xref: /openbmc/linux/tools/lib/perf/evsel.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <errno.h>
3 #include <unistd.h>
4 #include <sys/syscall.h>
5 #include <perf/evsel.h>
6 #include <perf/cpumap.h>
7 #include <perf/threadmap.h>
8 #include <linux/list.h>
9 #include <internal/evsel.h>
10 #include <linux/zalloc.h>
11 #include <stdlib.h>
12 #include <internal/xyarray.h>
13 #include <internal/cpumap.h>
14 #include <internal/threadmap.h>
15 #include <internal/lib.h>
16 #include <linux/string.h>
17 #include <sys/ioctl.h>
18 
19 void perf_evsel__init(struct perf_evsel *evsel, struct perf_event_attr *attr)
20 {
21 	INIT_LIST_HEAD(&evsel->node);
22 	evsel->attr = *attr;
23 }
24 
25 struct perf_evsel *perf_evsel__new(struct perf_event_attr *attr)
26 {
27 	struct perf_evsel *evsel = zalloc(sizeof(*evsel));
28 
29 	if (evsel != NULL)
30 		perf_evsel__init(evsel, attr);
31 
32 	return evsel;
33 }
34 
35 void perf_evsel__delete(struct perf_evsel *evsel)
36 {
37 	free(evsel);
38 }
39 
40 #define FD(e, x, y) (*(int *) xyarray__entry(e->fd, x, y))
41 
42 int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
43 {
44 	evsel->fd = xyarray__new(ncpus, nthreads, sizeof(int));
45 
46 	if (evsel->fd) {
47 		int cpu, thread;
48 		for (cpu = 0; cpu < ncpus; cpu++) {
49 			for (thread = 0; thread < nthreads; thread++) {
50 				FD(evsel, cpu, thread) = -1;
51 			}
52 		}
53 	}
54 
55 	return evsel->fd != NULL ? 0 : -ENOMEM;
56 }
57 
58 static int
59 sys_perf_event_open(struct perf_event_attr *attr,
60 		    pid_t pid, int cpu, int group_fd,
61 		    unsigned long flags)
62 {
63 	return syscall(__NR_perf_event_open, attr, pid, cpu, group_fd, flags);
64 }
65 
66 int perf_evsel__open(struct perf_evsel *evsel, struct perf_cpu_map *cpus,
67 		     struct perf_thread_map *threads)
68 {
69 	int cpu, thread, err = 0;
70 
71 	if (cpus == NULL) {
72 		static struct perf_cpu_map *empty_cpu_map;
73 
74 		if (empty_cpu_map == NULL) {
75 			empty_cpu_map = perf_cpu_map__dummy_new();
76 			if (empty_cpu_map == NULL)
77 				return -ENOMEM;
78 		}
79 
80 		cpus = empty_cpu_map;
81 	}
82 
83 	if (threads == NULL) {
84 		static struct perf_thread_map *empty_thread_map;
85 
86 		if (empty_thread_map == NULL) {
87 			empty_thread_map = perf_thread_map__new_dummy();
88 			if (empty_thread_map == NULL)
89 				return -ENOMEM;
90 		}
91 
92 		threads = empty_thread_map;
93 	}
94 
95 	if (evsel->fd == NULL &&
96 	    perf_evsel__alloc_fd(evsel, cpus->nr, threads->nr) < 0)
97 		return -ENOMEM;
98 
99 	for (cpu = 0; cpu < cpus->nr; cpu++) {
100 		for (thread = 0; thread < threads->nr; thread++) {
101 			int fd;
102 
103 			fd = sys_perf_event_open(&evsel->attr,
104 						 threads->map[thread].pid,
105 						 cpus->map[cpu], -1, 0);
106 
107 			if (fd < 0)
108 				return -errno;
109 
110 			FD(evsel, cpu, thread) = fd;
111 		}
112 	}
113 
114 	return err;
115 }
116 
117 static void perf_evsel__close_fd_cpu(struct perf_evsel *evsel, int cpu)
118 {
119 	int thread;
120 
121 	for (thread = 0; thread < xyarray__max_y(evsel->fd); ++thread) {
122 		if (FD(evsel, cpu, thread) >= 0)
123 			close(FD(evsel, cpu, thread));
124 		FD(evsel, cpu, thread) = -1;
125 	}
126 }
127 
128 void perf_evsel__close_fd(struct perf_evsel *evsel)
129 {
130 	int cpu;
131 
132 	for (cpu = 0; cpu < xyarray__max_x(evsel->fd); cpu++)
133 		perf_evsel__close_fd_cpu(evsel, cpu);
134 }
135 
136 void perf_evsel__free_fd(struct perf_evsel *evsel)
137 {
138 	xyarray__delete(evsel->fd);
139 	evsel->fd = NULL;
140 }
141 
142 void perf_evsel__close(struct perf_evsel *evsel)
143 {
144 	if (evsel->fd == NULL)
145 		return;
146 
147 	perf_evsel__close_fd(evsel);
148 	perf_evsel__free_fd(evsel);
149 }
150 
151 void perf_evsel__close_cpu(struct perf_evsel *evsel, int cpu)
