On Sat, Nov 01, 2014 at 05:01:30PM +0000, Linus Torvalds wrote: > On Wed, Oct 29, 2014 at 2:27 PM, Benjamin Herrenschmidt > <b...@kernel.crashing.org> wrote: > > > > TLB flushing is only me I think, I'll engage my brain after breakfast > > and see if is all good > > Ping? Breakfast is either long over, of you're starting to look a bit > like Mr Creosote...
Wafer thin patch? > Anyway, Will, I assume this is not a correctness issue for you, just > an annoying performance issue. Right? Or is there actually some issue > with the actual range not being set to be sufficiently large? Yeah, it's just a performance issue. For ranges over 1k pages, we end up flushing the whole TLB. > Also, it strikes me that I *think* that you might be able to extend > your patch to remove the whole "need_flush" field, since as far as I > can tell, "tlb->need_flush" is now equivalent to "tlb->start < > tlb->end". Of course, as long as we still require that > "need_flush_all", that doesn't actually save us any space, so maybe > it's not worth changing. We use `tlb->end > 0' in the arm64 backend, so I think you're right. I'll take a look in the name of cleanup and this can wait until 3.19. Will -- 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/