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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 online threads
35 *
36 * This function returns a cpumask which will have one online cpu's
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, cpu;
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 cpu = cpumask_next_and(-1, &tmp, cpu_online_mask);
52 if (cpu < nr_cpu_ids)
53 cpumask_set_cpu(cpu, &res);
54 }
55 }
56 return res;
57}
58
59static inline int cpu_nr_cores(void)
60{
61 return nr_cpu_ids >> threads_shift;
62}
63
64static inline cpumask_t cpu_online_cores_map(void)
65{
66 return cpu_thread_mask_to_cores(cpu_online_mask);
67}
68
69#ifdef CONFIG_SMP
70int cpu_core_index_of_thread(int cpu);
71int cpu_first_thread_of_core(int core);
72#else
73static inline int cpu_core_index_of_thread(int cpu) { return cpu; }
74static inline int cpu_first_thread_of_core(int core) { return core; }
75#endif
76
77static inline int cpu_thread_in_core(int cpu)
78{
79 return cpu & (threads_per_core - 1);
80}
81
82static inline int cpu_thread_in_subcore(int cpu)
83{
84 return cpu & (threads_per_subcore - 1);
85}
86
87static inline int cpu_first_thread_sibling(int cpu)
88{
89 return cpu & ~(threads_per_core - 1);
90}
91
92static inline int cpu_last_thread_sibling(int cpu)
93{
94 return cpu | (threads_per_core - 1);
95}
96
97
98
99#endif /* _ASM_POWERPC_CPUTHREADS_H */
100