Re: [PATCH 1/3] perf, tools: Add override support for event list CPUID

[Jiri Olsa <jolsa@redhat.com>]

On Sun, May 31, 2015 at 09:11:34AM -0700, Andi Kleen wrote:
> From: Andi Kleen <ak@linux.intel.com>
> 
> Add a PERF_CPUID variable to override the CPUID of the current CPU.
> This is useful for testing, so that all event lists 

.. within a current architecture (x86, powerpc) ..

> can be tested on a single
> system.
> 
> v2: Fix double free in earlier version.
> Signed-off-by: Andi Kleen <ak@linux.intel.com>
> ---
>  tools/perf/util/pmu.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
> index 578a537..5c30f89 100644
> --- a/tools/perf/util/pmu.c
> +++ b/tools/perf/util/pmu.c
> @@ -474,7 +474,11 @@ static int pmu_add_cpu_aliases(void *data)
>  	struct pmu_event *pe;
>  	char *cpuid;
>  
> -	cpuid = get_cpuid_str();
> +	cpuid = getenv("PERF_CPUID");
> +	if (cpuid)
> +		cpuid = strdup(cpuid);
> +	if (!cpuid)
> +		cpuid = get_cpuid_str();
>  	if (!cpuid)
>  		return 0;

I tried and it's hard to actually say you're looking on another
CPU events. Could we advertise the CPUID in perf list? Or at least
some pr_debug print.

thanks,
jirka