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1#include "evlist.h"
2#include "evsel.h"
3#include "cpumap.h"
4#include "parse-events.h"
5#include <api/fs/fs.h>
6#include "util.h"
7#include "cloexec.h"
8
9typedef void (*setup_probe_fn_t)(struct perf_evsel *evsel);
10
11static int perf_do_probe_api(setup_probe_fn_t fn, int cpu, const char *str)
12{
13 struct perf_evlist *evlist;
14 struct perf_evsel *evsel;
15 unsigned long flags = perf_event_open_cloexec_flag();
16 int err = -EAGAIN, fd;
17 static pid_t pid = -1;
18
19 evlist = perf_evlist__new();
20 if (!evlist)
21 return -ENOMEM;
22
23 if (parse_events(evlist, str, NULL))
24 goto out_delete;
25
26 evsel = perf_evlist__first(evlist);
27
28 while (1) {
29 fd = sys_perf_event_open(&evsel->attr, pid, cpu, -1, flags);
30 if (fd < 0) {
31 if (pid == -1 && errno == EACCES) {
32 pid = 0;
33 continue;
34 }
35 goto out_delete;
36 }
37 break;
38 }
39 close(fd);
40
41 fn(evsel);
42
43 fd = sys_perf_event_open(&evsel->attr, pid, cpu, -1, flags);
44 if (fd < 0) {
45 if (errno == EINVAL)
46 err = -EINVAL;
47 goto out_delete;
48 }
49 close(fd);
50 err = 0;
51
52out_delete:
53 perf_evlist__delete(evlist);
54 return err;
55}
56
57static bool perf_probe_api(setup_probe_fn_t fn)
58{
59 const char *try[] = {"cycles:u", "instructions:u", "cpu-clock:u", NULL};
60 struct cpu_map *cpus;
61 int cpu, ret, i = 0;
62
63 cpus = cpu_map__new(NULL);
64 if (!cpus)
65 return false;
66 cpu = cpus->map[0];
67 cpu_map__put(cpus);
68
69 do {
70 ret = perf_do_probe_api(fn, cpu, try[i++]);
71 if (!ret)
72 return true;
73 } while (ret == -EAGAIN && try[i]);
74
75 return false;
76}
77
78static void perf_probe_sample_identifier(struct perf_evsel *evsel)
79{
80 evsel->attr.sample_type |= PERF_SAMPLE_IDENTIFIER;
81}
82
83static void perf_probe_comm_exec(struct perf_evsel *evsel)
84{
85 evsel->attr.comm_exec = 1;
86}
87
88static void perf_probe_context_switch(struct perf_evsel *evsel)
89{
90 evsel->attr.context_switch = 1;
91}
92
93bool perf_can_sample_identifier(void)
94{
95 return perf_probe_api(perf_probe_sample_identifier);
96}
97
98static bool perf_can_comm_exec(void)
99{
100 return perf_probe_api(perf_probe_comm_exec);
101}
102
103bool perf_can_record_switch_events(void)
104{
105 return perf_probe_api(perf_probe_context_switch);
106}
107
108bool perf_can_record_cpu_wide(void)
109{
110 struct perf_event_attr attr = {
111 .type = PERF_TYPE_SOFTWARE,
112 .config = PERF_COUNT_SW_CPU_CLOCK,
113 .exclude_kernel = 1,
114 };
115 struct cpu_map *cpus;
116 int cpu, fd;
117
118 cpus = cpu_map__new(NULL);
119 if (!cpus)
120 return false;
121 cpu = cpus->map[0];
122 cpu_map__put(cpus);
123
124 fd = sys_perf_event_open(&attr, -1, cpu, -1, 0);
125 if (fd < 0)
126 return false;
127 close(fd);
128
129 return true;
130}
131
132void perf_evlist__config(struct perf_evlist *evlist, struct record_opts *opts)
133{
134 struct perf_evsel *evsel;
135 bool use_sample_identifier = false;
136 bool use_comm_exec;
137
138 /*
139 * Set the evsel leader links before we configure attributes,
140 * since some might depend on this info.
141 */
142 if (opts->group)
143 perf_evlist__set_leader(evlist);
144
145 if (evlist->cpus->map[0] < 0)
146 opts->no_inherit = true;
147
148 use_comm_exec = perf_can_comm_exec();
149
150 evlist__for_each(evlist, evsel) {
151 perf_evsel__config(evsel, opts);
152 if (evsel->tracking && use_comm_exec)
153 evsel->attr.comm_exec = 1;
154 }
155
156 if (opts->full_auxtrace) {
157 /*
158 * Need to be able to synthesize and parse selected events with
159 * arbitrary sample types, which requires always being able to
160 * match the id.
