xref: /OK3568_Linux_fs/kernel/arch/microblaze/include/asm/atomic.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun #ifndef _ASM_MICROBLAZE_ATOMIC_H
3*4882a593Smuzhiyun #define _ASM_MICROBLAZE_ATOMIC_H
4*4882a593Smuzhiyun 
5*4882a593Smuzhiyun #include <asm/cmpxchg.h>
6*4882a593Smuzhiyun #include <asm-generic/atomic.h>
7*4882a593Smuzhiyun #include <asm-generic/atomic64.h>
8*4882a593Smuzhiyun 
9*4882a593Smuzhiyun /*
10*4882a593Smuzhiyun  * Atomically test *v and decrement if it is greater than 0.
11*4882a593Smuzhiyun  * The function returns the old value of *v minus 1.
12*4882a593Smuzhiyun  */
atomic_dec_if_positive(atomic_t * v)13*4882a593Smuzhiyun static inline int atomic_dec_if_positive(atomic_t *v)
14*4882a593Smuzhiyun {
15*4882a593Smuzhiyun 	unsigned long flags;
16*4882a593Smuzhiyun 	int res;
17*4882a593Smuzhiyun 
18*4882a593Smuzhiyun 	local_irq_save(flags);
19*4882a593Smuzhiyun 	res = v->counter - 1;
20*4882a593Smuzhiyun 	if (res >= 0)
21*4882a593Smuzhiyun 		v->counter = res;
22*4882a593Smuzhiyun 	local_irq_restore(flags);
23*4882a593Smuzhiyun 
24*4882a593Smuzhiyun 	return res;
25*4882a593Smuzhiyun }
26*4882a593Smuzhiyun #define atomic_dec_if_positive atomic_dec_if_positive
27*4882a593Smuzhiyun 
28*4882a593Smuzhiyun #endif /* _ASM_MICROBLAZE_ATOMIC_H */
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