On Thu, Feb 11, 2016 at 12:33:30AM +0100, Alfredo Alvarez Fernandez wrote: > From: Alfredo Alvarez Fernandez <[email protected]> > > This was added to the kernel code in 1658d35ead5d ("list: Use > READ_ONCE() when testing for empty lists") > There's nothing special we need to do about it in userspace. > > Signed-off-by: Alfredo Alvarez Fernandez <[email protected]> > --- > tools/lib/lockdep/uinclude/linux/compiler.h | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/tools/lib/lockdep/uinclude/linux/compiler.h > b/tools/lib/lockdep/uinclude/linux/compiler.h > index 6386dc3..fd3e56a 100644 > --- a/tools/lib/lockdep/uinclude/linux/compiler.h > +++ b/tools/lib/lockdep/uinclude/linux/compiler.h > @@ -3,6 +3,7 @@ > > #define __used __attribute__((__unused__)) > #define unlikely > +#define READ_ONCE(x) (x) > #define WRITE_ONCE(x, val) x=(val)
I would argue we'd still very much want the volatile cast for both READ and WRITE_ONCE(). Why do these things have different semantics between user and kernel space?