161 */
162 use_sample_identifier = perf_can_sample_identifier();
163 evlist__for_each(evlist, evsel)
164 perf_evsel__set_sample_id(evsel, use_sample_identifier);
165 } else if (evlist->nr_entries > 1) {
166 struct perf_evsel *first = perf_evlist__first(evlist);
167
168 evlist__for_each(evlist, evsel) {
169 if (evsel->attr.sample_type == first->attr.sample_type)
170 continue;
171 use_sample_identifier = perf_can_sample_identifier();
172 break;
173 }
174 evlist__for_each(evlist, evsel)
175 perf_evsel__set_sample_id(evsel, use_sample_identifier);
176 }
177
178 perf_evlist__set_id_pos(evlist);
179}
180
181static int get_max_rate(unsigned int *rate)
182{
183 return sysctl__read_int("kernel/perf_event_max_sample_rate", (int *)rate);
184}
185
186static int record_opts__config_freq(struct record_opts *opts)
187{
188 bool user_freq = opts->user_freq != UINT_MAX;
189 unsigned int max_rate;
190
191 if (opts->user_interval != ULLONG_MAX)
192 opts->default_interval = opts->user_interval;
193 if (user_freq)
194 opts->freq = opts->user_freq;
195
196 /*
197 * User specified count overrides default frequency.
198 */
199 if (opts->default_interval)
200 opts->freq = 0;
201 else if (opts->freq) {
202 opts->default_interval = opts->freq;
203 } else {
204 pr_err("frequency and count are zero, aborting\n");
205 return -1;
206 }
207
208 if (get_max_rate(&max_rate))
209 return 0;
210
211 /*
212 * User specified frequency is over current maximum.
213 */
214 if (user_freq && (max_rate < opts->freq)) {
215 pr_err("Maximum frequency rate (%u) reached.\n"
216 "Please use -F freq option with lower value or consider\n"
217 "tweaking /proc/sys/kernel/perf_event_max_sample_rate.\n",
218 max_rate);
219 return -1;
220 }
221
222 /*
223 * Default frequency is over current maximum.
224 */
225 if (max_rate < opts->freq) {
226 pr_warning("Lowering default frequency rate to %u.\n"
227 "Please consider tweaking "
228 "/proc/sys/kernel/perf_event_max_sample_rate.\n",
229 max_rate);
230 opts->freq = max_rate;
231 }
232
233 return 0;
234}
235
236int record_opts__config(struct record_opts *opts)
237{
238 return record_opts__config_freq(opts);
239}
240
241bool perf_evlist__can_select_event(struct perf_evlist *evlist, const char *str)
242{
243 struct perf_evlist *temp_evlist;
244 struct perf_evsel *evsel;
245 int err, fd, cpu;
246 bool ret = false;
247 pid_t pid = -1;
248
249 temp_evlist = perf_evlist__new();
250 if (!temp_evlist)
251 return false;
252
253 err = parse_events(temp_evlist, str, NULL);
254 if (err)
255 goto out_delete;
256
257 evsel = perf_evlist__last(temp_evlist);
258
259 if (!evlist || cpu_map__empty(evlist->cpus)) {
260 struct cpu_map *cpus = cpu_map__new(NULL);
261
262 cpu = cpus ? cpus->map[0] : 0;
263 cpu_map__put(cpus);
264 } else {
265 cpu = evlist->cpus->map[0];
266 }
267
268 while (1) {
269 fd = sys_perf_event_open(&evsel->attr, pid, cpu, -1,
270 perf_event_open_cloexec_flag());
271 if (fd < 0) {
272 if (pid == -1 && errno == EACCES) {
273 pid = 0;
274 continue;
275 }
276 goto out_delete;
277 }
278 break;
279 }
280 close(fd);
281 ret = true;
282
283out_delete:
284 perf_evlist__delete(temp_evlist);
285 return ret;
286}
1#include "evlist.h"
2#include "evsel.h"
3#include "cpumap.h"
4#include "parse-events.h"
5#include <api/fs/fs.h>
6#include "util.h"
7
8typedef void (*setup_probe_fn_t)(struct perf_evsel *evsel);
9
10static int perf_do_probe_api(setup_probe_fn_t fn, int cpu, const char *str)
11{
12 struct perf_evlist *evlist;
13 struct perf_evsel *evsel;
14 int err = -EAGAIN, fd;
15
16 evlist = perf_evlist__new();
17 if (!evlist)
18 return -ENOMEM;
19
20 if (parse_events(evlist, str))
21 goto out_delete;
22
23 evsel = perf_evlist__first(evlist);
24
25 fd = sys_perf_event_open(&evsel->attr, -1, cpu, -1, 0);
26 if (fd < 0)
27 goto out_delete;
28 close(fd);
29
30 fn(evsel);
31
32 fd = sys_perf_event_open(&evsel->attr, -1, cpu, -1, 0);
33 if (fd < 0) {
34 if (errno == EINVAL)
35 err = -EINVAL;
36 goto out_delete;
37 }
38 close(fd);
39 err = 0;
40
41out_delete:
42 perf_evlist__delete(evlist);
43 return err;
44}
45
46static bool perf_probe_api(setup_probe_fn_t fn)
47{
48 const char *try[] = {"cycles:u", "instructions:u", "cpu-clock", NULL};
49 struct cpu_map *cpus;
50 int cpu, ret, i = 0;
51
52 cpus = cpu_map__new(NULL);
53 if (!cpus)
54 return false;
55 cpu = cpus->map[0];
56 cpu_map__delete(cpus);
57
58 do {
59 ret = perf_do_probe_api(fn, cpu, try[i++]);
60 if (!ret)
61 return true;
62 } while (ret == -EAGAIN && try[i]);
63
64 return false;
65}
66
67static void perf_probe_sample_identifier(struct perf_evsel *evsel)
68{
69 evsel->attr.sample_type |= PERF_SAMPLE_IDENTIFIER;
70}
71
72bool perf_can_sample_identifier(void)
73{
74 return perf_probe_api(perf_probe_sample_identifier);
75}
76
77void perf_evlist__config(struct perf_evlist *evlist, struct record_opts *opts)
78{
79 struct perf_evsel *evsel;
80 bool use_sample_identifier = false;
81
82 /*
83 * Set the evsel leader links before we configure attributes,
84 * since some might depend on this info.
