metag: define __smp_xxx

This defines __smp_xxx barriers for metag,
for use by virtualization.

smp_xxx barriers are removed as they are
defined correctly by asm-generic/barriers.h

Note: as __smp_XX macros should not depend on CONFIG_SMP, they can not
use the existing fence() macro since that is defined differently between
SMP and !SMP.  For this reason, this patch introduces a wrapper
metag_fence() that doesn't depend on CONFIG_SMP.
fence() is then defined using that, depending on CONFIG_SMP.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
This commit is contained in:
Michael S. Tsirkin 2015-12-27 15:04:42 +02:00
parent eebd1b9278
commit afc22de0c0

View File

@ -44,13 +44,6 @@ static inline void wr_fence(void)
#define rmb() barrier()
#define wmb() mb()
#ifndef CONFIG_SMP
#define fence() do { } while (0)
#define smp_mb() barrier()
#define smp_rmb() barrier()
#define smp_wmb() barrier()
#else
#ifdef CONFIG_METAG_SMP_WRITE_REORDERING
/*
* Write to the atomic memory unlock system event register (command 0). This is
@ -60,26 +53,31 @@ static inline void wr_fence(void)
* incoherence). It is therefore ineffective if used after and on the same
* thread as a write.
*/
static inline void fence(void)
static inline void metag_fence(void)
{
volatile int *flushptr = (volatile int *) LINSYSEVENT_WR_ATOMIC_UNLOCK;
barrier();
*flushptr = 0;
barrier();
}
#define smp_mb() fence()
#define smp_rmb() fence()
#define smp_wmb() barrier()
#define __smp_mb() metag_fence()
#define __smp_rmb() metag_fence()
#define __smp_wmb() barrier()
#else
#define fence() do { } while (0)
#define smp_mb() barrier()
#define smp_rmb() barrier()
#define smp_wmb() barrier()
#endif
#define metag_fence() do { } while (0)
#define __smp_mb() barrier()
#define __smp_rmb() barrier()
#define __smp_wmb() barrier()
#endif
#define smp_mb__before_atomic() barrier()
#define smp_mb__after_atomic() barrier()
#ifdef CONFIG_SMP
#define fence() metag_fence()
#else
#define fence() do { } while (0)
#endif
#define __smp_mb__before_atomic() barrier()
#define __smp_mb__after_atomic() barrier()
#include <asm-generic/barrier.h>