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
22static 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
33int 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 * force loading of the PMU list
52 */
53 perf_pmus__scan(NULL);
54
55 for (q = p; strsep(&p, ",{}"); q = p) {
56 sep = p ? str + (p - p_orig - 1) : "";
57 if (*sep == '{') {
58 if (grp_evt > -1) {
59 ui__error(
60 "nested event groups not supported\n");
61 goto error;
62 }
63 grp_evt++;
64 }
65
66 /* no event */
67 if (*q == '\0') {
68 if (*sep == '}') {
69 if (grp_evt < 0) {
70 ui__error("cannot close a non-existing event group\n");
71 goto error;
72 }
73 grp_evt--;
74 }
75 continue;
76 }
77
78 memset(&attr, 0, sizeof(attr));
79 event_attr_init(&attr);
80
81 ret = pfm_get_perf_event_encoding(q, PFM_PLM0|PFM_PLM3,
82 &attr, NULL, NULL);
83
84 if (ret != PFM_SUCCESS) {
85 ui__error("failed to parse event %s : %s\n", str,
86 pfm_strerror(ret));
87 goto error;
88 }
89
90 pmu = perf_pmus__find_by_type((unsigned int)attr.type);
91 evsel = parse_events__add_event(evlist->core.nr_entries,
92 &attr, q, /*metric_id=*/NULL,
93 pmu);
94 if (evsel == NULL)
95 goto error;
96
97 evsel->is_libpfm_event = true;
98
99 evlist__add(evlist, evsel);
100
101 if (grp_evt == 0)
102 grp_leader = evsel;
103
104 if (grp_evt > -1) {
105 evsel__set_leader(evsel, grp_leader);
106 grp_leader->core.nr_members++;
107 grp_evt++;
108 }
109
110 if (*sep == '}') {
111 if (grp_evt < 0) {
112 ui__error(
113 "cannot close a non-existing event group\n");
114 goto error;
115 }
116 grp_leader = NULL;
117 grp_evt = -1;
118 }
119 }
120 free(p_orig);
121 return 0;
122error:
123 free(p_orig);
124 return -1;
125}
126
127static bool is_libpfm_event_supported(const char *name, struct perf_cpu_map *cpus,
128 struct perf_thread_map *threads)
129{
130 struct perf_pmu *pmu;
131 struct evsel *evsel;
132 struct perf_event_attr attr = {};
133 bool result = true;
134 int ret;
135
136 ret = pfm_get_perf_event_encoding(name, PFM_PLM0|PFM_PLM3,
137 &attr, NULL, NULL);
138 if (ret != PFM_SUCCESS)
139 return false;
140
141 pmu = perf_pmus__find_by_type((unsigned int)attr.type);
142 evsel = parse_events__add_event(0, &attr, name, /*metric_id=*/NULL, pmu);
143 if (evsel == NULL)
144 return false;
145
146 evsel->is_libpfm_event = true;
147
148 ret = evsel__open(evsel, cpus, threads);
149 if (ret == -EACCES) {
150 /*
151 * This happens if the paranoid value
152 * /proc/sys/kernel/perf_event_paranoid is set to 2
153 * Re-run with exclude_kernel set; we don't do that
154 * by default as some ARM machines do not support it.
155 *
156 */
157 evsel->core.attr.exclude_kernel = 1;
158 ret = evsel__open(evsel, cpus, threads);
159
160 }
161 if (ret < 0)
162 result = false;
163
164 evsel__close(evsel);
165 evsel__delete(evsel);
166
167 return result;
168}
169
170static const char *srcs[PFM_ATTR_CTRL_MAX] = {
171 [PFM_ATTR_CTRL_UNKNOWN] = "???",
172 [PFM_ATTR_CTRL_PMU] = "PMU",
173 [PFM_ATTR_CTRL_PERF_EVENT] = "perf_event",
174};
175
176static void
177print_attr_flags(struct strbuf *buf, const pfm_event_attr_info_t *info)
178{
179 if (info->is_dfl)
180 strbuf_addf(buf, "[default] ");
181
182 if (info->is_precise)
183 strbuf_addf(buf, "[precise] ");
184}
185
186static void
187print_libpfm_event(const struct print_callbacks *print_cb, void *print_state,
188 const pfm_pmu_info_t *pinfo, const pfm_event_info_t *info,
189 struct strbuf *buf)
190{
191 int j, ret;
192 char topic[80], name[80];
193 struct perf_cpu_map *cpus = perf_cpu_map__empty_new(1);
