xref: /linux/tools/perf/util/pfm.c (revision 9e906a9dead17d81d6c2687f65e159231d0e3286)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Support for libpfm4 event encoding.
4  *
5  * Copyright 2020 Google LLC.
6  */
7 #include "util/cpumap.h"
8 #include "util/debug.h"
9 #include "util/event.h"
10 #include "util/evlist.h"
11 #include "util/evsel.h"
12 #include "util/parse-events.h"
13 #include "util/pmus.h"
14 #include "util/pfm.h"
15 #include "util/strbuf.h"
16 #include "util/thread_map.h"
17 
18 #include <errno.h>
19 #include <string.h>
20 #include <linux/kernel.h>
21 #include <perfmon/pfmlib_perf_event.h>
22 
libpfm_initialize(void)23 static void libpfm_initialize(void)
24 {
25 	int ret;
26 
27 	ret = pfm_initialize();
28 	if (ret != PFM_SUCCESS) {
29 		ui__warning("libpfm failed to initialize: %s\n",
30 			pfm_strerror(ret));
31 	}
32 }
33 
parse_libpfm_events_option(const struct option * opt,const char * str,int unset __maybe_unused)34 int parse_libpfm_events_option(const struct option *opt, const char *str,
35 			int unset __maybe_unused)
36 {
37 	struct evlist *evlist = *(struct evlist **)opt->value;
38 	struct perf_event_attr attr;
39 	struct perf_pmu *pmu;
40 	struct evsel *evsel, *grp_leader = NULL;
41 	char *p, *q, *p_orig;
42 	const char *sep;
43 	int grp_evt = -1;
44 	int ret;
45 
46 	libpfm_initialize();
47 
48 	p_orig = p = strdup(str);
49 	if (!p)
50 		return -1;
51 
52 	for (q = p; strsep(&p, ",{}"); q = p) {
53 		sep = p ? str + (p - p_orig - 1) : "";
54 		if (*sep == '{') {
55 			if (grp_evt > -1) {
56 				ui__error(
57 					"nested event groups not supported\n");
58 				goto error;
59 			}
60 			grp_evt++;
61 		}
62 
63 		/* no event */
64 		if (*q == '\0') {
65 			if (*sep == '}') {
66 				if (grp_evt < 0) {
67 					ui__error("cannot close a non-existing event group\n");
68 					goto error;
69 				}
70 				grp_evt--;
71 			}
72 			continue;
73 		}
74 
75 		memset(&attr, 0, sizeof(attr));
76 		event_attr_init(&attr);
77 
78 		ret = pfm_get_perf_event_encoding(q, PFM_PLM0|PFM_PLM3,
79 						&attr, NULL, NULL);
80 
81 		if (ret != PFM_SUCCESS) {
82 			ui__error("failed to parse event %s : %s\n", str,
83 				  pfm_strerror(ret));
84 			goto error;
85 		}
86 
87 		pmu = perf_pmus__find_by_type((unsigned int)attr.type);
88 		evsel = parse_events__add_event(evlist->core.nr_entries,
89 						&attr, q, /*metric_id=*/NULL,
90 						pmu);
91 		if (evsel == NULL)
92 			goto error;
93 
94 		evsel->is_libpfm_event = true;
95 
96 		evlist__add(evlist, evsel);
97 
98 		if (grp_evt == 0)
99 			grp_leader = evsel;
100 
101 		if (grp_evt > -1) {
102 			evsel__set_leader(evsel, grp_leader);
103 			grp_leader->core.nr_members++;
104 			grp_evt++;
105 		}
106 
107 		if (*sep == '}') {
108 			if (grp_evt < 0) {
109 				ui__error(
110 				   "cannot close a non-existing event group\n");
111 				goto error;
112 			}
113 			grp_leader = NULL;
114 			grp_evt = -1;
115 		}
116 	}
117 	free(p_orig);
118 	return 0;
119 error:
120 	free(p_orig);
121 	return -1;
122 }
123 
is_libpfm_event_supported(const char * name,struct perf_cpu_map * cpus,struct perf_thread_map * threads)124 static bool is_libpfm_event_supported(const char *name, struct perf_cpu_map *cpus,
125 				      struct perf_thread_map *threads)
126 {
127 	struct perf_pmu *pmu;
128 	struct evsel *evsel;
129 	struct perf_event_attr attr = {};
130 	bool result = true;
131 	int ret;
132 
133 	ret = pfm_get_perf_event_encoding(name, PFM_PLM0|PFM_PLM3,
134 					  &attr, NULL, NULL);
135 	if (ret != PFM_SUCCESS)
136 		return false;
137 
138 	pmu = perf_pmus__find_by_type((unsigned int)attr.type);
139 	evsel = parse_events__add_event(0, &attr, name, /*metric_id=*/NULL, pmu);
140 	if (evsel == NULL)
141 		return false;
142 
143 	evsel->is_libpfm_event = true;
144 
145 	ret = evsel__open(evsel, cpus, threads);
146 	if (ret == -EACCES) {
147 		/*
148 		 * This happens if the paranoid value
149 		 * /proc/sys/kernel/perf_event_paranoid is set to 2
150 		 * Re-run with exclude_kernel set; we don't do that
151 		 * by default as some ARM machines do not support it.
