xref: /linux/tools/perf/util/pfm.c (revision f4f346c3465949ebba80c6cc52cd8d2eeaa545fd)
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 <string.h>
19 #include <linux/kernel.h>
20 #include <perfmon/pfmlib_perf_event.h>
21 
libpfm_initialize(void)22 static void libpfm_initialize(void)
23 {
24 	int ret;
25 
26 	ret = pfm_initialize();
27 	if (ret != PFM_SUCCESS) {
28 		ui__warning("libpfm failed to initialize: %s\n",
29 			pfm_strerror(ret));
30 	}
31 }
32 
parse_libpfm_events_option(const struct option * opt,const char * str,int unset __maybe_unused)33 int parse_libpfm_events_option(const struct option *opt, const char *str,
34 			int unset __maybe_unused)
35 {
36 	struct evlist *evlist = *(struct evlist **)opt->value;
37 	struct perf_event_attr attr;
38 	struct perf_pmu *pmu;
39 	struct evsel *evsel, *grp_leader = NULL;
40 	char *p, *q, *p_orig;
41 	const char *sep;
42 	int grp_evt = -1;
43 	int ret;
44 
45 	libpfm_initialize();
46 
47 	p_orig = p = strdup(str);
48 	if (!p)
49 		return -1;
50 
51 	for (q = p; strsep(&p, ",{}"); q = p) {
52 		sep = p ? str + (p - p_orig - 1) : "";
53 		if (*sep == '{') {
54 			if (grp_evt > -1) {
55 				ui__error(
56 					"nested event groups not supported\n");
57 				goto error;
58 			}
59 			grp_evt++;
60 		}
61 
62 		/* no event */
63 		if (*q == '\0') {
64 			if (*sep == '}') {
65 				if (grp_evt < 0) {
66 					ui__error("cannot close a non-existing event group\n");
67 					goto error;
68 				}
69 				grp_evt--;
70 			}
71 			continue;
72 		}
73 
74 		memset(&attr, 0, sizeof(attr));
75 		event_attr_init(&attr);
76 
77 		ret = pfm_get_perf_event_encoding(q, PFM_PLM0|PFM_PLM3,
78 						&attr, NULL, NULL);
79 
80 		if (ret != PFM_SUCCESS) {
81 			ui__error("failed to parse event %s : %s\n", str,
82 				  pfm_strerror(ret));
83 			goto error;
84 		}
85 
86 		pmu = perf_pmus__find_by_type((unsigned int)attr.type);
87 		evsel = parse_events__add_event(evlist->core.nr_entries,
88 						&attr, q, /*metric_id=*/NULL,
89 						pmu);
90 		if (evsel == NULL)
91 			goto error;
92 
93 		evsel->is_libpfm_event = true;
94 
95 		evlist__add(evlist, evsel);
96 
97 		if (grp_evt == 0)
98 			grp_leader = evsel;
99 
100 		if (grp_evt > -1) {
101 			evsel__set_leader(evsel, grp_leader);
102 			grp_leader->core.nr_members++;
103 			grp_evt++;
104 		}
105 
106 		if (*sep == '}') {
107 			if (grp_evt < 0) {
108 				ui__error(
109 				   "cannot close a non-existing event group\n");
110 				goto error;
111 			}
112 			grp_leader = NULL;
113 			grp_evt = -1;
114 		}
115 	}
116 	free(p_orig);
117 	return 0;
118 error:
119 	free(p_orig);
120 	return -1;
121 }
122 
is_libpfm_event_supported(const char * name,struct perf_cpu_map * cpus,struct perf_thread_map * threads)123 static bool is_libpfm_event_supported(const char *name, struct perf_cpu_map *cpus,
124 				      struct perf_thread_map *threads)
125 {
126 	struct perf_pmu *pmu;
127 	struct evsel *evsel;
128 	struct perf_event_attr attr = {};
129 	bool result = true;
130 	int ret;
131 
132 	ret = pfm_get_perf_event_encoding(name, PFM_PLM0|PFM_PLM3,
133 					  &attr, NULL, NULL);
134 	if (ret != PFM_SUCCESS)
135 		return false;
136 
137 	pmu = perf_pmus__find_by_type((unsigned int)attr.type);
138 	evsel = parse_events__add_event(0, &attr, name, /*metric_id=*/NULL, pmu);
139 	if (evsel == NULL)
140 		return false;
141 
142 	evsel->is_libpfm_event = true;
143 
144 	ret = evsel__open(evsel, cpus, threads);
145 	if (ret == -EACCES) {
146 		/*
147 		 * This happens if the paranoid value
148 		 * /proc/sys/kernel/perf_event_paranoid is set to 2
149 		 * Re-run with exclude_kernel set; we don't do that
150 		 * by default as some ARM machines do not support it.
