[RFC][PATCH 0/3] tracing: Make error_log per instance

From: Steven Rostedt
Date: Tue Apr 02 2019 - 14:34:57 EST


Hi Tom,

I noticed that you created an error_log file in every instance, but
they all show the same errors. These three patches make it so that
the errors appear in the instance directory that they happened in.
If you write a bad error to

/sys/kernel/tracing/instance/foo/events/sched/sched_switch/hist

It appears only in

/sys/kernel/tracing/instances/foo/error_log

Which I think is the proper approach, especially instances should not
affect the top directory or other instances.

For those errors that do not have an associated instance (creating a
kprobe/uprobe event or perf), a NULL passed to tracing_log_err() will
result in the error message in the top level error message.

Do you (or Masami) have any issues with this patch set?

If not, please add a "reviewed-by" or "acked-by" and I'll add it
to your patch series and push them to for-next (after more testing).

If this isn't obvious, this patch series is on top of:

http://lkml.kernel.org/r/cover.1554072478.git.tom.zanussi@xxxxxxxxxxxxxxx

Actually, I added it right after patch 5 of that series (before the
selftests and documentation).

Thanks!

-- Steve



Steven Rostedt (VMware) (3):
tracing: Add trace_array parameter to create_event_filter()
tracing: Have histogram code pass around trace_array for error handling
tracing: Have the error logs show up in the proper instances

----
kernel/trace/trace.c | 55 +++++++++-----
kernel/trace/trace.h | 8 +-
kernel/trace/trace_events_filter.c | 25 ++++---
kernel/trace/trace_events_hist.c | 145 ++++++++++++++++++++----------------
kernel/trace/trace_events_trigger.c | 3 +-
kernel/trace/trace_probe.c | 2 +-
6 files changed, 142 insertions(+), 96 deletions(-)