152 		 *
153 		 */
154 		evsel->core.attr.exclude_kernel = 1;
155 		ret = evsel__open(evsel, cpus, threads);
156 
157 	}
158 	if (ret < 0)
159 		result = false;
160 
161 	evsel__close(evsel);
162 	evsel__delete(evsel);
163 
164 	return result;
165 }
166 
167 static const char *srcs[PFM_ATTR_CTRL_MAX] = {
168 	[PFM_ATTR_CTRL_UNKNOWN] = "???",
169 	[PFM_ATTR_CTRL_PMU] = "PMU",
170 	[PFM_ATTR_CTRL_PERF_EVENT] = "perf_event",
171 };
172 
173 static void
print_attr_flags(struct strbuf * buf,const pfm_event_attr_info_t * info)174 print_attr_flags(struct strbuf *buf, const pfm_event_attr_info_t *info)
175 {
176 	if (info->is_dfl)
177 		strbuf_addf(buf, "[default] ");
178 
179 	if (info->is_precise)
180 		strbuf_addf(buf, "[precise] ");
181 }
182 
183 static void
print_libpfm_event(const struct print_callbacks * print_cb,void * print_state,const pfm_pmu_info_t * pinfo,const pfm_event_info_t * info,struct strbuf * buf)184 print_libpfm_event(const struct print_callbacks *print_cb, void *print_state,
185 		const pfm_pmu_info_t *pinfo, const pfm_event_info_t *info,
186 		struct strbuf *buf)
187 {
188 	int j, ret;
189 	char topic[80], name[80];
190 	struct perf_cpu_map *cpus = perf_cpu_map__empty_new(1);
191 	struct perf_thread_map *threads = thread_map__new_by_tid(0);
192 
193 	strbuf_setlen(buf, 0);
194 	snprintf(topic, sizeof(topic), "pfm %s", pinfo->name);
195 
196 	snprintf(name, sizeof(name), "%s::%s", pinfo->name, info->name);
197 	strbuf_addf(buf, "Code: 0x%"PRIx64"\n", info->code);
198 
199 	pfm_for_each_event_attr(j, info) {
200 		pfm_event_attr_info_t ainfo;
201 		const char *src;
202 
203 		ainfo.size = sizeof(ainfo);
204 		ret = pfm_get_event_attr_info(info->idx, j, PFM_OS_PERF_EVENT_EXT, &ainfo);
205 		if (ret != PFM_SUCCESS)
206 			continue;
207 
208 		if (ainfo.ctrl >= PFM_ATTR_CTRL_MAX)
209 			ainfo.ctrl = PFM_ATTR_CTRL_UNKNOWN;
210 
211 		src = srcs[ainfo.ctrl];
212 		switch (ainfo.type) {
213 		case PFM_ATTR_UMASK: /* Ignore for now */
214 			break;
215 		case PFM_ATTR_MOD_BOOL:
216 			strbuf_addf(buf, " Modif: %s: [%s] : %s (boolean)\n", src,
217 				    ainfo.name, ainfo.desc);
218 			break;
219 		case PFM_ATTR_MOD_INTEGER:
220 			strbuf_addf(buf, " Modif: %s: [%s] : %s (integer)\n", src,
221 				    ainfo.name, ainfo.desc);
222 			break;
223 		case PFM_ATTR_NONE:
224 		case PFM_ATTR_RAW_UMASK:
225 		case PFM_ATTR_MAX:
226 		default:
227 			strbuf_addf(buf, " Attr: %s: [%s] : %s\n", src,
228 				    ainfo.name, ainfo.desc);
229 		}
230 	}
231 
232 	if (is_libpfm_event_supported(name, cpus, threads)) {
233 		print_cb->print_event(print_state, topic, pinfo->name,
