1#ifndef _ASM_POWERPC_CPUTHREADS_H
2#define _ASM_POWERPC_CPUTHREADS_H
3
4#include <linux/cpumask.h>
5
6/*
7 * Mapping of threads to cores
8 *
9 * Note: This implementation is limited to a power of 2 number of
10 * threads per core and the same number for each core in the system
11 * (though it would work if some processors had less threads as long
12 * as the CPU numbers are still allocated, just not brought online).
13 *
14 * However, the API allows for a different implementation in the future
15 * if needed, as long as you only use the functions and not the variables
16 * directly.
17 */
18
19#ifdef CONFIG_SMP
20extern int threads_per_core;
21extern int threads_per_subcore;
22extern int threads_shift;
23extern cpumask_t threads_core_mask;
24#else
25#define threads_per_core	1
26#define threads_per_subcore	1
27#define threads_shift		0
28#define threads_core_mask	(*get_cpu_mask(0))
29#endif
30
31/* cpu_thread_mask_to_cores - Return a cpumask of one per cores
32 *                            hit by the argument
33 *
34 * @threads:	a cpumask of threads
35 *
36 * This function returns a cpumask which will have one "cpu" (or thread)
37 * bit set for each core that has at least one thread set in the argument.
38 *
39 * This can typically be used for things like IPI for tlb invalidations
40 * since those need to be done only once per core/TLB
41 */
42static inline cpumask_t cpu_thread_mask_to_cores(const struct cpumask *threads)
43{
44	cpumask_t	tmp, res;
45	int		i;
46
47	cpumask_clear(&res);
48	for (i = 0; i < NR_CPUS; i += threads_per_core) {
49		cpumask_shift_left(&tmp, &threads_core_mask, i);
50		if (cpumask_intersects(threads, &tmp))
51			cpumask_set_cpu(i, &res);
52	}
53	return res;
54}
55
56static inline int cpu_nr_cores(void)
57{
58	return nr_cpu_ids >> threads_shift;
59}
60
61static inline cpumask_t cpu_online_cores_map(void)
62{
63	return cpu_thread_mask_to_cores(cpu_online_mask);
64}
65
66#ifdef CONFIG_SMP
67int cpu_core_index_of_thread(int cpu);
68int cpu_first_thread_of_core(int core);
69#else
70static inline int cpu_core_index_of_thread(int cpu) { return cpu; }
71static inline int cpu_first_thread_of_core(int core) { return core; }
72#endif
73
74static inline int cpu_thread_in_core(int cpu)
75{
76	return cpu & (threads_per_core - 1);
77}
78
79static inline int cpu_thread_in_subcore(int cpu)
80{
81	return cpu & (threads_per_subcore - 1);
82}
83
84static inline int cpu_first_thread_sibling(int cpu)
85{
86	return cpu & ~(threads_per_core - 1);
87}
88
89static inline int cpu_last_thread_sibling(int cpu)
90{
91	return cpu | (threads_per_core - 1);
92}
93
94
95
96#endif /* _ASM_POWERPC_CPUTHREADS_H */
97
98