On Wed, Mar 06, 2013 at 03:54:42PM +1100, Rusty Russell wrote: > In the coming vringh_test, we share an mmap with another userspace process > for testing. This requires real barriers. > > Signed-off-by: Rusty Russell <ru...@rustcorp.com.au> > > diff --git a/tools/virtio/asm/barrier.h b/tools/virtio/asm/barrier.h > index aff61e1..7a63693 100644 > --- a/tools/virtio/asm/barrier.h > +++ b/tools/virtio/asm/barrier.h > @@ -3,8 +3,8 @@ > #define mb() __sync_synchronize() > > #define smp_mb() mb() > -# define smp_rmb() barrier() > -# define smp_wmb() barrier() > +# define smp_rmb() mb() > +# define smp_wmb() mb() > /* Weak barriers should be used. If not - it's a bug */ > # define rmb() abort() > # define wmb() abort()
Hmm this seems wrong on x86 which has strong order in hardware. It should not matter whether the other side is a userspace process or a kernel thread. -- MST _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization
