On Tue, Aug 19, 2008 at 02:16:53PM -0400, Mathieu Desnoyers wrote:Question :
Is this kmemtrace marker meant to be exposed to userspace ?
I suspect not. In all case, not directly. I expect in-kernel probes to
be connected on these markers which will get the arguments they need,
and maybe access the inner data structures. Anyhow, tracepoints should
be used for that, not markers. You can later put markers in the probes
which are themselves connected to tracepoints.
Tracepoints = in-kernel tracing API.
Markers = Data-formatting tracing API, meant to export the data either
to user-space in text or binary format.
See
http://git.kernel.org/?p=linux/kernel/git/compudj/linux-2.6-lttng.git;a=shortlog
tracepoint-related patches.
I think we're ready to try tracepoints. Pekka, could you merge Mathieu's
tracepoints or otherwise provide a branch where I could submit a
tracepoint conversion patch for kmemtrace?