在 2009-05-20三的 08:07 +0100，Ralf Baechle写道： > On Wed, May 20, 2009 at 10:28:14AM +0800, yanh wrote: > > > I have test this patch just now. It works well on yeeloong. > > Thanks for testing. > > > I have one question what's the difference between the two patch? > > Uncached writes can't be re-ordered. By adding a read after the last > write my patch forces not only completion of the preceding write but due > to this ordering constraint also completion of all preceding writes is > enforced. > > I/O space writes are slow. I mean slower than slugs in space. So my > patch is an optimization but that was not the point; I really only meant > to verify that we understood what's going on and we seem to. Now let's > fix the real issue and make outX() non-posted. Thanks for your explanation. > > Ralf >
