Hi Jiri,
On Mon, 3 Feb 2014 12:44:41 +0100, Jiri Olsa wrote:
> We use PERF_SAMPLE_PERIOD sample type only for frequency
> setup -F (default) option. The -c does not need store period,
> because it's always the same.
>
> In -c case the report code uses '1' as period. Fixing
> it to perf_event_attr::sample_period.
All 3 patches look good. But I found something strange. When we
setup/config evsel attrs following code is used:
util/evsel.c::perf_evsel__config()
/*
* We default some events to a 1 default interval. But keep
* it a weak assumption overridable by the user.
*/
if (!attr->sample_period || (opts->user_freq != UINT_MAX &&
opts->user_interval != ULLONG_MAX)) {
if (opts->freq) {
perf_evsel__set_sample_bit(evsel, PERIOD);
attr->freq = 1;
attr->sample_freq = opts->freq;
} else {
attr->sample_period = opts->default_interval;
}
}
But shouldn't it be "||" instead of "&&" for checking
user_freq/interval? The opts->freq was setup by code below
util/record.c::record_opts__config_freq()
bool user_freq = opts->user_freq != UINT_MAX;
unsigned int max_rate;
if (opts->user_interval != ULLONG_MAX)
opts->default_interval = opts->user_interval;
if (user_freq)
opts->freq = opts->user_freq;
/*
* User specified count overrides default frequency.
*/
if (opts->default_interval)
opts->freq = 0;
else if (opts->freq) {
opts->default_interval = opts->freq;
} else {
pr_err("frequency and count are zero, aborting\n");
return -1;
}
Thanks,
Namhyung
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