On Mon, 22 May 2017, Arnd Bergmann wrote: > On Sun, May 21, 2017 at 8:14 PM, Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote: > > But it's easy enough to provide them. All we need for that is something > > like > > > > unsigned long time_msec; > > > > which gets incremented every tick by the appropriate amount of > > milliseconds. > > > > Having that would also allow to replace all the > > > > end = jiffies + msec_to_jiffies(xxx); > > > > while (time_before(jiffies, end)) > > .... > > > > constructs with a milliseconds based machinery. So we can remove all > > *_to_jiffies() interfaces over time. > > A lot of those users could probably just ktime_get()/ktime_before() here, > as they would by definition not be performance critical. Right. > I don't see a way to just tk->tkr_mono.base but with a ktime_get_coarse() > we could just return the ktime_t of the last tick and not even need a seqlock > on 64-bit architectures, or have to introduce a new API. Yeah, that would be possible, but OTOH, for those loop thingies it probably does not matter at all whether you have the overhead of ktime_get() or not. We need to look at that stuff deeper. Thanks, tglx -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
