Re: [PATCH] tracing: Allow creating instances with specified system events

On Tue, 5 Dec 2023 19:13:09 +0100
Dmytro Maluka [off-list ref] wrote:

On Tue, Nov 28, 2023 at 12:21:17PM -0500, Steven Rostedt wrote:

quoted

From: "Steven Rostedt (Google)" <rostedt@goodmis.org>

A trace instance may only need to enable specific events. As the eventfs
directory of an instance currently creates all events which adds overhead,
allow internal instances to be created with just the events in systems
that they care about. This currently only deals with systems and not
individual events, but this should bring down the overhead of creating
instances for specific use cases quite bit.

The trace_array_get_by_name() now has another parameter "systems". This
parameter is a const string pointer of a comma/space separated list of
event systems that should be created by the trace_array. (Note if the
trace_array already exists, this parameter is ignored).

The list of systems is saved and if a module is loaded, its events will
not be added unless the system for those events also match the systems
string.

Note that all dynamic events are still added as they are created by the
user.

Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---  

Tested-by: Dmytro Maluka <redacted>

Thanks, but I have a v2 of this patch on my local repository, as after
discussing with Masami, I decided not to allow dynamic events unless they
are specified.

I'll send the v2 out later today.

-- Steve