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Linux 4.16-rc1
[cris-mirror.git] / tools / perf / arch / arm / util / cs-etm.c
blobfbfc055d3f4d5cc9ef5e58ead93b98535640569e
1 /*
2 * Copyright(C) 2015 Linaro Limited. All rights reserved.
3 * Author: Mathieu Poirier <mathieu.poirier@linaro.org>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 as published by
7 * the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program. If not, see <http://www.gnu.org/licenses/>.
16 */
17
18 #include <api/fs/fs.h>
19 #include <linux/bitops.h>
20 #include <linux/compiler.h>
21 #include <linux/coresight-pmu.h>
22 #include <linux/kernel.h>
23 #include <linux/log2.h>
24 #include <linux/types.h>
25
26 #include "cs-etm.h"
27 #include "../../perf.h"
28 #include "../../util/auxtrace.h"
29 #include "../../util/cpumap.h"
30 #include "../../util/evlist.h"
31 #include "../../util/evsel.h"
32 #include "../../util/pmu.h"
33 #include "../../util/thread_map.h"
34 #include "../../util/cs-etm.h"
35
36 #include <stdlib.h>
37 #include <sys/stat.h>
38
39 #define ENABLE_SINK_MAX 128
40 #define CS_BUS_DEVICE_PATH "/bus/coresight/devices/"
41
42 struct cs_etm_recording {
43 struct auxtrace_record itr;
44 struct perf_pmu *cs_etm_pmu;
45 struct perf_evlist *evlist;
46 bool snapshot_mode;
47 size_t snapshot_size;
48 };
49
50 static bool cs_etm_is_etmv4(struct auxtrace_record *itr, int cpu);
51
52 static int cs_etm_parse_snapshot_options(struct auxtrace_record *itr,
53 struct record_opts *opts,
54 const char *str)
55 {
56 struct cs_etm_recording *ptr =
57 container_of(itr, struct cs_etm_recording, itr);
58 unsigned long long snapshot_size = 0;
59 char *endptr;
60
61 if (str) {
62 snapshot_size = strtoull(str, &endptr, 0);
63 if (*endptr || snapshot_size > SIZE_MAX)
64 return -1;
65 }
66
67 opts->auxtrace_snapshot_mode = true;
68 opts->auxtrace_snapshot_size = snapshot_size;
69 ptr->snapshot_size = snapshot_size;
70
71 return 0;
72 }
73
74 static int cs_etm_recording_options(struct auxtrace_record *itr,
75 struct perf_evlist *evlist,
76 struct record_opts *opts)
77 {
78 struct cs_etm_recording *ptr =
79 container_of(itr, struct cs_etm_recording, itr);
80 struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
81 struct perf_evsel *evsel, *cs_etm_evsel = NULL;
82 const struct cpu_map *cpus = evlist->cpus;
83 bool privileged = (geteuid() == 0 || perf_event_paranoid() < 0);
84
85 ptr->evlist = evlist;
86 ptr->snapshot_mode = opts->auxtrace_snapshot_mode;
87
88 evlist__for_each_entry(evlist, evsel) {
89 if (evsel->attr.type == cs_etm_pmu->type) {
90 if (cs_etm_evsel) {
91 pr_err("There may be only one %s event\n",
92 CORESIGHT_ETM_PMU_NAME);
93 return -EINVAL;
94 }
95 evsel->attr.freq = 0;
96 evsel->attr.sample_period = 1;
97 cs_etm_evsel = evsel;
98 opts->full_auxtrace = true;
99 }
100 }
101
102 /* no need to continue if at least one event of interest was found */
103 if (!cs_etm_evsel)
104 return 0;
105
106 if (opts->use_clockid) {
107 pr_err("Cannot use clockid (-k option) with %s\n",
108 CORESIGHT_ETM_PMU_NAME);
109 return -EINVAL;
110 }
111
112 /* we are in snapshot mode */
113 if (opts->auxtrace_snapshot_mode) {
114 /*
115 * No size were given to '-S' or '-m,', so go with
116 * the default
117 */
118 if (!opts->auxtrace_snapshot_size &&
119 !opts->auxtrace_mmap_pages) {
120 if (privileged) {
121 opts->auxtrace_mmap_pages = MiB(4) / page_size;
122 } else {
123 opts->auxtrace_mmap_pages =
124 KiB(128) / page_size;
125 if (opts->mmap_pages == UINT_MAX)
126 opts->mmap_pages = KiB(256) / page_size;
127 }
128 } else if (!opts->auxtrace_mmap_pages && !privileged &&
129 opts->mmap_pages == UINT_MAX) {
130 opts->mmap_pages = KiB(256) / page_size;
131 }
132
133 /*
134 * '-m,xyz' was specified but no snapshot size, so make the
135 * snapshot size as big as the auxtrace mmap area.
