On Fri, May 04, 2007 at 05:13:09PM -0500, Linas Vepstas wrote: > On Wed, May 02, 2007 at 03:40:20PM -0500, Scott Wood wrote: > > > > Well, Segher doesn't want me to use iobarrier (because it's not I/O). > > Andy doesn't want me to use wmb() (because it's sync). I don't think > > something like gfar_wmb() would be appropriate. So the remaining > > options are either eieio(), > > ? Just curious... the original intent of eieio was to order I/O, > such as MMIO; it has no effect on memory that isn't marked > cache-inhibited or write-trhough or guarded. Has this changed? > I guess I haven't kept up with the times ... is eieio now > being used to provide some other kind of barrier? > Is eieio providing some sort of SMP synchronization side-effect? > > Point being: if Segher doesn't let you "use iobarrier (because > it's not I/O)", then I don't understand why eieio would work (since > that's for io only).
Eieio has always worked for regular cachable memory as well, it just never orders _between_ cache inhibited/guarded and cachable memory. Book II 2.03 has a pretty good description of it on page 367. -Olof - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
