1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * intel_pt.c: Intel Processor Trace support
4 * Copyright (c) 2013-2015, Intel Corporation.
5 */
6
7 #include <errno.h>
8 #include <stdbool.h>
9 #include <linux/kernel.h>
10 #include <linux/types.h>
11 #include <linux/bitops.h>
12 #include <linux/log2.h>
13 #include <linux/zalloc.h>
14 #include <linux/err.h>
15 #include <cpuid.h>
16
17 #include "../../../util/session.h"
18 #include "../../../util/event.h"
19 #include "../../../util/evlist.h"
20 #include "../../../util/evsel.h"
21 #include "../../../util/evsel_config.h"
22 #include "../../../util/cpumap.h"
23 #include "../../../util/mmap.h"
24 #include <subcmd/parse-options.h>
25 #include "../../../util/parse-events.h"
26 #include "../../../util/pmus.h"
27 #include "../../../util/debug.h"
28 #include "../../../util/auxtrace.h"
29 #include "../../../util/perf_api_probe.h"
30 #include "../../../util/record.h"
31 #include "../../../util/target.h"
32 #include "../../../util/tsc.h"
33 #include <internal/lib.h> // page_size
34 #include "../../../util/intel-pt.h"
35
36 #define KiB(x) ((x) * 1024)
37 #define MiB(x) ((x) * 1024 * 1024)
38 #define KiB_MASK(x) (KiB(x) - 1)
39 #define MiB_MASK(x) (MiB(x) - 1)
40
41 #define INTEL_PT_PSB_PERIOD_NEAR 256
42
43 struct intel_pt_snapshot_ref {
44 void *ref_buf;
45 size_t ref_offset;
46 bool wrapped;
47 };
48
49 struct intel_pt_recording {
50 struct auxtrace_record itr;
51 struct perf_pmu *intel_pt_pmu;
52 int have_sched_switch;
53 struct evlist *evlist;
54 bool snapshot_mode;
55 bool snapshot_init_done;
56 size_t snapshot_size;
57 size_t snapshot_ref_buf_size;
58 int snapshot_ref_cnt;
59 struct intel_pt_snapshot_ref *snapshot_refs;
60 size_t priv_size;
61 };
62
intel_pt_parse_terms_with_default(struct perf_pmu * pmu,const char * str,u64 * config)63 static int intel_pt_parse_terms_with_default(struct perf_pmu *pmu,
64 const char *str,
65 u64 *config)
66 {
67 struct list_head *terms;
68 struct perf_event_attr attr = { .size = 0, };
69 int err;
70
71 terms = malloc(sizeof(struct list_head));
72 if (!terms)
73 return -ENOMEM;
74
75 INIT_LIST_HEAD(terms);
76
77 err = parse_events_terms(terms, str, /*input=*/ NULL);
78 if (err)
79 goto out_free;
80
81 attr.config = *config;
82 err = perf_pmu__config_terms(pmu, &attr, terms, /*zero=*/true, /*err=*/NULL);
83 if (err)
84 goto out_free;
85
86 *config = attr.config;
87 out_free:
88 parse_events_terms__delete(terms);
89 return err;
90 }
91
intel_pt_parse_terms(struct perf_pmu * pmu,const char * str,u64 * config)92 static int intel_pt_parse_terms(struct perf_pmu *pmu, const char *str, u64 *config)
93 {
94 *config = 0;
95 return intel_pt_parse_terms_with_default(pmu, str, config);
96 }
97
intel_pt_masked_bits(u64 mask,u64 bits)98 static u64 intel_pt_masked_bits(u64 mask, u64 bits)
99 {
100 const u64 top_bit = 1ULL << 63;
101 u64 res = 0;
102 int i;
103
104 for (i = 0; i < 64; i++) {
105 if (mask & top_bit) {
106 res <<= 1;
107 if (bits & top_bit)
108 res |= 1;
109 }
110 mask <<= 1;
111 bits <<= 1;
112 }
113
114 return res;
115 }
116
intel_pt_read_config(struct perf_pmu * intel_pt_pmu,const char * str,struct evlist * evlist,u64 * res)117 static int intel_pt_read_config(struct perf_pmu *intel_pt_pmu, const char *str,
118 struct evlist *evlist, u64 *res)
119 {
120 struct evsel *evsel;
121 u64 mask;
122
123 *res = 0;
124
125 mask = perf_pmu__format_bits(intel_pt_pmu, str);
126 if (!mask)
127 return -EINVAL;
128
129 evlist__for_each_entry(evlist, evsel) {
130 if (evsel->core.attr.type == intel_pt_pmu->type) {
131 *res = intel_pt_masked_bits(mask, evsel->core.attr.config);
132 return 0;
133 }
134 }
135
136 return -EINVAL;
137 }
138
intel_pt_psb_period(struct perf_pmu * intel_pt_pmu,struct evlist * evlist)139 static size_t intel_pt_psb_period(struct perf_pmu *intel_pt_pmu,
140 struct evlist *evlist)
141 {
142 u64 val;
143 int err, topa_multiple_entries;
144 size_t psb_period;
145
146 if (perf_pmu__scan_file(intel_pt_pmu, "caps/topa_multiple_entries",
147 "%d", &topa_multiple_entries) != 1)
148 topa_multiple_entries = 0;
149
150 /*
151 * Use caps/topa_multiple_entries to indicate early hardware that had
152 * extra frequent PSBs.
