xref: /OK3568_Linux_fs/kernel/include/asm-generic/bitops/sched.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun #ifndef _ASM_GENERIC_BITOPS_SCHED_H_
3*4882a593Smuzhiyun #define _ASM_GENERIC_BITOPS_SCHED_H_
4*4882a593Smuzhiyun 
5*4882a593Smuzhiyun #include <linux/compiler.h>	/* unlikely() */
6*4882a593Smuzhiyun #include <asm/types.h>
7*4882a593Smuzhiyun 
8*4882a593Smuzhiyun /*
9*4882a593Smuzhiyun  * Every architecture must define this function. It's the fastest
10*4882a593Smuzhiyun  * way of searching a 100-bit bitmap.  It's guaranteed that at least
11*4882a593Smuzhiyun  * one of the 100 bits is cleared.
12*4882a593Smuzhiyun  */
sched_find_first_bit(const unsigned long * b)13*4882a593Smuzhiyun static inline int sched_find_first_bit(const unsigned long *b)
14*4882a593Smuzhiyun {
15*4882a593Smuzhiyun #if BITS_PER_LONG == 64
16*4882a593Smuzhiyun 	if (b[0])
17*4882a593Smuzhiyun 		return __ffs(b[0]);
18*4882a593Smuzhiyun 	return __ffs(b[1]) + 64;
19*4882a593Smuzhiyun #elif BITS_PER_LONG == 32
20*4882a593Smuzhiyun 	if (b[0])
21*4882a593Smuzhiyun 		return __ffs(b[0]);
22*4882a593Smuzhiyun 	if (b[1])
23*4882a593Smuzhiyun 		return __ffs(b[1]) + 32;
24*4882a593Smuzhiyun 	if (b[2])
25*4882a593Smuzhiyun 		return __ffs(b[2]) + 64;
26*4882a593Smuzhiyun 	return __ffs(b[3]) + 96;
27*4882a593Smuzhiyun #else
28*4882a593Smuzhiyun #error BITS_PER_LONG not defined
29*4882a593Smuzhiyun #endif
30*4882a593Smuzhiyun }
31*4882a593Smuzhiyun 
32*4882a593Smuzhiyun #endif /* _ASM_GENERIC_BITOPS_SCHED_H_ */
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