Messages in this thread | | | Date | Fri, 27 Mar 2015 17:15:34 -0300 | From | Arnaldo Carvalho de Melo <> | Subject | Re: [PATCH] perf, record: Add clockid parameter |
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Em Fri, Mar 27, 2015 at 11:35:25AM -0600, David Ahern escreveu: > On 3/27/15 11:20 AM, Peter Zijlstra wrote: > >>This is a new feature which means use_clockid on older kernels will fail. So > >>need to catch that and throw an error -- perhaps yet another probe function.
> >How does that work? What do I grep to find an example? I figured if the > >kernel didn't support the syscall will fail and we'll terminate > >someplace.
> Look at __perf_evsel__open(). In this case you probably do not want > to fallback but tell the user the clock id option is not supported. > The problem is deciphering the failure is due to the clock id versus > all the other failure reasons.
I.e. we're back to the sys_perf_event_open() error reporting suckz rockz thing, this time with PeterZ trying to find a way to avoid getting back to that discussion... /me runz... ;-P
- Arnaldo
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