[ltt-dev] TODO list before releasing LTTng-buffering to LKML]

[zhaolei@cn.fujitsu.com (Zhaolei)]

Hello, Mathieu.

>> Are you means we can control each channel's (interrupt, process, ...) subbuf in future version?
>> (I think current version can only control low, med and high)
>> If this is true, maybe we need modify ltt_trace_create() before impl ltt_control.
>> 
> Yes, this is the goal.
So, IMHO, we can do it in following steps:

Step1: modify ltt_trace_create(), .etc, separate ltt_trace_create() into
  ltt_trace_setup(), ltt_set_channelsize(), ltt_set_channelnum(),
  ltt_trace_alloc(). But still use old netlink_based ltt_control to make
  it simple. 
  Although we modify ltt_set_channelsize() to support setting each channel's
  buffer, we make ltt_control.ko using old UI(only able to set low, med and
  high). So we don't need to modify other program such as user-mode lttctl.

Step2: Write a new module named ltt-channel-control.
  ( I think name of ltt-channel-control will be better than ltt-control,
    because we already have a module named ltt-marker-control. )
  ltt-channel-control is designed on debugfs, as we discussed.
  We can test it by echo XX > /mnt/debugfs/ltt/...

Step3: modify user-mode programs to support ltt-channel-control.
  We also need to modify lttctl's command arguments, to support setup each
  channel's buffer. (Are we take out -Z, -X, -V, -B, -z, -x in lttctl?)
  I haven't read source of lttv, it is necessary to modify?

B.R.
Zhaolei