* Shaohua Li <shaohua.li@xxxxxxxxx> wrote: > On Tue, 2011-12-06 at 07:26 +0800, Linus Torvalds wrote: > > On Mon, Dec 5, 2011 at 9:56 AM, tip-bot for Shaohua Li > > <shaohua.li@xxxxxxxxx> wrote: > > > > > > x86/mm: Avoid superflous leave_mm() in the TLB flush path > > > > > > If just one page VA tlb is required to be flushed and current > > > task is in lazy TLB state, doing leave_mm() is superfluous > > > because it flushes the whole TLB. This can reduce some TLB > > > miss. > > > > Are you sure this is a good idea? > > > > We may be *much* better off leaving the VM and avoiding future IPI's > > than trying to flush pages one by one over and over again. > > > > IPI's are expensive. > > > > I don't think you thought this through, and if you *did* think it > > through and actually have numbers that it's cheaper to stay with the > > MM, I think you need to show those numbers. > > good point, I didn't think of it. It's unlikely we just flush > one tlb page. please drop the patch. Dropped, thanks guys. Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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