[RFC v2 11/13] rust: sync: Add memory barriers

[Boqun Feng]

On Fri, Nov 01, 2024 at 02:55:23PM +0800, David Gow wrote:
> On Fri, 1 Nov 2024 at 14:07, Boqun Feng <boqun.feng at gmail.com> wrote:
> >
> > Memory barriers are building blocks for concurrent code, hence provide
> > a minimal set of them.
> >
> > The compiler barrier, barrier(), is implemented in inline asm instead of
> > using core::sync::atomic::compiler_fence() because memory models are
> > different: kernel's atomics are implemented in inline asm therefore the
> > compiler barrier should be implemented in inline asm as well.
> >
> > Signed-off-by: Boqun Feng <boqun.feng at gmail.com>
> > ---
> >  rust/helpers/helpers.c      |  1 +
> >  rust/kernel/sync.rs         |  1 +
> >  rust/kernel/sync/barrier.rs | 67 +++++++++++++++++++++++++++++++++++++
> >  3 files changed, 69 insertions(+)
> >  create mode 100644 rust/kernel/sync/barrier.rs
> >
> > diff --git a/rust/helpers/helpers.c b/rust/helpers/helpers.c
> > index ab5a3f1be241..f4a94833b29d 100644
> > --- a/rust/helpers/helpers.c
> > +++ b/rust/helpers/helpers.c
> > @@ -8,6 +8,7 @@
> >   */
> >
> >  #include "atomic.c"
> > +#include "barrier.c"
> 
> It looks like "barrier.c" is missing, so this isn't compiling for me.
> I assume it was meant to be added in this patch...?
> 

Yes, I just send an updated one.

Glad being "checking missing files" buddies with you ;-) Thanks!

Regards,
Boqun

> Thanks,
> -- David