Re: [PATCH v2] perf/sdt: Show proper hint

From: Arnaldo Carvalho de Melo
Date: Fri Feb 03 2017 - 10:18:47 EST


Em Fri, Feb 03, 2017 at 03:56:42PM +0530, Ravi Bangoria escreveu:
> After patch:
> $ perf record -a -e sdt_glib:idle__add
> event syntax error: 'sdt_glib:idle__add'
> \___ unknown tracepoint
>
> Error: File /sys/kernel/debug/tracing/events/sdt_glib/idle__add not found.
> Hint: SDT event cannot be directly recorded on. Please use 'perf probe sdt_glib:idle__add' before recording it.
> ...
>
> $ perf probe sdt_glib:idle__add
> Added new event:
> sdt_glib:idle__add (on %idle__add in /usr/lib64/libglib-2.0.so.0.5000.2)
>
> You can now use it in all perf tools, such as:
>
> perf record -e sdt_glib:idle__add -aR sleep 1
>
> $ perf record -a -e sdt_glib:idle__add
> [ perf record: Woken up 1 times to write data ]
> [ perf record: Captured and wrote 0.175 MB perf.data ]

Looks much better! Thanks!

Unsure if we should state somewhere that this needs to be done only once
per boot.

Ingo, are you ok now? Ack?

- Arnaldo