1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
|
// SPDX-License-Identifier: GPL-2.0
#include <linux/export.h>
#include <linux/percpu.h>
#include <linux/preempt.h>
#include <asm/msr.h>
#define CREATE_TRACE_POINTS
#include <asm/msr-trace.h>
struct msr *msrs_alloc(void)
{
struct msr *msrs = NULL;
msrs = alloc_percpu(struct msr);
if (!msrs) {
pr_warn("%s: error allocating msrs\n", __func__);
return NULL;
}
return msrs;
}
EXPORT_SYMBOL(msrs_alloc);
void msrs_free(struct msr *msrs)
{
free_percpu(msrs);
}
EXPORT_SYMBOL(msrs_free);
/**
* Read an MSR with error handling
*
* @msr: MSR to read
* @m: value to read into
*
* It returns read data only on success, otherwise it doesn't change the output
* argument @m.
*
*/
int msr_read(u32 msr, struct msr *m)
{
int err;
u64 val;
err = rdmsrl_safe(msr, &val);
if (!err)
m->q = val;
return err;
}
/**
* Write an MSR with error handling
*
* @msr: MSR to write
* @m: value to write
*/
int msr_write(u32 msr, struct msr *m)
{
return wrmsrl_safe(msr, m->q);
}
static inline int __flip_bit(u32 msr, u8 bit, bool set)
{
struct msr m, m1;
int err = -EINVAL;
if (bit > 63)
return err;
err = msr_read(msr, &m);
if (err)
return err;
m1 = m;
if (set)
m1.q |= BIT_64(bit);
else
m1.q &= ~BIT_64(bit);
if (m1.q == m.q)
return 0;
err = msr_write(msr, &m1);
if (err)
return err;
return 1;
}
/**
* Set @bit in a MSR @msr.
*
* Retval:
* < 0: An error was encountered.
* = 0: Bit was already set.
* > 0: Hardware accepted the MSR write.
*/
int msr_set_bit(u32 msr, u8 bit)
{
return __flip_bit(msr, bit, true);
}
/**
* Clear @bit in a MSR @msr.
*
* Retval:
* < 0: An error was encountered.
* = 0: Bit was already cleared.
* > 0: Hardware accepted the MSR write.
*/
int msr_clear_bit(u32 msr, u8 bit)
{
return __flip_bit(msr, bit, false);
}
#ifdef CONFIG_TRACEPOINTS
void do_trace_write_msr(unsigned int msr, u64 val, int failed)
{
trace_write_msr(msr, val, failed);
}
EXPORT_SYMBOL(do_trace_write_msr);
EXPORT_TRACEPOINT_SYMBOL(write_msr);
void do_trace_read_msr(unsigned int msr, u64 val, int failed)
{
trace_read_msr(msr, val, failed);
}
EXPORT_SYMBOL(do_trace_read_msr);
EXPORT_TRACEPOINT_SYMBOL(read_msr);
void do_trace_rdpmc(unsigned counter, u64 val, int failed)
{
trace_rdpmc(counter, val, failed);
}
EXPORT_SYMBOL(do_trace_rdpmc);
EXPORT_TRACEPOINT_SYMBOL(rdpmc);
#endif
|
