
                }
 
                /* Snapshot metadata, */
+               pthread_mutex_lock(socket->lock);
                ret = consumer_snapshot_channel(socket, ksess->metadata->fd, output,
                                1, ksess->uid, ksess->gid, wait);
+               pthread_mutex_unlock(socket->lock);
                if (ret < 0) {
                        ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
                        goto error_consumer;
                }
+
+               /*
+                * The metadata snapshot is done, ask the consumer to destroy it since
+                * it's not monitored on the consumer side.
+                */
+               (void) kernel_consumer_destroy_metadata(socket, ksess->metadata);
        }
 
 error_consumer: