Sorry that I don't get this one, did you mean kernel subsystems like
bpf or third party modules?  Honestly I don't know how it works here
for userspace to consume the raw tracepoint without looking at
tracefs.

Regards,
Ze

On Tue, Aug 1, 2023 at 7:46 PM Peter Zijlstra [off-list ref] wrote:

On Tue, Aug 01, 2023 at 05:01:21PM +0800, Ze Gao wrote:

quoted

@@ -233,6 +255,7 @@ TRACE_EVENT(sched_switch,
              __field(        pid_t,  prev_pid                        )
              __field(        int,    prev_prio                       )
              __field(        long,   prev_state                      )
+             __field(        char,   prev_state_char                 )
              __array(        char,   next_comm,      TASK_COMM_LEN   )
              __field(        pid_t,  next_pid                        )
              __field(        int,    next_prio                       )

And this again will wreck everybody that consumes the raw tracepoint
without looking at tracefs.