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
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
|
/*
* ring buffer based C-state tracer
*
* Arjan van de Ven <arjan@linux.intel.com>
* Copyright (C) 2008 Intel Corporation
*
* Much is borrowed from trace_boot.c which is
* Copyright (C) 2008 Frederic Weisbecker <fweisbec@gmail.com>
*
*/
#include <linux/init.h>
#include <linux/debugfs.h>
#include <trace/power.h>
#include <linux/kallsyms.h>
#include <linux/module.h>
#include "trace.h"
#include "trace_output.h"
static struct trace_array *power_trace;
static int __read_mostly trace_power_enabled;
static void probe_power_start(struct power_trace *it, unsigned int type,
unsigned int level)
{
if (!trace_power_enabled)
return;
memset(it, 0, sizeof(struct power_trace));
it->state = level;
it->type = type;
it->stamp = ktime_get();
}
static void probe_power_end(struct power_trace *it)
{
struct ftrace_event_call *call = &event_power;
struct ring_buffer_event *event;
struct ring_buffer *buffer;
struct trace_power *entry;
struct trace_array_cpu *data;
struct trace_array *tr = power_trace;
if (!trace_power_enabled)
return;
buffer = tr->buffer;
preempt_disable();
it->end = ktime_get();
data = tr->data[smp_processor_id()];
event = trace_buffer_lock_reserve(buffer, TRACE_POWER,
sizeof(*entry), 0, 0);
if (!event)
goto out;
entry = ring_buffer_event_data(event);
entry->state_data = *it;
if (!filter_check_discard(call, entry, buffer, event))
trace_buffer_unlock_commit(buffer, event, 0, 0);
out:
preempt_enable();
}
static void probe_power_mark(struct power_trace *it, unsigned int type,
unsigned int level)
{
struct ftrace_event_call *call = &event_power;
struct ring_buffer_event *event;
struct ring_buffer *buffer;
struct trace_power *entry;
struct trace_array_cpu *data;
struct trace_array *tr = power_trace;
if (!trace_power_enabled)
return;
buffer = tr->buffer;
memset(it, 0, sizeof(struct power_trace));
it->state = level;
it->type = type;
it->stamp = ktime_get();
preempt_disable();
it->end = it->stamp;
data = tr->data[smp_processor_id()];
event = trace_buffer_lock_reserve(buffer, TRACE_POWER,
sizeof(*entry), 0, 0);
if (!event)
goto out;
entry = ring_buffer_event_data(event);
entry->state_data = *it;
if (!filter_check_discard(call, entry, buffer, event))
trace_buffer_unlock_commit(buffer, event, 0, 0);
out:
preempt_enable();
}
static int tracing_power_register(void)
{
int ret;
ret = register_trace_power_start(probe_power_start);
if (ret) {
pr_info("power trace: Couldn't activate tracepoint"
" probe to trace_power_start\n");
return ret;
}
ret = register_trace_power_end(probe_power_end);
if (ret) {
pr_info("power trace: Couldn't activate tracepoint"
" probe to trace_power_end\n");
goto fail_start;
}
ret = register_trace_power_mark(probe_power_mark);
if (ret) {
pr_info("power trace: Couldn't activate tracepoint"
" probe to trace_power_mark\n");
goto fail_end;
}
return ret;
fail_end:
unregister_trace_power_end(probe_power_end);
fail_start:
unregister_trace_power_start(probe_power_start);
return ret;
}
static void start_power_trace(struct trace_array *tr)
{
trace_power_enabled = 1;
}
static void stop_power_trace(struct trace_array *tr)
{
trace_power_enabled = 0;
}
static void power_trace_reset(struct trace_array *tr)
{
trace_power_enabled = 0;
unregister_trace_power_start(probe_power_start);
unregister_trace_power_end(probe_power_end);
unregister_trace_power_mark(probe_power_mark);
}
static int power_trace_init(struct trace_array *tr)
{
power_trace = tr;
trace_power_enabled = 1;
tracing_power_register();
tracing_reset_online_cpus(tr);
return 0;
}
static enum print_line_t power_print_line(struct trace_iterator *iter)
{
int ret = 0;
struct trace_entry *entry = iter->ent;
struct trace_power *field ;
struct power_trace *it;
struct trace_seq *s = &iter->seq;
struct timespec stamp;
struct timespec duration;
trace_assign_type(field, entry);
it = &field->state_data;
stamp = ktime_to_timespec(it->stamp);
duration = ktime_to_timespec(ktime_sub(it->end, it->stamp));
if (entry->type == TRACE_POWER) {
if (it->type == POWER_CSTATE)
ret = trace_seq_printf(s, "[%5ld.%09ld] CSTATE: Going to C%i on cpu %i for %ld.%09ld\n",
stamp.tv_sec,
stamp.tv_nsec,
it->state, iter->cpu,
duration.tv_sec,
duration.tv_nsec);
if (it->type == POWER_PSTATE)
ret = trace_seq_printf(s, "[%5ld.%09ld] PSTATE: Going to P%i on cpu %i\n",
stamp.tv_sec,
stamp.tv_nsec,
it->state, iter->cpu);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
return TRACE_TYPE_HANDLED;
}
return TRACE_TYPE_UNHANDLED;
}
static void power_print_header(struct seq_file *s)
{
seq_puts(s, "# TIMESTAMP STATE EVENT\n");
seq_puts(s, "# | | |\n");
}
static struct tracer power_tracer __read_mostly =
{
.name = "power",
.init = power_trace_init,
.start = start_power_trace,
.stop = stop_power_trace,
.reset = power_trace_reset,
.print_line = power_print_line,
.print_header = power_print_header,
};
static int init_power_trace(void)
{
return register_tracer(&power_tracer);
}
device_initcall(init_power_trace);
|