152 {
153 	if (evsel->fd == NULL)
154 		return;
155 
156 	perf_evsel__close_fd_cpu(evsel, cpu);
157 }
158 
159 int perf_evsel__read_size(struct perf_evsel *evsel)
160 {
161 	u64 read_format = evsel->attr.read_format;
162 	int entry = sizeof(u64); /* value */
163 	int size = 0;
164 	int nr = 1;
165 
166 	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
167 		size += sizeof(u64);
168 
169 	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
170 		size += sizeof(u64);
171 
172 	if (read_format & PERF_FORMAT_ID)
173 		entry += sizeof(u64);
174 
175 	if (read_format & PERF_FORMAT_GROUP) {
176 		nr = evsel->nr_members;
177 		size += sizeof(u64);
178 	}
179 
180 	size += entry * nr;
181 	return size;
182 }
183 
184 int perf_evsel__read(struct perf_evsel *evsel, int cpu, int thread,
185 		     struct perf_counts_values *count)
186 {
187 	size_t size = perf_evsel__read_size(evsel);
188 
189 	memset(count, 0, sizeof(*count));
190 
191 	if (FD(evsel, cpu, thread) < 0)
192 		return -EINVAL;
193 
194 	if (readn(FD(evsel, cpu, thread), count->values, size) <= 0)
195 		return -errno;
196 
197 	return 0;
198 }
199 
200 static int perf_evsel__run_ioctl(struct perf_evsel *evsel,
201 				 int ioc,  void *arg,
202 				 int cpu)
203 {
204 	int thread;
205 
206 	for (thread = 0; thread < xyarray__max_y(evsel->fd); thread++) {
207 		int fd = FD(evsel, cpu, thread),
208 		    err = ioctl(fd, ioc, arg);
209 
210 		if (err)
211 			return err;
212 	}
213 
214 	return 0;
215 }
216 
217 int perf_evsel__enable_cpu(struct perf_evsel *evsel, int cpu)
218 {
219 	return perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_ENABLE, NULL, cpu);
220 }
221 
222 int perf_evsel__enable(struct perf_evsel *evsel)
223 {
224 	int i;
225 	int err = 0;
226 
227 	for (i = 0; i < xyarray__max_x(evsel->fd) && !err; i++)
228 		err = perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_ENABLE, NULL, i);
229 	return err;
230 }
231 
232 int perf_evsel__disable_cpu(struct perf_evsel *evsel, int cpu)
233 {
234 	return perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_DISABLE, NULL, cpu);
235 }
236 
237 int perf_evsel__disable(struct perf_evsel *evsel)
238 {
239 	int i;
240 	int err = 0;
241 
242 	for (i = 0; i < xyarray__max_x(evsel->fd) && !err; i++)
243 		err = perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_DISABLE, NULL, i);
244 	return err;
245 }
246 
247 int perf_evsel__apply_filter(struct perf_evsel *evsel, const char *filter)
248 {
249 	int err = 0, i;
250 
251 	for (i = 0; i < evsel->cpus->nr && !err; i++)
252 		err = perf_evsel__run_ioctl(evsel,
253 				     PERF_EVENT_IOC_SET_FILTER,
254 				     (void *)filter, i);
255 	return err;
256 }
257 
258 struct perf_cpu_map *perf_evsel__cpus(struct perf_evsel *evsel)
259 {
260 	return evsel->cpus;
261 }
262 
263 struct perf_thread_map *perf_evsel__threads(struct perf_evsel *evsel)
264 {
265 	return evsel->threads;
266 }
267 
268 struct perf_event_attr *perf_evsel__attr(struct perf_evsel *evsel)
269 {
270 	return &evsel->attr;
271 }
272 
273 int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
274 {
275 	if (ncpus == 0 || nthreads == 0)
276 		return 0;
277 
278 	if (evsel->system_wide)
279 		nthreads = 1;
280 
281 	evsel->sample_id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
282 	if (evsel->sample_id == NULL)
283 		return -ENOMEM;
284 
285 	evsel->id = zalloc(ncpus * nthreads * sizeof(u64));
286 	if (evsel->id == NULL) {
287 		xyarray__delete(evsel->sample_id);
288 		evsel->sample_id = NULL;
289 		return -ENOMEM;
290 	}
291 
292 	return 0;
293 }
294 
295 void perf_evsel__free_id(struct perf_evsel *evsel)
296 {
297 	xyarray__delete(evsel->sample_id);
298 	evsel->sample_id = NULL;
299 	zfree(&evsel->id);
300 	evsel->ids = 0;
301 }
302