153 */
154 if (!topa_multiple_entries) {
155 psb_period = 256;
156 goto out;
157 }
158
159 err = intel_pt_read_config(intel_pt_pmu, "psb_period", evlist, &val);
160 if (err)
161 val = 0;
162
163 psb_period = 1 << (val + 11);
164 out:
165 pr_debug2("%s psb_period %zu\n", intel_pt_pmu->name, psb_period);
166 return psb_period;
167 }
168
intel_pt_pick_bit(int bits,int target)169 static int intel_pt_pick_bit(int bits, int target)
170 {
171 int pos, pick = -1;
172
173 for (pos = 0; bits; bits >>= 1, pos++) {
174 if (bits & 1) {
175 if (pos <= target || pick < 0)
176 pick = pos;
177 if (pos >= target)
178 break;
179 }
180 }
181
182 return pick;
183 }
184
intel_pt_default_config(struct perf_pmu * intel_pt_pmu)185 static u64 intel_pt_default_config(struct perf_pmu *intel_pt_pmu)
186 {
187 char buf[256];
188 int mtc, mtc_periods = 0, mtc_period;
189 int psb_cyc, psb_periods, psb_period;
190 int pos = 0;
191 u64 config;
192 char c;
193 int dirfd;
194
195 dirfd = perf_pmu__event_source_devices_fd();
196
197 pos += scnprintf(buf + pos, sizeof(buf) - pos, "tsc");
198
199 if (perf_pmu__scan_file_at(intel_pt_pmu, dirfd, "caps/mtc", "%d",
200 &mtc) != 1)
201 mtc = 1;
202
203 if (mtc) {
204 if (perf_pmu__scan_file_at(intel_pt_pmu, dirfd, "caps/mtc_periods", "%x",
205 &mtc_periods) != 1)
206 mtc_periods = 0;
207 if (mtc_periods) {
208 mtc_period = intel_pt_pick_bit(mtc_periods, 3);
209 pos += scnprintf(buf + pos, sizeof(buf) - pos,
210 ",mtc,mtc_period=%d", mtc_period);
211 }
212 }
213
214 if (perf_pmu__scan_file_at(intel_pt_pmu, dirfd, "caps/psb_cyc", "%d",
215 &psb_cyc) != 1)
216 psb_cyc = 1;
217
218 if (psb_cyc && mtc_periods) {
219 if (perf_pmu__scan_file_at(intel_pt_pmu, dirfd, "caps/psb_periods", "%x",
220 &psb_periods) != 1)
221 psb_periods = 0;
222 if (psb_periods) {
223 psb_period = intel_pt_pick_bit(psb_periods, 3);
224 pos += scnprintf(buf + pos, sizeof(buf) - pos,
225 ",psb_period=%d", psb_period);
226 }
227 }
228
229 if (perf_pmu__scan_file_at(intel_pt_pmu, dirfd, "format/pt", "%c", &c) == 1 &&
230 perf_pmu__scan_file_at(intel_pt_pmu, dirfd, "format/branch", "%c", &c) == 1)
231 pos += scnprintf(buf + pos, sizeof(buf) - pos, ",pt,branch");
232
233 pr_debug2("%s default config: %s\n", intel_pt_pmu->name, buf);
234
235 intel_pt_parse_terms(intel_pt_pmu, buf, &config);
236
237 close(dirfd);
238 return config;
239 }
240
intel_pt_parse_snapshot_options(struct auxtrace_record * itr,struct record_opts * opts,const char * str)241 static int intel_pt_parse_snapshot_options(struct auxtrace_record *itr,
242 struct record_opts *opts,
243 const char *str)
244 {
245 struct intel_pt_recording *ptr =
246 container_of(itr, struct intel_pt_recording, itr);
247 unsigned long long snapshot_size = 0;
248 char *endptr;
249
250 if (str) {
251 snapshot_size = strtoull(str, &endptr, 0);
252 if (*endptr || snapshot_size > SIZE_MAX)
253 return -1;
254 }
255
256 opts->auxtrace_snapshot_mode = true;
257 opts->auxtrace_snapshot_size = snapshot_size;
258
259 ptr->snapshot_size = snapshot_size;
260
261 return 0;
262 }
263
264 struct perf_event_attr *
intel_pt_pmu_default_config(struct perf_pmu * intel_pt_pmu)265 intel_pt_pmu_default_config(struct perf_pmu *intel_pt_pmu)
266 {
267 struct perf_event_attr *attr;
268