136 */
137 if (!opts->auxtrace_snapshot_size) {
138 opts->auxtrace_snapshot_size =
139 opts->auxtrace_mmap_pages * (size_t)page_size;
140 }
141
142 /*
143 * -Sxyz was specified but no auxtrace mmap area, so make the
144 * auxtrace mmap area big enough to fit the requested snapshot
145 * size.
146 */
147 if (!opts->auxtrace_mmap_pages) {
148 size_t sz = opts->auxtrace_snapshot_size;
149
150 sz = round_up(sz, page_size) / page_size;
151 opts->auxtrace_mmap_pages = roundup_pow_of_two(sz);
152 }
153
154 /* Snapshost size can't be bigger than the auxtrace area */
155 if (opts->auxtrace_snapshot_size >
156 opts->auxtrace_mmap_pages * (size_t)page_size) {
157 pr_err("Snapshot size %zu must not be greater than AUX area tracing mmap size %zu\n",
158 opts->auxtrace_snapshot_size,
159 opts->auxtrace_mmap_pages * (size_t)page_size);
160 return -EINVAL;
161 }
162
163 /* Something went wrong somewhere - this shouldn't happen */
164 if (!opts->auxtrace_snapshot_size ||
165 !opts->auxtrace_mmap_pages) {
166 pr_err("Failed to calculate default snapshot size and/or AUX area tracing mmap pages\n");
167 return -EINVAL;
168 }
169 }
170
171 /* We are in full trace mode but '-m,xyz' wasn't specified */
172 if (opts->full_auxtrace && !opts->auxtrace_mmap_pages) {
173 if (privileged) {
174 opts->auxtrace_mmap_pages = MiB(4) / page_size;
175 } else {
176 opts->auxtrace_mmap_pages = KiB(128) / page_size;
177 if (opts->mmap_pages == UINT_MAX)
178 opts->mmap_pages = KiB(256) / page_size;
179 }
180
181 }
182
183 /* Validate auxtrace_mmap_pages provided by user */
184 if (opts->auxtrace_mmap_pages) {
185 unsigned int max_page = (KiB(128) / page_size);
186 size_t sz = opts->auxtrace_mmap_pages * (size_t)page_size;
187
188 if (!privileged &&
189 opts->auxtrace_mmap_pages > max_page) {
190 opts->auxtrace_mmap_pages = max_page;
191 pr_err("auxtrace too big, truncating to %d\n",
192 max_page);
193 }
194
195 if (!is_power_of_2(sz)) {
196 pr_err("Invalid mmap size for %s: must be a power of 2\n",
197 CORESIGHT_ETM_PMU_NAME);
198 return -EINVAL;
199 }
200 }
201
202 if (opts->auxtrace_snapshot_mode)
203 pr_debug2("%s snapshot size: %zu\n", CORESIGHT_ETM_PMU_NAME,
204 opts->auxtrace_snapshot_size);
205
206 /*
207 * To obtain the auxtrace buffer file descriptor, the auxtrace
208 * event must come first.
209 */
210 perf_evlist__to_front(evlist, cs_etm_evsel);
211
212 /*
213 * In the case of per-cpu mmaps, we need the CPU on the
214 * AUX event.
