| Message ID | 20160531094844.342792251@infradead.org |
|---|---|
| State | Awaiting Upstream |
| Delegated to: | Pablo Neira |
| Headers | show |
On 5/31/2016 5:41 AM, Peter Zijlstra wrote: > Since TILE doesn't do read speculation, its control dependencies also > guarantee LOAD->LOAD order and we don't need the additional RMB > otherwise required to provide ACQUIRE semantics. > > Cc: Chris Metcalf<cmetcalf@mellanox.com> > Signed-off-by: Peter Zijlstra (Intel)<peterz@infradead.org> > --- > arch/tile/include/asm/barrier.h | 7 +++++++ > 1 file changed, 7 insertions(+) Looks good. Acked-by: Chris Metcalf <cmetcalf@mellanox.com>
--- a/arch/tile/include/asm/barrier.h +++ b/arch/tile/include/asm/barrier.h @@ -87,6 +87,13 @@ mb_incoherent(void) #define __smp_mb__after_atomic() __smp_mb() #endif +/* + * The TILE architecture does not do speculative reads; this ensures + * that a control dependency also orders against loads and already provides + * a LOAD->{LOAD,STORE} order and can forgo the additional RMB. + */ +#define smp_acquire__after_ctrl_dep() barrier() + #include <asm-generic/barrier.h> #endif /* !__ASSEMBLY__ */
Since TILE doesn't do read speculation, its control dependencies also guarantee LOAD->LOAD order and we don't need the additional RMB otherwise required to provide ACQUIRE semantics. Cc: Chris Metcalf <cmetcalf@mellanox.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> --- arch/tile/include/asm/barrier.h | 7 +++++++ 1 file changed, 7 insertions(+) -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html