On Mon, May 19, 2025 at 12:08:37PM -0400, Steven Rostedt wrote:

On Mon, 19 May 2025 16:12:39 +0100
Will Deacon [off-list ref] wrote:

quoted

quoted

Perf events work for perf only. My question is why isn't this a tracepoint
that perf could hook into?  

Well, the perf event came first in this case, so we're stuck with it :/

I wonder what effort it will take to convert perf events to tracepoints ;-)

Note, I'm talking about tracepoints and not trace events, where the
latter is exposed to tracefs and the former is not.

quoted

I was hoping we could settle for a generic helper that could emit both
the trace event and the perf event (so that the ordering of the two is
portable across architectures) but, judging by Nam's reply, the trace
event is needed before kprobes gets a look in.

Perhaps we could add a helper function that does both (perf and
tracepoint) and hide the implementation from the code that calls it?

Something like that sounds like a good idea, yes.

But I'm currently still on PTO so I haven't looked at the details yet.

Enjoy!

Will