Implement UST destroy session

[lttng-tools.git] / lttng-sessiond / ust-consumer.c

diff --git a/lttng-sessiond/ust-consumer.c b/lttng-sessiond/ust-consumer.c
index 605870d52028c77f852ef6b6b091e24047d97cd2..866d7bd56bc199e8bed90b2e3abc1ec88f48a070 100644 (file)
--- a/lttng-sessiond/ust-consumer.c
+++ b/lttng-sessiond/ust-consumer.c
@@ -36,11 +36,9 @@
 static int send_channel_streams(int sock,
                struct ust_app_channel *uchan)
 {
-       int ret, fds[2];
-       struct ltt_ust_stream *stream;
+       int ret, fd;
        struct lttcomm_consumer_msg lum;
-       struct cds_lfht_iter iter;
-       struct cds_lfht_node *node;
+       struct ltt_ust_stream *stream, *tmp;
 
        DBG("Sending streams of channel %s to UST consumer", uchan->name);
 
@@ -48,8 +46,11 @@ static int send_channel_streams(int sock,
        lum.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
 
        /*
-        * We need to keep shm_fd open to make sure this key stays unique within
-        * the session daemon.
+        * We need to keep shm_fd open while we transfer the stream file
+        * descriptors to make sure this key stays unique within the
+        * session daemon. We can free the channel shm_fd without
+        * problem after we finished sending stream fds for that
+        * channel.
         */
        lum.u.channel.channel_key = uchan->obj->shm_fd;
        lum.u.channel.max_sb_size = uchan->attr.subbuf_size;
@@ -60,31 +61,28 @@ static int send_channel_streams(int sock,
                perror("send consumer channel");
                goto error;
        }
-       fds[0] = uchan->obj->shm_fd;
-       fds[1] = uchan->obj->wait_fd;
-       ret = lttcomm_send_fds_unix_sock(sock, fds, 2);
+       fd = uchan->obj->shm_fd;
+       ret = lttcomm_send_fds_unix_sock(sock, &fd, 1);
        if (ret < 0) {
                perror("send consumer channel ancillary data");
                goto error;
        }
 
-
-       rcu_read_lock();
-       hashtable_get_first(uchan->streams, &iter);
-       while ((node = hashtable_iter_get_node(&iter)) != NULL) {
-               stream = caa_container_of(node, struct ltt_ust_stream, node);
-
+       cds_list_for_each_entry_safe(stream, tmp, &uchan->streams.head, list) {
                int fds[2];
 
                if (!stream->obj->shm_fd) {
-                       goto next;
+                       continue;
                }
-
                lum.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
                lum.u.stream.channel_key = uchan->obj->shm_fd;
                lum.u.stream.stream_key = stream->obj->shm_fd;
                lum.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
-               lum.u.stream.output = uchan->attr.output;
+               /*
+                * FIXME Hack alert! we force MMAP for now. Mixup
+                * between EVENT and UST enums elsewhere.
+                */
+               lum.u.stream.output = DEFAULT_UST_CHANNEL_OUTPUT;
                lum.u.stream.mmap_len = stream->obj->memory_map_size;
                strncpy(lum.u.stream.path_name, stream->pathname, PATH_MAX - 1);
                lum.u.stream.path_name[PATH_MAX - 1] = '\0';
@@ -102,11 +100,7 @@ static int send_channel_streams(int sock,
                        perror("send consumer stream ancillary data");
                        goto error;
                }
-
-next:
-               hashtable_get_next(uchan->streams, &iter);
        }
-       rcu_read_unlock();
 
        DBG("consumer channel streams sent");
 
@@ -131,22 +125,22 @@ int ust_consumer_send_session(int consumer_fd, struct ust_app_session *usess)
        DBG("Sending metadata stream fd");
 
        if (usess->metadata->obj->shm_fd != 0) {
+               int fd;
                int fds[2];
 
                /* Send metadata channel fd */
                lum.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
                lum.u.channel.channel_key = usess->metadata->obj->shm_fd;
                lum.u.channel.max_sb_size = usess->metadata->attr.subbuf_size;
-               lum.u.channel.mmap_len = 0;     /* for kernel */
+               lum.u.channel.mmap_len = usess->metadata->obj->memory_map_size;
                DBG("Sending metadata channel %d to consumer", lum.u.channel.channel_key);
                ret = lttcomm_send_unix_sock(sock, &lum, sizeof(lum));
                if (ret < 0) {
                        perror("send consumer channel");
                        goto error;
                }
-               fds[0] = usess->metadata->obj->shm_fd;
-               fds[1] = usess->metadata->obj->wait_fd;
-               ret = lttcomm_send_fds_unix_sock(sock, fds, 2);
+               fd = usess->metadata->obj->shm_fd;
+               ret = lttcomm_send_fds_unix_sock(sock, &fd, 1);
                if (ret < 0) {
                        perror("send consumer metadata channel");
                        goto error;
@@ -184,6 +178,7 @@ int ust_consumer_send_session(int consumer_fd, struct ust_app_session *usess)
 
                ret = send_channel_streams(sock, uchan);
                if (ret < 0) {
+                       rcu_read_unlock();
                        goto error;
                }
                hashtable_get_next(usess->channels, &iter);