Re: [PATCH i-g-t 7/8] tools/gputop: integrate i915 and xe PMU engine monitoring

[Jani Nikula <jani.nikula@intel.com>]

On Tue, 29 Sep 2026, Krzysztof Karas <krzysztof.karas@intel.com> wrote:
> Hi Sebastian,
>
> [...]
>
>> +static void pmu_devices_init(struct gputop_driver *drv,
>> +			     const struct device_operations *ops,
>> +			     const char *filter, size_t instance_size)
>> +{
>> +	struct igt_device_card *cards;
>> +	int n;
>> +
>> +	n = igt_device_card_match_all(filter, &cards);
>> +	if (n <= 0)
>> +		return;
>> +
>> +	drv->instances = calloc(n, instance_size);
>> +	if (!drv->instances) {
>> +		free(cards);
>> +		return;
>> +	}
>> +
>> +	drv->len = n;
>> +
>> +	for (int i = 0; i < n; i++) {
> I'll be pedantic here: iterators in this patch could be
> unsigned :)

Well, to be really pedantic, never use unsigned unless you really have
to.

Unsigned doesn't protect you from anything, and usually just lead to
trickier situations than using signed would. Use int when you can, and
it'll save you a lot of trouble.


BR,
Jani.



-- 
Jani Nikula, Intel