Re: [PATCH 09/44] perf session: Add instruction tracing options

[Adrian Hunter <adrian.hunter@intel.com>]

On 21/04/15 17:50, Arnaldo Carvalho de Melo wrote:
> Em Thu, Apr 09, 2015 at 06:53:49PM +0300, Adrian Hunter escreveu:
> 
>> It is assumed that AUX area decoding will synthesize events for
>> consumption by other tools.  At this time, the main use of AUX area
>> tracing will be to capture instruction trace (aka processor trace)
>> data.  The nature of instruction tracing suggests the initial
>> inclusion of options for "instructions" and "branches" events, but
>> more could be added as needed.
>  
>> +++ b/tools/perf/util/auxtrace.c
>> @@ -37,6 +37,7 @@
>>  
>>  #include "event.h"
>>  #include "debug.h"
>> +#include "parse-options.h"
>>  
>>  int auxtrace_mmap__mmap(struct auxtrace_mmap *mm,
>>  			struct auxtrace_mmap_params *mp,
>> @@ -200,6 +201,136 @@ out_free:
>>  	return err;
>>  }
>>  
>> +#define PERF_ITRACE_DEFAULT_PERIOD_TYPE		PERF_ITRACE_PERIOD_NANOSECS
>> +#define PERF_ITRACE_DEFAULT_PERIOD		100000
>> +#define PERF_ITRACE_DEFAULT_CALLCHAIN_SZ	16
>> +#define PERF_ITRACE_MAX_CALLCHAIN_SZ		1024
>> +
>> +void itrace_synth_opts__set_default(struct itrace_synth_opts *synth_opts)
>> +{
>> +	synth_opts->instructions = true;
>> +	synth_opts->branches = true;
>> +	synth_opts->errors = true;
>> +	synth_opts->period_type = PERF_ITRACE_DEFAULT_PERIOD_TYPE;
>> +	synth_opts->period = PERF_ITRACE_DEFAULT_PERIOD;
>> +	synth_opts->callchain_sz = PERF_ITRACE_DEFAULT_CALLCHAIN_SZ;
>> +}
>> +
>> +int itrace_parse_synth_opts(const struct option *opt, const char *str,
>> +			    int unset)
>> +{
>> +	struct itrace_synth_opts *synth_opts = opt->value;
>> +	const char *p;
>> +	char *endptr;
>> +
>> +	synth_opts->set = true;
>> +
>> +	if (unset) {
>> +		synth_opts->dont_decode = true;
>> +		return 0;
>> +	}
>> +
>> +	if (!str) {
>> +		itrace_synth_opts__set_default(synth_opts);
>> +		return 0;
>> +	}
>> +
>> +	for (p = str; *p;) {
>> +		switch (*p++) {
>> +		case 'i':
>> +			synth_opts->instructions = true;
> 
> Is this documented anywhere? I.e. examples for setting up this synth
> ops?

They are documented for each tool that uses them:
	Documentation/perf-script.txt
	Documentation/perf-record.txt
and also in:
	Documentation/intel-pt.txt