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15#include <linux/kernel.h>
16#include <linux/spinlock.h>
17#include <linux/module.h>
18#include <linux/stringify.h>
19#include <linux/smp.h>
20
21
22#if defined(CONFIG_PPC_SPLPAR) || defined(CONFIG_PPC_ISERIES)
23#include <asm/hvcall.h>
24#include <asm/iseries/hv_call.h>
25#include <asm/smp.h>
26#include <asm/firmware.h>
27
28void __spin_yield(raw_spinlock_t *lock)
29{
30 unsigned int lock_value, holder_cpu, yield_count;
31
32 lock_value = lock->slock;
33 if (lock_value == 0)
34 return;
35 holder_cpu = lock_value & 0xffff;
36 BUG_ON(holder_cpu >= NR_CPUS);
37 yield_count = lppaca[holder_cpu].yield_count;
38 if ((yield_count & 1) == 0)
39 return;
40 rmb();
41 if (lock->slock != lock_value)
42 return;
43 if (firmware_has_feature(FW_FEATURE_ISERIES))
44 HvCall2(HvCallBaseYieldProcessor, HvCall_YieldToProc,
45 ((u64)holder_cpu << 32) | yield_count);
46#ifdef CONFIG_PPC_SPLPAR
47 else
48 plpar_hcall_norets(H_CONFER,
49 get_hard_smp_processor_id(holder_cpu), yield_count);
50#endif
51}
52
53
54
55
56
57
58void __rw_yield(raw_rwlock_t *rw)
59{
60 int lock_value;
61 unsigned int holder_cpu, yield_count;
62
63 lock_value = rw->lock;
64 if (lock_value >= 0)
65 return;
66 holder_cpu = lock_value & 0xffff;
67 BUG_ON(holder_cpu >= NR_CPUS);
68 yield_count = lppaca[holder_cpu].yield_count;
69 if ((yield_count & 1) == 0)
70 return;
71 rmb();
72 if (rw->lock != lock_value)
73 return;
74 if (firmware_has_feature(FW_FEATURE_ISERIES))
75 HvCall2(HvCallBaseYieldProcessor, HvCall_YieldToProc,
76 ((u64)holder_cpu << 32) | yield_count);
77#ifdef CONFIG_PPC_SPLPAR
78 else
79 plpar_hcall_norets(H_CONFER,
80 get_hard_smp_processor_id(holder_cpu), yield_count);
81#endif
82}
83#endif
84
85void __raw_spin_unlock_wait(raw_spinlock_t *lock)
86{
87 while (lock->slock) {
88 HMT_low();
89 if (SHARED_PROCESSOR)
90 __spin_yield(lock);
91 }
92 HMT_medium();
93}
94
95EXPORT_SYMBOL(__raw_spin_unlock_wait);
96