Re: [PATCH v0 3/5] perf: Introduce instruction trace filtering

[Alexander Shishkin <alexander.shishkin@linux.intel.com>]

Peter Zijlstra <peterz@infradead.org> writes:

> On Fri, Dec 11, 2015 at 03:36:36PM +0200, Alexander Shishkin wrote:
>
>> The pmu driver interface basically adds an extra callback to the
>> pmu driver structure, which validates the filter configuration proposed
>> by the user against what the hardware is actually capable of doing
>> and translates it into something that pmu::start can program into
>> hardware.
>
>> @@ -388,12 +393,38 @@ struct pmu {
>>  	void (*free_aux)		(void *aux); /* optional */
>>  
>>  	/*
>> +	 * Validate instruction tracing filters: make sure hw supports the
>> +	 * requested configuration and number of filters.
>> +	 *
>> +	 * Configure instruction tracing filters: translate hw-agnostic filter
>> +	 * into hardware configuration in event::hw::itrace_filters
>> +	 */
>> +	int (*itrace_filter_setup)	(struct perf_event *event); /* optional */
>> +
>> +	/*
>>  	 * Filter events for PMU-specific reasons.
>>  	 */
>>  	int (*filter_match)		(struct perf_event *event); /* optional */
>>  };
>
> Any reason you cannot use pmu::filter_match ?

It's for filtering out events that we want to skip over while iterating
various event lists, it's also used in quite a few places (which are
also relevant to our pmus), so I couldn't see how to re-use it.

Thanks,
--
Alex