215 */
216 if (!cpu_map__empty(cpus))
217 perf_evsel__set_sample_bit(cs_etm_evsel, CPU);
218
219 /* Add dummy event to keep tracking */
220 if (opts->full_auxtrace) {
221 struct perf_evsel *tracking_evsel;
222 int err;
223
224 err = parse_events(evlist, "dummy:u", NULL);
225 if (err)
226 return err;
227
228 tracking_evsel = perf_evlist__last(evlist);
229 perf_evlist__set_tracking_event(evlist, tracking_evsel);
230
231 tracking_evsel->attr.freq = 0;
232 tracking_evsel->attr.sample_period = 1;
233
234 /* In per-cpu case, always need the time of mmap events etc */
235 if (!cpu_map__empty(cpus))
236 perf_evsel__set_sample_bit(tracking_evsel, TIME);
237 }
238
239 return 0;
240 }
241
242 static u64 cs_etm_get_config(struct auxtrace_record *itr)
243 {
244 u64 config = 0;
245 struct cs_etm_recording *ptr =
246 container_of(itr, struct cs_etm_recording, itr);
247 struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
248 struct perf_evlist *evlist = ptr->evlist;
249 struct perf_evsel *evsel;
250
251 evlist__for_each_entry(evlist, evsel) {
252 if (evsel->attr.type == cs_etm_pmu->type) {
253 /*
254 * Variable perf_event_attr::config is assigned to
255 * ETMv3/PTM. The bit fields have been made to match
256 * the ETMv3.5 ETRMCR register specification. See the
257 * PMU_FORMAT_ATTR() declarations in
258 * drivers/hwtracing/coresight/coresight-perf.c for
259 * details.
260 */
261 config = evsel->attr.config;
262 break;
263 }
264 }
265
266 return config;
267 }
268
269 #ifndef BIT
270 #define BIT(N) (1UL << (N))
271 #endif
272
273 static u64 cs_etmv4_get_config(struct auxtrace_record *itr)
274 {
275 u64 config = 0;
276 u64 config_opts = 0;
277
278 /*
279 * The perf event variable config bits represent both
280 * the command line options and register programming
281 * bits in ETMv3/PTM. For ETMv4 we must remap options
282 * to real bits
283 */
284 config_opts = cs_etm_get_config(itr);
285 if (config_opts & BIT(ETM_OPT_CYCACC))
286 config |= BIT(ETM4_CFG_BIT_CYCACC);
287 if (config_opts & BIT(ETM_OPT_TS))
288 config |= BIT(ETM4_CFG_BIT_TS);
289 if (config_opts & BIT(ETM_OPT_RETSTK))
290 config |= BIT(ETM4_CFG_BIT_RETSTK);
291
292 return config;
293 }
294
295 static size_t
296 cs_etm_info_priv_size(struct auxtrace_record *itr __maybe_unused,
297 struct perf_evlist *evlist __maybe_unused)
298 {
299 int i;
300 int etmv3 = 0, etmv4 = 0;
301 const struct cpu_map *cpus = evlist->cpus;
302
303 /* cpu map is not empty, we have specific CPUs to work with */
304 if (!cpu_map__empty(cpus)) {
305 for (i = 0; i < cpu_map__nr(cpus); i++) {
306 if (cs_etm_is_etmv4(itr, cpus->map[i]))
307 etmv4++;
308 else
309 etmv3++;
310 }
311 } else {
312 /* get configuration for all CPUs in the system */
313 for (i = 0; i < cpu__max_cpu(); i++) {
314 if (cs_etm_is_etmv4(itr, i))
315 etmv4++;
316 else
317 etmv3++;
318 }
319 }
320
321 return (CS_ETM_HEADER_SIZE +
322 (etmv4 * CS_ETMV4_PRIV_SIZE) +
323 (etmv3 * CS_ETMV3_PRIV_SIZE));
324 }
325
326 static const char *metadata_etmv3_ro[CS_ETM_PRIV_MAX] = {
327 [CS_ETM_ETMCCER] = "mgmt/etmccer",
328 [CS_ETM_ETMIDR] = "mgmt/etmidr",