85 */
86 if (opts->group)
87 perf_evlist__set_leader(evlist);
88
89 if (evlist->cpus->map[0] < 0)
90 opts->no_inherit = true;
91
92 evlist__for_each(evlist, evsel)
93 perf_evsel__config(evsel, opts);
94
95 if (evlist->nr_entries > 1) {
96 struct perf_evsel *first = perf_evlist__first(evlist);
97
98 evlist__for_each(evlist, evsel) {
99 if (evsel->attr.sample_type == first->attr.sample_type)
100 continue;
101 use_sample_identifier = perf_can_sample_identifier();
102 break;
103 }
104 evlist__for_each(evlist, evsel)
105 perf_evsel__set_sample_id(evsel, use_sample_identifier);
106 }
107
108 perf_evlist__set_id_pos(evlist);
109}
110
111static int get_max_rate(unsigned int *rate)
112{
113 char path[PATH_MAX];
114 const char *procfs = procfs__mountpoint();
115
116 if (!procfs)
117 return -1;
118
119 snprintf(path, PATH_MAX,
120 "%s/sys/kernel/perf_event_max_sample_rate", procfs);
121
122 return filename__read_int(path, (int *) rate);
123}
124
125static int record_opts__config_freq(struct record_opts *opts)
126{
127 bool user_freq = opts->user_freq != UINT_MAX;
128 unsigned int max_rate;
129
130 if (opts->user_interval != ULLONG_MAX)
131 opts->default_interval = opts->user_interval;
132 if (user_freq)
133 opts->freq = opts->user_freq;
134
135 /*
136 * User specified count overrides default frequency.
137 */
138 if (opts->default_interval)
139 opts->freq = 0;
140 else if (opts->freq) {
141 opts->default_interval = opts->freq;
142 } else {
143 pr_err("frequency and count are zero, aborting\n");
144 return -1;
145 }
146
147 if (get_max_rate(&max_rate))
148 return 0;
149
150 /*
151 * User specified frequency is over current maximum.
152 */
153 if (user_freq && (max_rate < opts->freq)) {
154 pr_err("Maximum frequency rate (%u) reached.\n"
155 "Please use -F freq option with lower value or consider\n"
156 "tweaking /proc/sys/kernel/perf_event_max_sample_rate.\n",
157 max_rate);
158 return -1;
159 }
160
161 /*
162 * Default frequency is over current maximum.
163 */
164 if (max_rate < opts->freq) {
165 pr_warning("Lowering default frequency rate to %u.\n"
166 "Please consider tweaking "
167 "/proc/sys/kernel/perf_event_max_sample_rate.\n",
168 max_rate);
169 opts->freq = max_rate;
170 }
171
172 return 0;
173}
174
175int record_opts__config(struct record_opts *opts)
176{
177 return record_opts__config_freq(opts);
178}
179
180bool perf_evlist__can_select_event(struct perf_evlist *evlist, const char *str)
181{
182 struct perf_evlist *temp_evlist;
183 struct perf_evsel *evsel;
184 int err, fd, cpu;
185 bool ret = false;
186
187 temp_evlist = perf_evlist__new();
188 if (!temp_evlist)
189 return false;
190
191 err = parse_events(temp_evlist, str);
192 if (err)
193 goto out_delete;
194
195 evsel = perf_evlist__last(temp_evlist);
196
197 if (!evlist || cpu_map__empty(evlist->cpus)) {
198 struct cpu_map *cpus = cpu_map__new(NULL);
199
200 cpu = cpus ? cpus->map[0] : 0;
201 cpu_map__delete(cpus);
202 } else {
203 cpu = evlist->cpus->map[0];
204 }
205
206 fd = sys_perf_event_open(&evsel->attr, -1, cpu, -1, 0);
207 if (fd >= 0) {
208 close(fd);
209 ret = true;
210 }
211
212out_delete:
213 perf_evlist__delete(temp_evlist);
214 return ret;
215}