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Linux kernel mirror (for testing)
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linux
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2#ifndef _ASM_POWERPC_PARAVIRT_H
3#define _ASM_POWERPC_PARAVIRT_H
4
5#include <linux/jump_label.h>
6#include <asm/smp.h>
7#ifdef CONFIG_PPC64
8#include <asm/paca.h>
9#include <asm/hvcall.h>
10#endif
11
12#ifdef CONFIG_PPC_SPLPAR
13DECLARE_STATIC_KEY_FALSE(shared_processor);
14
15static inline bool is_shared_processor(void)
16{
17 return static_branch_unlikely(&shared_processor);
18}
19
20/* If bit 0 is set, the cpu has been preempted */
21static inline u32 yield_count_of(int cpu)
22{
23 __be32 yield_count = READ_ONCE(lppaca_of(cpu).yield_count);
24 return be32_to_cpu(yield_count);
25}
26
27static inline void yield_to_preempted(int cpu, u32 yield_count)
28{
29 plpar_hcall_norets(H_CONFER, get_hard_smp_processor_id(cpu), yield_count);
30}
31
32static inline void prod_cpu(int cpu)
33{
34 plpar_hcall_norets(H_PROD, get_hard_smp_processor_id(cpu));
35}
36
37static inline void yield_to_any(void)
38{
39 plpar_hcall_norets(H_CONFER, -1, 0);
40}
41#else
42static inline bool is_shared_processor(void)
43{
44 return false;
45}
46
47static inline u32 yield_count_of(int cpu)
48{
49 return 0;
50}
51
52extern void ___bad_yield_to_preempted(void);
53static inline void yield_to_preempted(int cpu, u32 yield_count)
54{
55 ___bad_yield_to_preempted(); /* This would be a bug */
56}
57
58extern void ___bad_yield_to_any(void);
59static inline void yield_to_any(void)
60{
61 ___bad_yield_to_any(); /* This would be a bug */
62}
63
64extern void ___bad_prod_cpu(void);
65static inline void prod_cpu(int cpu)
66{
67 ___bad_prod_cpu(); /* This would be a bug */
68}
69
70#endif
71
72#define vcpu_is_preempted vcpu_is_preempted
73static inline bool vcpu_is_preempted(int cpu)
74{
75 if (!is_shared_processor())
76 return false;
77 if (yield_count_of(cpu) & 1)
78 return true;
79 return false;
80}
81
82static inline bool pv_is_native_spin_unlock(void)
83{
84 return !is_shared_processor();
85}
86
87#endif /* _ASM_POWERPC_PARAVIRT_H */