329 };
330
331 static const char *metadata_etmv4_ro[CS_ETMV4_PRIV_MAX] = {
332 [CS_ETMV4_TRCIDR0] = "trcidr/trcidr0",
333 [CS_ETMV4_TRCIDR1] = "trcidr/trcidr1",
334 [CS_ETMV4_TRCIDR2] = "trcidr/trcidr2",
335 [CS_ETMV4_TRCIDR8] = "trcidr/trcidr8",
336 [CS_ETMV4_TRCAUTHSTATUS] = "mgmt/trcauthstatus",
337 };
338
339 static bool cs_etm_is_etmv4(struct auxtrace_record *itr, int cpu)
340 {
341 bool ret = false;
342 char path[PATH_MAX];
343 int scan;
344 unsigned int val;
345 struct cs_etm_recording *ptr =
346 container_of(itr, struct cs_etm_recording, itr);
347 struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
348
349 /* Take any of the RO files for ETMv4 and see if it present */
350 snprintf(path, PATH_MAX, "cpu%d/%s",
351 cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR0]);
352 scan = perf_pmu__scan_file(cs_etm_pmu, path, "%x", &val);
353
354 /* The file was read successfully, we have a winner */
355 if (scan == 1)
356 ret = true;
357
358 return ret;
359 }
360
361 static int cs_etm_get_ro(struct perf_pmu *pmu, int cpu, const char *path)
362 {
363 char pmu_path[PATH_MAX];
364 int scan;
365 unsigned int val = 0;
366
367 /* Get RO metadata from sysfs */
368 snprintf(pmu_path, PATH_MAX, "cpu%d/%s", cpu, path);
369
370 scan = perf_pmu__scan_file(pmu, pmu_path, "%x", &val);
371 if (scan != 1)
372 pr_err("%s: error reading: %s\n", __func__, pmu_path);
373
374 return val;
375 }
376
377 static void cs_etm_get_metadata(int cpu, u32 *offset,
378 struct auxtrace_record *itr,
379 struct auxtrace_info_event *info)
380 {
381 u32 increment;
382 u64 magic;
383 struct cs_etm_recording *ptr =
384 container_of(itr, struct cs_etm_recording, itr);
385 struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
386
387 /* first see what kind of tracer this cpu is affined to */
388 if (cs_etm_is_etmv4(itr, cpu)) {
389 magic = __perf_cs_etmv4_magic;
390 /* Get trace configuration register */
391 info->priv[*offset + CS_ETMV4_TRCCONFIGR] =
392 cs_etmv4_get_config(itr);
393 /* Get traceID from the framework */
394 info->priv[*offset + CS_ETMV4_TRCTRACEIDR] =
395 coresight_get_trace_id(cpu);
396 /* Get read-only information from sysFS */
397 info->priv[*offset + CS_ETMV4_TRCIDR0] =
398 cs_etm_get_ro(cs_etm_pmu, cpu,
399 metadata_etmv4_ro[CS_ETMV4_TRCIDR0]);
400 info->priv[*offset + CS_ETMV4_TRCIDR1] =
401 cs_etm_get_ro(cs_etm_pmu, cpu,
402 metadata_etmv4_ro[CS_ETMV4_TRCIDR1]);
403 info->priv[*offset + CS_ETMV4_TRCIDR2] =
404 cs_etm_get_ro(cs_etm_pmu, cpu,
405 metadata_etmv4_ro[CS_ETMV4_TRCIDR2]);
406 info->priv[*offset + CS_ETMV4_TRCIDR8] =
407 cs_etm_get_ro(cs_etm_pmu, cpu,
408 metadata_etmv4_ro[CS_ETMV4_TRCIDR8]);
409 info->priv[*offset + CS_ETMV4_TRCAUTHSTATUS] =
410 cs_etm_get_ro(cs_etm_pmu, cpu,
411 metadata_etmv4_ro
412 [CS_ETMV4_TRCAUTHSTATUS]);
413
414 /* How much space was used */
415 increment = CS_ETMV4_PRIV_MAX;
416 } else {
417 magic = __perf_cs_etmv3_magic;
418 /* Get configuration register */
419 info->priv[*offset + CS_ETM_ETMCR] = cs_etm_get_config(itr);
420 /* Get traceID from the framework */
421 info->priv[*offset + CS_ETM_ETMTRACEIDR] =
