> On Jun 25, 2019, at 8:00 PM, Dave Hansen <dave.hansen@xxxxxxxxx> wrote: > > On 6/25/19 7:35 PM, Nadav Amit wrote: >>>> const struct flush_tlb_info *f = info; >>>> + enum tlb_flush_reason reason; >>>> + >>>> + reason = (f->mm == NULL) ? TLB_LOCAL_SHOOTDOWN : TLB_LOCAL_MM_SHOOTDOWN; >>> >>> Should we just add the "reason" to flush_tlb_info? It's OK-ish to imply >>> it like this, but seems like it would be nicer and easier to track down >>> the origins of these things if we did this at the caller. >> >> I prefer not to. I want later to inline flush_tlb_info into the same >> cacheline that holds call_function_data. Increasing the size of >> flush_tlb_info for no good reason will not help… > > Well, flush_tlb_info is at 6/8ths of a cacheline at the moment. > call_function_data is 3/8ths. To me, that means we have some slack in > the size. I do not understand your math.. :( 6 + 3 > 8 so putting both flush_tlb_info and call_function_data does not leave us any slack (we can save one qword, so we can actually put them at the same cacheline). You can see my current implementation here: https://lore.kernel.org/lkml/20190531063645.4697-4-namit@xxxxxxxxxx/T/#m0ab5fe0799ba9ff0d41197f1095679fe26aebd57 https://lore.kernel.org/lkml/20190531063645.4697-4-namit@xxxxxxxxxx/T/#m7b35a93dffd23fbb7ca813c795a0777d4cdcb51b
