Fix: race with the viewer and readiness of streams

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

diff --git a/src/bin/lttng-sessiond/kernel-consumer.c b/src/bin/lttng-sessiond/kernel-consumer.c
index ef6dccb538219c86b70615b5323c00697f5a510d..4c069588a36cf36ce8755433f2f03c480df06ba4 100644 (file)
--- a/src/bin/lttng-sessiond/kernel-consumer.c
+++ b/src/bin/lttng-sessiond/kernel-consumer.c
@@ -26,7 +26,7 @@
 #include <common/defaults.h>
 
 #include "consumer.h"
-#include "health.h"
+#include "health-sessiond.h"
 #include "kernel-consumer.h"
 
 static char *create_channel_path(struct consumer_output *consumer,
@@ -123,7 +123,8 @@ int kernel_consumer_add_channel(struct consumer_socket *sock,
                        CONSUMER_CHANNEL_TYPE_DATA,
                        channel->channel->attr.tracefile_size,
                        channel->channel->attr.tracefile_count,
-                       monitor);
+                       monitor,
+                       channel->channel->attr.live_timer_interval);
 
        health_code_update();
 
@@ -184,7 +185,7 @@ int kernel_consumer_add_metadata(struct consumer_socket *sock,
                        DEFAULT_KERNEL_CHANNEL_OUTPUT,
                        CONSUMER_CHANNEL_TYPE_METADATA,
                        0, 0,
-                       monitor);
+                       monitor, 0);
 
        health_code_update();
 
@@ -202,14 +203,6 @@ int kernel_consumer_add_metadata(struct consumer_socket *sock,
                        session->metadata_stream_fd,
                        0); /* CPU: 0 for metadata. */
 
-       /*
-        * Set the no monitor flag. If set to 1, it indicates the consumer to NOT
-        * monitor the stream but rather add it to a special list in the associated
-        * channel. This is used to handle ephemeral stream used by the snapshot
-        * command or store streams for the flight recorder mode.
-        */
-       lkm.u.stream.no_monitor = no_monitor;
-
        health_code_update();
 
        /* Send stream and file descriptor */
@@ -269,6 +262,40 @@ error:
        return ret;
 }
 
+/*
+ * Sending the notification that all streams were sent with STREAMS_SENT.
+ */
+int kernel_consumer_streams_sent(struct consumer_socket *sock,
+               struct ltt_kernel_session *session, uint64_t channel_key)
+{
+       int ret;
+       struct lttcomm_consumer_msg lkm;
+       struct consumer_output *consumer;
+
+       assert(sock);
+       assert(session);
+
+       DBG("Sending streams_sent");
+       /* Get consumer output pointer */
+       consumer = session->consumer;
+
+       /* Prep stream consumer message */
+       consumer_init_streams_sent_comm_msg(&lkm,
+                       LTTNG_CONSUMER_STREAMS_SENT,
+                       channel_key, consumer->net_seq_index);
+
+       health_code_update();
+
+       /* Send stream and file descriptor */
+       ret = consumer_send_msg(sock, &lkm);
+       if (ret < 0) {
+               goto error;
+       }
+
+error:
+       return ret;
+}
+
 /*
  * Send all stream fds of kernel channel to the consumer.
  */
@@ -278,6 +305,7 @@ int kernel_consumer_send_channel_stream(struct consumer_socket *sock,
 {
        int ret;
        struct ltt_kernel_stream *stream;
+       uint64_t channel_key = -1ULL;
 
        /* Safety net */
        assert(channel);
@@ -311,8 +339,22 @@ int kernel_consumer_send_channel_stream(struct consumer_socket *sock,
                if (ret < 0) {
                        goto error;
                }
+               if (channel_key == -1ULL) {
+                       channel_key = channel->fd;
+               }
+       }
+
+       if (!monitor || channel_key == -1ULL) {
+               goto end;
+       }
+
+       /* Add stream on the kernel consumer side. */
+       ret = kernel_consumer_streams_sent(sock, session, channel_key);
+       if (ret < 0) {
+               goto error;
        }
 
+end:
 error:
        return ret;
 }
@@ -370,3 +412,59 @@ int kernel_consumer_send_session(struct consumer_socket *sock,
 error:
        return ret;
 }
+
+int kernel_consumer_destroy_channel(struct consumer_socket *socket,
+               struct ltt_kernel_channel *channel)
+{
+       int ret;
+       struct lttcomm_consumer_msg msg;
+
+       assert(channel);
+       assert(socket);
+
+       DBG("Sending kernel consumer destroy channel key %d", channel->fd);
+
+       msg.cmd_type = LTTNG_CONSUMER_DESTROY_CHANNEL;
+       msg.u.destroy_channel.key = channel->fd;
+
+       pthread_mutex_lock(socket->lock);
+       health_code_update();
+
+       ret = consumer_send_msg(socket, &msg);
+       if (ret < 0) {
+               goto error;
+       }
+
+error:
+       health_code_update();
+       pthread_mutex_unlock(socket->lock);
+       return ret;
+}
+
+int kernel_consumer_destroy_metadata(struct consumer_socket *socket,
+               struct ltt_kernel_metadata *metadata)
+{
+       int ret;
+       struct lttcomm_consumer_msg msg;
+
+       assert(metadata);
+       assert(socket);
+
+       DBG("Sending kernel consumer destroy channel key %d", metadata->fd);
+
+       msg.cmd_type = LTTNG_CONSUMER_DESTROY_CHANNEL;
+       msg.u.destroy_channel.key = metadata->fd;
+
+       pthread_mutex_lock(socket->lock);
+       health_code_update();
+
+       ret = consumer_send_msg(socket, &msg);
+       if (ret < 0) {
+               goto error;
+       }
+
+error:
+       health_code_update();
+       pthread_mutex_unlock(socket->lock);
+       return ret;
+}