422 coresight_get_trace_id(cpu);
423 /* Get read-only information from sysFS */
424 info->priv[*offset + CS_ETM_ETMCCER] =
425 cs_etm_get_ro(cs_etm_pmu, cpu,
426 metadata_etmv3_ro[CS_ETM_ETMCCER]);
427 info->priv[*offset + CS_ETM_ETMIDR] =
428 cs_etm_get_ro(cs_etm_pmu, cpu,
429 metadata_etmv3_ro[CS_ETM_ETMIDR]);
430
431 /* How much space was used */
432 increment = CS_ETM_PRIV_MAX;
433 }
434
435 /* Build generic header portion */
436 info->priv[*offset + CS_ETM_MAGIC] = magic;
437 info->priv[*offset + CS_ETM_CPU] = cpu;
438 /* Where the next CPU entry should start from */
439 *offset += increment;
440 }
441
442 static int cs_etm_info_fill(struct auxtrace_record *itr,
443 struct perf_session *session,
444 struct auxtrace_info_event *info,
445 size_t priv_size)
446 {
447 int i;
448 u32 offset;
449 u64 nr_cpu, type;
450 const struct cpu_map *cpus = session->evlist->cpus;
451 struct cs_etm_recording *ptr =
452 container_of(itr, struct cs_etm_recording, itr);
453 struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
454
455 if (priv_size != cs_etm_info_priv_size(itr, session->evlist))
456 return -EINVAL;
457
458 if (!session->evlist->nr_mmaps)
459 return -EINVAL;
460
461 /* If the cpu_map is empty all CPUs are involved */
462 nr_cpu = cpu_map__empty(cpus) ? cpu__max_cpu() : cpu_map__nr(cpus);
463 /* Get PMU type as dynamically assigned by the core */
464 type = cs_etm_pmu->type;
465
466 /* First fill out the session header */
467 info->type = PERF_AUXTRACE_CS_ETM;
468 info->priv[CS_HEADER_VERSION_0] = 0;
469 info->priv[CS_PMU_TYPE_CPUS] = type << 32;
470 info->priv[CS_PMU_TYPE_CPUS] |= nr_cpu;
471 info->priv[CS_ETM_SNAPSHOT] = ptr->snapshot_mode;
472
473 offset = CS_ETM_SNAPSHOT + 1;
474
475 /* cpu map is not empty, we have specific CPUs to work with */
476 if (!cpu_map__empty(cpus)) {
477 for (i = 0; i < cpu_map__nr(cpus) && offset < priv_size; i++)
478 cs_etm_get_metadata(cpus->map[i], &offset, itr, info);
479 } else {
480 /* get configuration for all CPUs in the system */
481 for (i = 0; i < cpu__max_cpu(); i++)
482 cs_etm_get_metadata(i, &offset, itr, info);
483 }
484
485 return 0;
486 }
487
488 static int cs_etm_find_snapshot(struct auxtrace_record *itr __maybe_unused,
489 int idx, struct auxtrace_mmap *mm,
490 unsigned char *data __maybe_unused,
491 u64 *head, u64 *old)
492 {
493 pr_debug3("%s: mmap index %d old head %zu new head %zu size %zu\n",
494 __func__, idx, (size_t)*old, (size_t)*head, mm->len);
495
496 *old = *head;
497 *head += mm->len;
498
499 return 0;
500 }
501
502 static int cs_etm_snapshot_start(struct auxtrace_record *itr)
503 {
504 struct cs_etm_recording *ptr =
505 container_of(itr, struct cs_etm_recording, itr);
506 struct perf_evsel *evsel;
507
508 evlist__for_each_entry(ptr->evlist, evsel) {
509 if (evsel->attr.type == ptr->cs_etm_pmu->type)
510 return perf_evsel__disable(evsel);
511 }
512 return -EINVAL;
513 }
514
515 static int cs_etm_snapshot_finish(struct auxtrace_record *itr)
516 {
517 struct cs_etm_recording *ptr =
518 container_of(itr, struct cs_etm_recording, itr);