194 struct perf_thread_map *threads = thread_map__new_by_tid(0);
195
196 strbuf_setlen(buf, 0);
197 snprintf(buf: topic, size: sizeof(topic), fmt: "pfm %s", pinfo->name);
198
199 snprintf(buf: name, size: sizeof(name), fmt: "%s::%s", pinfo->name, info->name);
200 strbuf_addf(buf, "Code: 0x%"PRIx64"\n", info->code);
201
202 pfm_for_each_event_attr(j, info) {
203 pfm_event_attr_info_t ainfo;
204 const char *src;
205
206 ainfo.size = sizeof(ainfo);
207 ret = pfm_get_event_attr_info(info->idx, j, PFM_OS_PERF_EVENT_EXT, &ainfo);
208 if (ret != PFM_SUCCESS)
209 continue;
210
211 if (ainfo.ctrl >= PFM_ATTR_CTRL_MAX)
212 ainfo.ctrl = PFM_ATTR_CTRL_UNKNOWN;
213
214 src = srcs[ainfo.ctrl];
215 switch (ainfo.type) {
216 case PFM_ATTR_UMASK: /* Ignore for now */
217 break;
218 case PFM_ATTR_MOD_BOOL:
219 strbuf_addf(buf, " Modif: %s: [%s] : %s (boolean)\n", src,
220 ainfo.name, ainfo.desc);
221 break;
222 case PFM_ATTR_MOD_INTEGER:
223 strbuf_addf(buf, " Modif: %s: [%s] : %s (integer)\n", src,
224 ainfo.name, ainfo.desc);
225 break;
226 case PFM_ATTR_NONE:
227 case PFM_ATTR_RAW_UMASK:
228 case PFM_ATTR_MAX:
229 default:
230 strbuf_addf(buf, " Attr: %s: [%s] : %s\n", src,
231 ainfo.name, ainfo.desc);
232 }
233 }
234
235 if (is_libpfm_event_supported(name, cpus, threads)) {
236 print_cb->print_event(print_state, pinfo->name, topic,
237 name, info->equiv,
238 /*scale_unit=*/NULL,
239 /*deprecated=*/NULL, "PFM event",
240 info->desc, /*long_desc=*/NULL,
241 /*encoding_desc=*/buf->buf);
242 }
243
244 pfm_for_each_event_attr(j, info) {
245 pfm_event_attr_info_t ainfo;
246 const char *src;
247
248 strbuf_setlen(buf, 0);
249
250 ainfo.size = sizeof(ainfo);
251 ret = pfm_get_event_attr_info(info->idx, j, PFM_OS_PERF_EVENT_EXT, &ainfo);
252 if (ret != PFM_SUCCESS)
253 continue;
254
255 if (ainfo.ctrl >= PFM_ATTR_CTRL_MAX)
256 ainfo.ctrl = PFM_ATTR_CTRL_UNKNOWN;
257
258 src = srcs[ainfo.ctrl];
259 if (ainfo.type == PFM_ATTR_UMASK) {
260 strbuf_addf(buf, "Umask: 0x%02"PRIx64" : %s: ",
261 ainfo.code, src);
262 print_attr_flags(buf, &ainfo);
263 snprintf(name, sizeof(name), "%s::%s:%s",
264 pinfo->name, info->name, ainfo.name);
265
266 if (!is_libpfm_event_supported(name, cpus, threads))
267 continue;
268
269 print_cb->print_event(print_state,
270 pinfo->name,
271 topic,
272 name, /*alias=*/NULL,
273 /*scale_unit=*/NULL,
274 /*deprecated=*/NULL, "PFM event",
275 ainfo.desc, /*long_desc=*/NULL,
276 /*encoding_desc=*/buf->buf);
277 }
278 }
279
280 perf_cpu_map__put(cpus);
281 perf_thread_map__put(threads);
282}
283
284void print_libpfm_events(const struct print_callbacks *print_cb, void *print_state)
285{
286 pfm_event_info_t info;
287 pfm_pmu_info_t pinfo;
288 int p, ret;
289 struct strbuf storage;
290
291 libpfm_initialize();
292
293 /* initialize to zero to indicate ABI version */
294 info.size = sizeof(info);
295 pinfo.size = sizeof(pinfo);
296
297 strbuf_init(&storage, 2048);
298
299 pfm_for_all_pmus(p) {
300 ret = pfm_get_pmu_info(p, &pinfo);
301 if (ret != PFM_SUCCESS)
302 continue;
303
304 /* only print events that are supported by host HW */
305 if (!pinfo.is_present)
306 continue;
307
308 /* handled by perf directly */
309 if (pinfo.pmu == PFM_PMU_PERF_EVENT)
310 continue;
311
312 for (int i = pinfo.first_event; i != -1; i = pfm_get_event_next(i)) {
313 ret = pfm_get_event_info(i, PFM_OS_PERF_EVENT_EXT,
314 &info);
315 if (ret != PFM_SUCCESS)
316 continue;
317
318 print_libpfm_event(print_cb, print_state, &pinfo, &info, &storage);
319 }
320 }
321 strbuf_release(&storage);
322}
323

source code of linux/tools/perf/util/pfm.c