On Thu, Mar 26, 2015 at 05:38:45PM +0000, Morten Rasmussen wrote: > Another potential solution is to stay with weak functions but move the > multiplication and shift into the arch_scale_*() functions by passing > the value we want to scale into the arch_scale_*() function. That way we > can completely avoid multiplication and shift in the default case (no > arch_scale*() implementations, which is better than what we have today. > > The only downside is that for frequency invariance we need three > arch_scale_freq_capacity() calls instead of two.
That would still result in unconditional function calls, which on some archs are _more_ expensive than 64bit mults. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/