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
|
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Traceprobe fetch helper inlines
*/
static nokprobe_inline void
fetch_store_raw(unsigned long val, struct fetch_insn *code, void *buf)
{
switch (code->size) {
case 1:
*(u8 *)buf = (u8)val;
break;
case 2:
*(u16 *)buf = (u16)val;
break;
case 4:
*(u32 *)buf = (u32)val;
break;
case 8:
//TBD: 32bit signed
*(u64 *)buf = (u64)val;
break;
default:
*(unsigned long *)buf = val;
}
}
static nokprobe_inline void
fetch_apply_bitfield(struct fetch_insn *code, void *buf)
{
switch (code->basesize) {
case 1:
*(u8 *)buf <<= code->lshift;
*(u8 *)buf >>= code->rshift;
break;
case 2:
*(u16 *)buf <<= code->lshift;
*(u16 *)buf >>= code->rshift;
break;
case 4:
*(u32 *)buf <<= code->lshift;
*(u32 *)buf >>= code->rshift;
break;
case 8:
*(u64 *)buf <<= code->lshift;
*(u64 *)buf >>= code->rshift;
break;
}
}
/* Define this for each callsite */
static int
process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs,
void *dest, bool pre);
/* Sum up total data length for dynamic arraies (strings) */
static nokprobe_inline int
__get_data_size(struct trace_probe *tp, struct pt_regs *regs)
{
struct probe_arg *arg;
int i, ret = 0;
u32 len;
for (i = 0; i < tp->nr_args; i++) {
arg = tp->args + i;
if (unlikely(arg->dynamic)) {
process_fetch_insn(arg->code, regs, &len, true);
ret += len;
}
}
return ret;
}
/* Store the value of each argument */
static nokprobe_inline void
store_trace_args(int ent_size, struct trace_probe *tp, struct pt_regs *regs,
u8 *data, int maxlen)
{
struct probe_arg *arg;
u32 end = tp->size;
u32 *dl; /* Data (relative) location */
int i;
for (i = 0; i < tp->nr_args; i++) {
arg = tp->args + i;
if (unlikely(arg->dynamic)) {
/*
* First, we set the relative location and
* maximum data length to *dl
*/
dl = (u32 *)(data + arg->offset);
*dl = make_data_rloc(maxlen, end - arg->offset);
/* Then try to fetch string or dynamic array data */
process_fetch_insn(arg->code, regs, dl, false);
/* Reduce maximum length */
end += get_rloc_len(*dl);
maxlen -= get_rloc_len(*dl);
/* Trick here, convert data_rloc to data_loc */
*dl = convert_rloc_to_loc(*dl, ent_size + arg->offset);
} else
/* Just fetching data normally */
process_fetch_insn(arg->code, regs, data + arg->offset,
false);
}
}
static inline int
print_probe_args(struct trace_seq *s, struct probe_arg *args, int nr_args,
u8 *data, void *field)
{
int i;
for (i = 0; i < nr_args; i++) {
trace_seq_printf(s, " %s=", args[i].name);
if (!args[i].type->print(s, data + args[i].offset, field))
return -ENOMEM;
}
return 0;
}
|
