On Sun, 27 Nov 2022 19:43:47 -0800, Davidlohr Bueso <[email protected]> wrote: > This gets rid of the last references to smp_read_barrier_depends() > which for the kernel side was removed in v5.9. The serialization > required for Alpha is done inside READ_ONCE() instead of having > users deal with it. Simply use a full barrier, the architecture > does not have rmb in the first place. > > Signed-off-by: Davidlohr Bueso <[email protected]>
Reviewed-by: Xuan Zhuo <[email protected]> > --- > tools/virtio/ringtest/main.h | 17 ++++++++++------- > 1 file changed, 10 insertions(+), 7 deletions(-) > > diff --git a/tools/virtio/ringtest/main.h b/tools/virtio/ringtest/main.h > index 9ed09caa659e..b68920d52750 100644 > --- a/tools/virtio/ringtest/main.h > +++ b/tools/virtio/ringtest/main.h > @@ -140,12 +140,6 @@ static inline void busy_wait(void) > #define smp_wmb() smp_release() > #endif > > -#ifdef __alpha__ > -#define smp_read_barrier_depends() smp_acquire() > -#else > -#define smp_read_barrier_depends() do {} while(0) > -#endif > - > static __always_inline > void __read_once_size(const volatile void *p, void *res, int size) > { > @@ -175,13 +169,22 @@ static __always_inline void __write_once_size(volatile > void *p, void *res, int s > } > } > > +#ifdef __alpha__ > #define READ_ONCE(x) \ > ({ \ > union { typeof(x) __val; char __c[1]; } __u; \ > __read_once_size(&(x), __u.__c, sizeof(x)); \ > - smp_read_barrier_depends(); /* Enforce dependency ordering from x */ \ > + smp_mb(); /* Enforce dependency ordering from x */ \ > __u.__val; \ > }) > +#else > +#define READ_ONCE(x) \ > +({ \ > + union { typeof(x) __val; char __c[1]; } __u; \ > + __read_once_size(&(x), __u.__c, sizeof(x)); \ > + __u.__val; \ > +}) > +#endif > > #define WRITE_ONCE(x, val) \ > ({ \ > -- > 2.38.1 > > _______________________________________________ > Virtualization mailing list > [email protected] > https://lists.linuxfoundation.org/mailman/listinfo/virtualization _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