151 		 *
152 		 */
153 		evsel->core.attr.exclude_kernel = 1;
154 		ret = evsel__open(evsel, cpus, threads);
155 
156 	}
157 	if (ret < 0)
158 		result = false;
159 
160 	evsel__close(evsel);
161 	evsel__delete(evsel);
162 
163 	return result;
164 }
165 
166 static const char *srcs[PFM_ATTR_CTRL_MAX] = {
167 	[PFM_ATTR_CTRL_UNKNOWN] = "???",
168 	[PFM_ATTR_CTRL_PMU] = "PMU",
169 	[PFM_ATTR_CTRL_PERF_EVENT] = "perf_event",
170 };
171 
172 static void
print_attr_flags(struct strbuf * buf,const pfm_event_attr_info_t * info)173 print_attr_flags(struct strbuf *buf, const pfm_event_attr_info_t *info)
174 {
175 	if (info->is_dfl)
176 		strbuf_addf(buf, "[default] ");
177 
178 	if (info->is_precise)
179 		strbuf_addf(buf, "[precise] ");
180 }
181 
182 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)183 print_libpfm_event(const struct print_callbacks *print_cb, void *print_state,
184 		const pfm_pmu_info_t *pinfo, const pfm_event_info_t *info,
185 		struct strbuf *buf)
186 {
187 	int j, ret;
188 	char topic[80], name[80];
189 	struct perf_cpu_map *cpus = perf_cpu_map__empty_new(1);
190 	struct perf_thread_map *threads = thread_map__new_by_tid(0);
191 
192 	strbuf_setlen(buf, 0);
193 	snprintf(topic, sizeof(topic), "pfm %s", pinfo->name);
194 
195 	snprintf(name, sizeof(name), "%s::%s", pinfo->name, info->name);
196 	strbuf_addf(buf, "Code: 0x%"PRIx64"\n", info->code);
197 
198 	pfm_for_each_event_attr(j, info) {
199 		pfm_event_attr_info_t ainfo;
200 		const char *src;
201 
202 		ainfo.size = sizeof(ainfo);
203 		ret = pfm_get_event_attr_info(info->idx, j, PFM_OS_PERF_EVENT_EXT, &ainfo);
204 		if (ret != PFM_SUCCESS)
205 			continue;
206 
207 		if (ainfo.ctrl >= PFM_ATTR_CTRL_MAX)
208 			ainfo.ctrl = PFM_ATTR_CTRL_UNKNOWN;
209 
210 		src = srcs[ainfo.ctrl];
211 		switch (ainfo.type) {
212 		case PFM_ATTR_UMASK: /* Ignore for now */
213 			break;
214 		case PFM_ATTR_MOD_BOOL:
215 			strbuf_addf(buf, " Modif: %s: [%s] : %s (boolean)\n", src,
216 				    ainfo.name, ainfo.desc);
217 			break;
218 		case PFM_ATTR_MOD_INTEGER:
219 			strbuf_addf(buf, " Modif: %s: [%s] : %s (integer)\n", src,
220 				    ainfo.name, ainfo.desc);
221 			break;
222 		case PFM_ATTR_NONE:
223 		case PFM_ATTR_RAW_UMASK:
224 		case PFM_ATTR_MAX:
225 		default:
226 			strbuf_addf(buf, " Attr: %s: [%s] : %s\n", src,
227 				    ainfo.name, ainfo.desc);
228 		}
229 	}
230 
231 	if (is_libpfm_event_supported(name, cpus, threads)) {
232 		print_cb->print_event(print_state, topic, pinfo->name,
233 				      /*pmu_type=*/PERF_TYPE_RAW,
