On Thu, 2008-06-05 at 10:40 +0200, Jes Sorensen wrote: > Jesse Barnes wrote: > > Now, in hindsight, using a PIO write set & test flag approach in > > writeX/spin_unlock (ala powerpc) might have been a better approach, but > > iirc > > that never came up in the discussion, probably because we were focused on > > PCI > > posting and not uncached vs. cached ordering. > > Hi Jesse, > > I am going to take a stab at implementing this so we can see how much > of an impact it will have.
Note that the powerpc implementation currently clears the flag on spin_lock and tests it on unlock. We are considering changing that to not touch the flag on spin_lock and just clear it whenever we do a sync (ie, on unlock, on explicit mmiowb, and possibly even on readl's where we happen to do sync's). Ben. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
