Add enable/disable per event/channel/session (new ABI)

[lttng-modules.git] / ltt-events.c

diff --git a/ltt-events.c b/ltt-events.c
index ffcc61ec65d5657fb03a0e0ca7958cb1df43f60f..a94e8f9a1dde6a6e315133e59c66e3659455f99d 100644 (file)
--- a/ltt-events.c
+++ b/ltt-events.c
@@ -82,7 +82,7 @@ void ltt_session_destroy(struct ltt_session *session)
        kfree(session);
 }
 
-int ltt_session_start(struct ltt_session *session)
+int ltt_session_enable(struct ltt_session *session)
 {
        int ret = 0;
        struct ltt_channel *chan;
@@ -119,7 +119,7 @@ end:
        return ret;
 }
 
-int ltt_session_stop(struct ltt_session *session)
+int ltt_session_disable(struct ltt_session *session)
 {
        int ret = 0;
 
@@ -135,6 +135,46 @@ end:
        return ret;
 }
 
+int ltt_channel_enable(struct ltt_channel *channel)
+{
+       int old;
+
+       old = xchg(&channel->enabled, 1);
+       if (old)
+               return -EEXIST;
+       return 0;
+}
+
+int ltt_channel_disable(struct ltt_channel *channel)
+{
+       int old;
+
+       old = xchg(&channel->enabled, 0);
+       if (!old)
+               return -EEXIST;
+       return 0;
+}
+
+int ltt_event_enable(struct ltt_event *event)
+{
+       int old;
+
+       old = xchg(&event->enabled, 1);
+       if (old)
+               return -EEXIST;
+       return 0;
+}
+
+int ltt_event_disable(struct ltt_event *event)
+{
+       int old;
+
+       old = xchg(&event->enabled, 0);
+       if (!old)
+               return -EEXIST;
+       return 0;
+}
+
 static struct ltt_transport *ltt_transport_find(const char *name)
 {
        struct ltt_transport *transport;
@@ -169,7 +209,6 @@ struct ltt_channel *ltt_channel_create(struct ltt_session *session,
        if (!chan)
                goto nomem;
        chan->session = session;
-       init_waitqueue_head(&chan->notify_wait);
        chan->id = session->free_chan_id++;
        /*
         * Note: the channel creation op already writes into the packet
@@ -181,6 +220,7 @@ struct ltt_channel *ltt_channel_create(struct ltt_session *session,
                        read_timer_interval);
        if (!chan->chan)
                goto create_error;
+       chan->enabled = 1;
        chan->ops = &transport->ops;
        list_add(&chan->list, &session->chan);
        mutex_unlock(&sessions_mutex);
@@ -233,6 +273,7 @@ struct ltt_event *ltt_event_create(struct ltt_channel *chan,
        event->chan = chan;
        event->filter = filter;
        event->id = chan->free_event_id++;
+       event->enabled = 1;
        event->instrumentation = event_param->instrumentation;
        /* Populate ltt_event structure before tracepoint registration. */
        smp_wmb();
@@ -385,7 +426,7 @@ int lttng_metadata_printf(struct ltt_session *session,
                 * we need to bail out after timeout or being
                 * interrupted.
                 */
-               waitret = wait_event_interruptible_timeout(*chan->ops->get_reader_wait_queue(chan),
+               waitret = wait_event_interruptible_timeout(*chan->ops->get_reader_wait_queue(chan->chan),
                        ({
                                ret = chan->ops->event_reserve(&ctx, 0);
                                ret != -ENOBUFS || !ret;
@@ -399,7 +440,7 @@ int lttng_metadata_printf(struct ltt_session *session,
                                ret = waitret;
                        goto end;
                }
-               chan->ops->event_write(&ctx, &str[pos], len);
+               chan->ops->event_write(&ctx, &str[pos], reserve_len);
                chan->ops->event_commit(&ctx);
        }
 end: