Messages in this thread | | | Date | Tue, 05 Mar 2013 14:17:59 +0800 | From | John Stultz <> | Subject | Re: [RFC PATCH v2 0/4] Add support for S3 non-stop TSC support. |
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On 03/05/2013 12:32 PM, Jason Gunthorpe wrote: > On Tue, Mar 05, 2013 at 11:53:02AM +0800, Feng Tang wrote: > >>> // Drops some small precision along the way but is simple.. >>> static inline u64 cyclecounter_cyc2ns_128(const struct cyclecounter *cc, >>> cycle_t cycles) >>> { >>> u64 max = U64_MAX/cc->mult; >>> u64 num = cycles/max; >>> u64 result = num * ((max * cc->mult) >> cc->shift); >>> return result + cyclecounter_cyc2ns(cc, cycles - num*cc->mult); >>> } >> Your way is surely more accurate, if maintainers are ok with adding >> the new API, I will use it. > Okay, give it a good look though, I only wrote it out in email, never > tested it :) > Probably want to use clocksource instead of cyclecounter, but I think Jason's approach sounds ok. I might suggest that you initially make the function static to the timekeeping code, just so we don't get unexpected users.
thanks -john
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