Re: Re: Re: Re: [PATCH v4 5/5] perf/sdt: Add support to perf record to trace SDT events

[Arnaldo Carvalho de Melo <acme@redhat.com>]

Em Wed, Nov 05, 2014 at 06:07:08PM +0900, Masami Hiramatsu escreveu:
> (2014/11/05 15:50), Hemant Kumar wrote:
> >> And also, user interface is a discussion point. This series defines new
> >> sdt-cache command, and we already have buildid-cache command. We should
> >> have probe-cache command too? or consolidate those cache managing 
> >> commands?
> >> This question should be involving your series too.

> > I think, we need not have multiple sub-commands to manage the cache. We 
> > can consolidate the cache management of probe events (including SDT 
> > events) to a single command.

> Agreed. maybe perf-cache --buildid/--sdt/--probe would be good.

We have it already, its called 'perf buildid-cache':

[root@zoo ~]# perf buildid-cache --hell
  Error: unknown option `hell'

 usage: perf buildid-cache [<options>]

    -a, --add <file list>
                          file(s) to add
    -k, --kcore <file>    kcore file to add
    -r, --remove <file list>
                          file(s) to remove
    -M, --missing <file>  to find missing build ids in the cache
    -f, --force           don't complain, do it
    -u, --update <file list>
                          file(s) to update
    -v, --verbose         be more verbose

[root@zoo ~]#

We can rename it at some point to 'perf cache', perhaps.

'perf cache --buildid'  makes no sense, everything is keyed by build-id
(hence the name, which is albeit long, admit), I guess what you meant
was 'elf'.

It currently stores content of the form:

- ELF
- kcore (which is also ELF, but has no pathname)
- kallsyms

We would be adding other types of content, from this discussion:

- sdt
- [ku]probes (built from some other content, like ELF or kallsyms)
 
- Arnaldo