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

[lttng-modules.git] / ltt-debugfs-abi.c

diff --git a/ltt-debugfs-abi.c b/ltt-debugfs-abi.c
index fb6c789f1e0da0f4aa32bba7775fb86d439b90f0..53cc35d673c5e65a943e2dfea6ccbec96918ba8d 100644 (file)
--- a/ltt-debugfs-abi.c
+++ b/ltt-debugfs-abi.c
@@ -330,10 +330,10 @@ fd_error:
  *     This ioctl implements lttng commands:
  *     LTTNG_KERNEL_CHANNEL
  *             Returns a LTTng channel file descriptor
- *     LTTNG_KERNEL_SESSION_START
- *             Starts tracing session
- *     LTTNG_KERNEL_SESSION_STOP
- *             Stops tracing session
+ *     LTTNG_KERNEL_ENABLE
+ *             Enables tracing for a session (weak enable)
+ *     LTTNG_KERNEL_DISABLE
+ *             Disables tracing for a session (strong disable)
  *     LTTNG_KERNEL_METADATA
  *             Returns a LTTng metadata file descriptor
  *
@@ -350,9 +350,11 @@ long lttng_session_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
                                (struct lttng_kernel_channel __user *) arg,
                                PER_CPU_CHANNEL);
        case LTTNG_KERNEL_SESSION_START:
-               return ltt_session_start(session);
+       case LTTNG_KERNEL_ENABLE:
+               return ltt_session_enable(session);
        case LTTNG_KERNEL_SESSION_STOP:
-               return ltt_session_stop(session);
+       case LTTNG_KERNEL_DISABLE:
+               return ltt_session_disable(session);
        case LTTNG_KERNEL_METADATA:
                return lttng_abi_create_channel(file,
                                (struct lttng_kernel_channel __user *) arg,
@@ -506,6 +508,10 @@ fd_error:
  *             Returns an event file descriptor or failure.
  *     LTTNG_KERNEL_CONTEXT
  *             Prepend a context field to each event in the channel
+ *     LTTNG_KERNEL_ENABLE
+ *             Enable recording for events in this channel (weak enable)
+ *     LTTNG_KERNEL_DISABLE
+ *             Disable recording for events in this channel (strong disable)
  *
  * Channel and event file descriptors also hold a reference on the session.
  */
@@ -523,6 +529,10 @@ long lttng_channel_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
                return lttng_abi_add_context(file,
                                (struct lttng_kernel_context __user *) arg,
                                &channel->ctx, channel->session);
+       case LTTNG_KERNEL_ENABLE:
+               return ltt_channel_enable(channel);
+       case LTTNG_KERNEL_DISABLE:
+               return ltt_channel_disable(channel);
        default:
                return -ENOIOCTLCMD;
        }
@@ -564,10 +574,12 @@ unsigned int lttng_channel_poll(struct file *file, poll_table *wait)
        unsigned int mask = 0;
 
        if (file->f_mode & FMODE_READ) {
-               init_poll_funcptr(wait, wrapper_pollwait_exclusive);
+               poll_wait_set_exclusive(wait);
                poll_wait(file, channel->ops->get_hp_wait_queue(channel->chan),
                          wait);
 
+               if (channel->ops->is_disabled(channel->chan))
+                       return POLLERR;
                if (channel->ops->is_finalized(channel->chan))
                        return POLLHUP;
                else
@@ -612,13 +624,12 @@ static const struct file_operations lttng_metadata_fops = {
  *     @arg: command arg
  *
  *     This ioctl implements lttng commands:
- *      LTTNG_KERNEL_STREAM
- *              Returns an event stream file descriptor or failure.
- *              (typically, one event stream records events from one CPU)
- *     LTTNG_KERNEL_EVENT
- *             Returns an event file descriptor or failure.
  *     LTTNG_KERNEL_CONTEXT
  *             Prepend a context field to each record of this event
+ *     LTTNG_KERNEL_ENABLE
+ *             Enable recording for this event (weak enable)
+ *     LTTNG_KERNEL_DISABLE
+ *             Disable recording for this event (strong disable)
  */
 static
 long lttng_event_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
@@ -630,6 +641,10 @@ long lttng_event_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
                return lttng_abi_add_context(file,
                                (struct lttng_kernel_context __user *) arg,
                                &event->ctx, event->chan->session);
+       case LTTNG_KERNEL_ENABLE:
+               return ltt_event_enable(event);
+       case LTTNG_KERNEL_DISABLE:
+               return ltt_event_disable(event);
        default:
                return -ENOIOCTLCMD;
        }