Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit e54d2f61 authored by Stefano Stabellini's avatar Stefano Stabellini
Browse files

xen/arm: sync_bitops 



sync_bitops functions are equivalent to the SMP implementation of the
original functions, independently from CONFIG_SMP being defined.

We need them because _set_bit etc are not SMP safe if !CONFIG_SMP. But
under Xen you might be communicating with a completely external entity
who might be on another CPU (e.g. two uniprocessor guests communicating
via event channels and grant tables). So we need a variant of the bit
ops which are SMP safe even on a UP kernel.

Signed-off-by: default avatarStefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
parent 36a67abc

arch/arm/include/asm/sync_bitops.h

0 → 100644
+27 −0
Original line number Diff line number Diff line 
#ifndef __ASM_SYNC_BITOPS_H__

#define __ASM_SYNC_BITOPS_H__



#include <asm/bitops.h>

#include <asm/system.h>



/* sync_bitops functions are equivalent to the SMP implementation of the

 * original functions, independently from CONFIG_SMP being defined.

 *

 * We need them because _set_bit etc are not SMP safe if !CONFIG_SMP. But

 * under Xen you might be communicating with a completely external entity

 * who might be on another CPU (e.g. two uniprocessor guests communicating

 * via event channels and grant tables). So we need a variant of the bit

 * ops which are SMP safe even on a UP kernel.

 */



#define sync_set_bit(nr, p)		_set_bit(nr, p)

#define sync_clear_bit(nr, p)		_clear_bit(nr, p)

#define sync_change_bit(nr, p)		_change_bit(nr, p)

#define sync_test_and_set_bit(nr, p)	_test_and_set_bit(nr, p)

#define sync_test_and_clear_bit(nr, p)	_test_and_clear_bit(nr, p)

#define sync_test_and_change_bit(nr, p)	_test_and_change_bit(nr, p)

#define sync_test_bit(nr, addr)		test_bit(nr, addr)

#define sync_cmpxchg			cmpxchg





#endif