519 struct perf_evsel *evsel;
520
521 evlist__for_each_entry(ptr->evlist, evsel) {
522 if (evsel->attr.type == ptr->cs_etm_pmu->type)
523 return perf_evsel__enable(evsel);
524 }
525 return -EINVAL;
526 }
527
528 static u64 cs_etm_reference(struct auxtrace_record *itr __maybe_unused)
529 {
530 return (((u64) rand() << 0) & 0x00000000FFFFFFFFull) |
531 (((u64) rand() << 32) & 0xFFFFFFFF00000000ull);
532 }
533
534 static void cs_etm_recording_free(struct auxtrace_record *itr)
535 {
536 struct cs_etm_recording *ptr =
537 container_of(itr, struct cs_etm_recording, itr);
538 free(ptr);
539 }
540
541 static int cs_etm_read_finish(struct auxtrace_record *itr, int idx)
542 {
543 struct cs_etm_recording *ptr =
544 container_of(itr, struct cs_etm_recording, itr);
545 struct perf_evsel *evsel;
546
547 evlist__for_each_entry(ptr->evlist, evsel) {
548 if (evsel->attr.type == ptr->cs_etm_pmu->type)
549 return perf_evlist__enable_event_idx(ptr->evlist,
550 evsel, idx);
551 }
552
553 return -EINVAL;
554 }
555
556 struct auxtrace_record *cs_etm_record_init(int *err)
557 {
558 struct perf_pmu *cs_etm_pmu;
559 struct cs_etm_recording *ptr;
560
561 cs_etm_pmu = perf_pmu__find(CORESIGHT_ETM_PMU_NAME);
562
563 if (!cs_etm_pmu) {
564 *err = -EINVAL;
565 goto out;
566 }
567
568 ptr = zalloc(sizeof(struct cs_etm_recording));
569 if (!ptr) {
570 *err = -ENOMEM;
571 goto out;
572 }
573
574 ptr->cs_etm_pmu = cs_etm_pmu;
575 ptr->itr.parse_snapshot_options = cs_etm_parse_snapshot_options;
576 ptr->itr.recording_options = cs_etm_recording_options;
577 ptr->itr.info_priv_size = cs_etm_info_priv_size;
578 ptr->itr.info_fill = cs_etm_info_fill;
579 ptr->itr.find_snapshot = cs_etm_find_snapshot;
580 ptr->itr.snapshot_start = cs_etm_snapshot_start;
581 ptr->itr.snapshot_finish = cs_etm_snapshot_finish;
582 ptr->itr.reference = cs_etm_reference;
583 ptr->itr.free = cs_etm_recording_free;
584 ptr->itr.read_finish = cs_etm_read_finish;
585
586 *err = 0;
587 return &ptr->itr;
588 out:
589 return NULL;
590 }
591
592 static FILE *cs_device__open_file(const char *name)
593 {
594 struct stat st;
595 char path[PATH_MAX];
596 const char *sysfs;
597
598 sysfs = sysfs__mountpoint();
599 if (!sysfs)
600 return NULL;
601
602 snprintf(path, PATH_MAX,
603 "%s" CS_BUS_DEVICE_PATH "%s", sysfs, name);
604
605 if (stat(path, &st) < 0)
606 return NULL;
607
608 return fopen(path, "w");
609
610 }
611
612 static int __printf(2, 3) cs_device__print_file(const char *name, const char *fmt, ...)
613 {
614 va_list args;
615 FILE *file;
616 int ret = -EINVAL;
617
618 va_start(args, fmt);
619 file = cs_device__open_file(name);
620 if (file) {
621 ret = vfprintf(file, fmt, args);
622 fclose(file);
623 }
624 va_end(args);
625 return ret;
626 }
627
628 int cs_etm_set_drv_config(struct perf_evsel_config_term *term)
629 {
630 int ret;
631 char enable_sink[ENABLE_SINK_MAX];
632
633 snprintf(enable_sink, ENABLE_SINK_MAX, "%s/%s",
634 term->val.drv_cfg, "enable_sink");
635
636 ret = cs_device__print_file(enable_sink, "%d", 1);
637 if (ret < 0)
638 return ret;
639
640 return 0;
641 }
CRIS linux kernel tree