On Thursday 05 April 2007 23:00:22 Jeremy Fitzhardinge wrote: > Andi Kleen wrote: > > The interrupts can only happen when the other CPU is already lazy > > and enter_lazy_tlb would be a nop then. The flushers itself are > > synchronized by the page_table_lock or the mm semaphore. > > > > Against switch_mm it tries to protect with ordering. > > > > wmb()s are not needed on x86 (ok minus errata on ppro and > > VIA magic mode but which is UP only). That would leave some rmb()s, > > but I don't see any place they would be needed. > > > > Hm, I was more wondering about simple compiler reordering. Does the > relative order of setting and reading cpu_tlbstate.state, active_mm and > the mm->cpu_vm_mask matter?
Hmm, perhaps a barrier between state and active_mm might be a good idea. Setting active_mm after state might be problematic. cpu_vm_mask should be already a memory barrier. -Andi - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/