On 1/16/2024 3:55 PM, Johannes Thumshirn wrote:
> On 16.01.24 10:52, Kanchan Joshi wrote:
>>> + if (!plug)
>>> + return ktime_get_ns();
>>> + if (!(plug->cur_ktime & 1ULL)) {
>>> + plug->cur_ktime = ktime_get_ns();
>>> + plug->cur_ktime |= 1ULL;
>>> + }
>>> + return plug->cur_ktime;
>>
>> I did not understand the relevance of 1ULL here.
>> If ktime_get_ns() returns even value, it will turn that into an odd
>> value before caching. And that value will be returned for the subsequent
>> calls.
>> But how is that better compared to just caching whatever ktime_get_ns()
>> returned.
>>
>>
>
> IIUC it's an indicator if plug->cur_ktime has been set or not.
> But I don't understand why we can't compare with 0?
Yes, that's what I meant by 'just caching whatever ktime_get_ns() returned'.
if (!plug->cur_ktime)
plug->cur_ktime = ktime_get_ns();
An indicator should not alter the return (unless there is a reason).