234 				      name, info->equiv,
235 				      /*scale_unit=*/NULL,
236 				      /*deprecated=*/NULL, "PFM event",
237 				      info->desc, /*long_desc=*/NULL,
238 				      /*encoding_desc=*/buf->buf);
239 	}
240 
241 	pfm_for_each_event_attr(j, info) {
242 		pfm_event_attr_info_t ainfo;
243 		const char *src;
244 
245 		strbuf_setlen(buf, 0);
246 
247 		ainfo.size = sizeof(ainfo);
248 		ret = pfm_get_event_attr_info(info->idx, j, PFM_OS_PERF_EVENT_EXT, &ainfo);
249 		if (ret != PFM_SUCCESS)
250 			continue;
251 
252 		if (ainfo.ctrl >= PFM_ATTR_CTRL_MAX)
253 			ainfo.ctrl = PFM_ATTR_CTRL_UNKNOWN;
254 
255 		src = srcs[ainfo.ctrl];
256 		if (ainfo.type == PFM_ATTR_UMASK) {
257 			strbuf_addf(buf, "Umask: 0x%02"PRIx64" : %s: ",
258 				ainfo.code, src);
259 			print_attr_flags(buf, &ainfo);
260 			snprintf(name, sizeof(name), "%s::%s:%s",
261 				 pinfo->name, info->name, ainfo.name);
262 
263 			if (!is_libpfm_event_supported(name, cpus, threads))
264 				continue;
265 
266 			print_cb->print_event(print_state,
267 					topic,
268 					pinfo->name,
269 					/*pmu_type=*/PERF_TYPE_RAW,
270 					name, /*alias=*/NULL,
271 					/*scale_unit=*/NULL,
272 					/*deprecated=*/NULL, "PFM event",
273 					ainfo.desc, /*long_desc=*/NULL,
274 					/*encoding_desc=*/buf->buf);
275 		}
276 	}
277 
278 	perf_cpu_map__put(cpus);
279 	perf_thread_map__put(threads);
280 }
281 
print_libpfm_events(const struct print_callbacks * print_cb,void * print_state)282 void print_libpfm_events(const struct print_callbacks *print_cb, void *print_state)
283 {
284 	pfm_event_info_t info;
285 	pfm_pmu_info_t pinfo;
286 	int p, ret;
287 	struct strbuf storage;
288 
289 	libpfm_initialize();
290 
291 	/* initialize to zero to indicate ABI version */
292 	info.size  = sizeof(info);
293 	pinfo.size = sizeof(pinfo);
294 
295 	strbuf_init(&storage, 2048);
296 
297 	pfm_for_all_pmus(p) {
298 		ret = pfm_get_pmu_info(p, &pinfo);
299 		if (ret != PFM_SUCCESS)
300 			continue;
301 
302 		/* only print events that are supported by host HW */
303 		if (!pinfo.is_present)
304 			continue;
305 
306 		/* handled by perf directly */
307 		if (pinfo.pmu == PFM_PMU_PERF_EVENT)
308 			continue;
309 
310 		for (int i = pinfo.first_event; i != -1; i = pfm_get_event_next(i)) {
311 			ret = pfm_get_event_info(i, PFM_OS_PERF_EVENT_EXT,
312 						&info);
313 			if (ret != PFM_SUCCESS)
314 				continue;
315 
316 			print_libpfm_event(print_cb, print_state, &pinfo, &info, &storage);
317 		}
318 	}
319 	strbuf_release(&storage);
320 }
321