Re: [PATCH] drm/i915: compute wait_ioctl timeout correctly

John Stultz
2014-12-03T19:07:09Z

On Wed, Dec 3, 2014 at 6:30 AM, Daniel Vetter <daniel@ffwll.ch> wrote:
> On Tue, Dec 02, 2014 at 08:54:13AM -0800, John Stultz wrote:
>> On Tue, Dec 2, 2014 at 8:35 AM, Chris Wilson <chris@chris-wilson.co.uk> wrote:
>> > On Tue, Dec 02, 2014 at 04:36:22PM +0100, Daniel Vetter wrote:
>> >> +static inline unsigned long nsecs_to_jiffies_timeout(const u64 m)
>> >> +{
>> >> + u64 usecs = div_u64(m + 999, 1000);
>> >> + unsigned long j = usecs_to_jiffies(usecs);
>> >> +
>> >> + return min_t(unsigned long, MAX_JIFFY_OFFSET, j + 1);
>> >
>> > Or more concisely and review friendly:
>> >
>> > static inline unsigned long nsecs_to_jiffies_timeout(const u64 n)
>> > {
>> > return min_t(u64, MAX_JIFFY_OFFSET, nsecs_to_jiffies64(n) + 1);
>> > }
>>
>> Yea. This looks much nicer. Seems generic enough it might be better
>> added next to nsec_to_jiffies64() in kernel/time/time.c or jiffies.h
>> rather then in a driver header.
>
> Ok, that needs an EXPORT_SYMBOL for nsecs_to_jiffies64. Can I count your
> "Yea" above as an ack for adding that and pulling it in through
> drm-intel.git?

Do you need an EXPORT_SYMBOL if you add the _timeout version next to
nsecs_to_jiffies64 in time.c?

Otherwise no objections to the approach, but I'd like to properly do
an Acked-by: after I see the patch. :)

thanks
-john