Re: [RFC 7/7] net: don't check for active hrtimer after adding it

Viresh Kumar
2014-07-09T10:44:45Z

Hi Chris,

On 9 July 2014 16:02, Chris Redpath <Chris.Redpath@arm.com> wrote:

>> diff --git a/net/core/pktgen.c b/net/core/pktgen.c
>> index fc17a9d..f911acd 100644
>> --- a/net/core/pktgen.c
>> +++ b/net/core/pktgen.c
>> @@ -2186,8 +2186,6 @@ static void spin(struct pktgen_dev *pkt_dev, ktime_t
>> spin_until)
>> do {
>> set_current_state(TASK_INTERRUPTIBLE);
>> hrtimer_start_expires(&t.timer, HRTIMER_MODE_ABS);
>> - if (!hrtimer_active(&t.timer))
>> - t.task = NULL;
>>
>> if (likely(t.task))
>> schedule();
>
>
> I think this if condition can also be removed. hrtimer_init_sleeper copies
> the supplied task_struct * to the timer, which in this case is 'current'.
> The check is likely to be there in case of !active case you removed.

Yeah, it looks like we can get rid of this. Also,

} while (t.task && pkt_dev->running && !signal_pending(current));

is present in the closing "}" of do-while loop and probably we
don't need to check t.task here as well.

And this review comment applies to patch 2/7 as well:
hrtimer: don't check for active hrtimer after adding it

I would still wait for somebody to prove us wrong :), and will resend
it next week only.

Thanks.