On 2018/12/19 5:38, Andi Kleen wrote: >> I misunderstood, you mean 32bit kernel, not 32bit machine. Theoretically >> 32bit >> kernel can use AVX512, but not sure if anyone use it like this. >> get_jiffies_64() >> includes jiffies_lock ops so not good in context switch. So I want to use raw >> jiffies_64 here. jiffies is a good candidate but it has wraparound overflow >> issue. >> Other time source are expensive here. >> >> Should I limit the code only running on 64bit kernel? > > Yes making it 64bit only should be fine. >
> Other alternative would be to use 32bit jiffies on 32bit. I assume > wrapping is not that big a problem here. > Thomas, is this acceptable? Thanks, -Aubrey