234 				      /*pmu_type=*/PERF_TYPE_RAW,
235 				      name, info->equiv,
236 				      /*scale_unit=*/NULL,
237 				      /*deprecated=*/NULL, "PFM event",
238 				      info->desc, /*long_desc=*/NULL,
239 				      /*encoding_desc=*/buf->buf);
240 	}
241 
242 	pfm_for_each_event_attr(j, info) {
243 		pfm_event_attr_info_t ainfo;
244 		const char *src;
245 
246 		strbuf_setlen(buf, 0);
247 
248 		ainfo.size = sizeof(ainfo);
249 		ret = pfm_get_event_attr_info(info->idx, j, PFM_OS_PERF_EVENT_EXT, &ainfo);
250 		if (ret != PFM_SUCCESS)
251 			continue;
252 
253 		if (ainfo.ctrl >= PFM_ATTR_CTRL_MAX)
254 			ainfo.ctrl = PFM_ATTR_CTRL_UNKNOWN;
255 
256 		src = srcs[ainfo.ctrl];
257 		if (ainfo.type == PFM_ATTR_UMASK) {
258 			strbuf_addf(buf, "Umask: 0x%02"PRIx64" : %s: ",
259 				ainfo.code, src);
260 			print_attr_flags(buf, &ainfo);
261 			snprintf(name, sizeof(name), "%s::%s:%s",
262 				 pinfo->name, info->name, ainfo.name);
263 
264 			if (!is_libpfm_event_supported(name, cpus, threads))
265 				continue;
266 
267 			print_cb->print_event(print_state,
268 					topic,
269 					pinfo->name,
270 					/*pmu_type=*/PERF_TYPE_RAW,
271 					name, /*alias=*/NULL,
272 					/*scale_unit=*/NULL,
273 					/*deprecated=*/NULL, "PFM event",
274 					ainfo.desc, /*long_desc=*/NULL,
275 					/*encoding_desc=*/buf->buf);
276 		}
277 	}
278 
279 	perf_cpu_map__put(cpus);
280 	perf_thread_map__put(threads);
281 }
282 
print_libpfm_events(const struct print_callbacks * print_cb,void * print_state)283 void print_libpfm_events(const struct print_callbacks *print_cb, void *print_state)
284 {
285 	pfm_event_info_t info;
286 	pfm_pmu_info_t pinfo;
287 	int p, ret;
288 	struct strbuf storage;
289 
290 	libpfm_initialize();
291 
292 	/* initialize to zero to indicate ABI version */
293 	info.size  = sizeof(info);
294 	pinfo.size = sizeof(pinfo);
295 
296 	strbuf_init(&storage, 2048);
297 
298 	pfm_for_all_pmus(p) {
299 		ret = pfm_get_pmu_info(p, &pinfo);
300 		if (ret != PFM_SUCCESS)
301 			continue;
302 
303 		/* only print events that are supported by host HW */
304 		if (!pinfo.is_present)
305 			continue;
306 
307 		/* handled by perf directly */
308 		if (pinfo.pmu == PFM_PMU_PERF_EVENT)
309 			continue;
310 
311 		for (int i = pinfo.first_event; i != -1; i = pfm_get_event_next(i)) {
312 			ret = pfm_get_event_info(i, PFM_OS_PERF_EVENT_EXT,
313 						&info);
314 			if (ret != PFM_SUCCESS)
315 				continue;
316 
317 			print_libpfm_event(print_cb, print_state, &pinfo, &info, &storage);
318 		}
319 	}
320 	strbuf_release(&storage);
321 }
322