269 attr = zalloc(sizeof(struct perf_event_attr));
270 if (!attr)
271 return NULL;
272
273 attr->config = intel_pt_default_config(intel_pt_pmu);
274
275 intel_pt_pmu->selectable = true;
276
277 return attr;
278 }
279
intel_pt_find_filter(struct evlist * evlist,struct perf_pmu * intel_pt_pmu)280 static const char *intel_pt_find_filter(struct evlist *evlist,
281 struct perf_pmu *intel_pt_pmu)
282 {
283 struct evsel *evsel;
284
285 evlist__for_each_entry(evlist, evsel) {
286 if (evsel->core.attr.type == intel_pt_pmu->type)
287 return evsel->filter;
288 }
289
290 return NULL;
291 }
292
intel_pt_filter_bytes(const char * filter)293 static size_t intel_pt_filter_bytes(const char *filter)
294 {
295 size_t len = filter ? strlen(filter) : 0;
296
297 return len ? roundup(len + 1, 8) : 0;
298 }
299
300 static size_t
intel_pt_info_priv_size(struct auxtrace_record * itr,struct evlist * evlist)301 intel_pt_info_priv_size(struct auxtrace_record *itr, struct evlist *evlist)
302 {
303 struct intel_pt_recording *ptr =
304 container_of(itr, struct intel_pt_recording, itr);
305 const char *filter = intel_pt_find_filter(evlist, ptr->intel_pt_pmu);
306
307 ptr->priv_size = (INTEL_PT_AUXTRACE_PRIV_MAX * sizeof(u64)) +
308 intel_pt_filter_bytes(filter);
309 ptr->priv_size += sizeof(u64); /* Cap Event Trace */
310
311 return ptr->priv_size;
312 }
313
intel_pt_tsc_ctc_ratio(u32 * n,u32 * d)314 static void intel_pt_tsc_ctc_ratio(u32 *n, u32 *d)
315 {
316 unsigned int eax = 0, ebx = 0, ecx = 0, edx = 0;
317
318 __get_cpuid(0x15, &eax, &ebx, &ecx, &edx);
319 *n = ebx;
320 *d = eax;
321 }
322
intel_pt_info_fill(struct auxtrace_record * itr,struct perf_session * session,struct perf_record_auxtrace_info * auxtrace_info,size_t priv_size)323 static int intel_pt_info_fill(struct auxtrace_record *itr,
324 struct perf_session *session,
325 struct perf_record_auxtrace_info *auxtrace_info,
326 size_t priv_size)
327 {
328 struct intel_pt_recording *ptr =
329 container_of(itr, struct intel_pt_recording, itr);
330 struct perf_pmu *intel_pt_pmu = ptr->intel_pt_pmu;
331 struct perf_event_mmap_page *pc;
332 struct perf_tsc_conversion tc = { .time_mult = 0, };
333 bool cap_user_time_zero = false, per_cpu_mmaps;
334 u64 tsc_bit, mtc_bit, mtc_freq_bits, cyc_bit, noretcomp_bit;
335 u32 tsc_ctc_ratio_n, tsc_ctc_ratio_d;
336 unsigned long max_non_turbo_ratio;
337 size_t filter_str_len;
338 const char *filter;
339 int event_trace;
340 __u64 *info;
341 int err;
342
343 if (priv_size != ptr->priv_size)
344 return -EINVAL;
345
346 intel_pt_parse_terms(intel_pt_pmu, "tsc", &tsc_bit);
347 intel_pt_parse_terms(intel_pt_pmu, "noretcomp", &noretcomp_bit);
348 intel_pt_parse_terms(intel_pt_pmu, "mtc", &mtc_bit);
349 mtc_freq_bits = perf_pmu__format_bits(intel_pt_pmu, "mtc_period");
350 intel_pt_parse_terms(intel_pt_pmu, "cyc", &cyc_bit);
351
352 intel_pt_tsc_ctc_ratio(&tsc_ctc_ratio_n, &tsc_ctc_ratio_d);
353
354 if (perf_pmu__scan_file(intel_pt_pmu, "max_nonturbo_ratio",
355 "%lu", &max_non_turbo_ratio) != 1)
356 max_non_turbo_ratio = 0;
357 if (perf_pmu__scan_file(intel_pt_pmu, "caps/event_trace",
358 "%d", &event_trace) != 1)
359 event_trace = 0;
360
361 filter = intel_pt_find_filter(session->evlist, ptr->intel_pt_pmu);
362 filter_str_len = filter ? strlen(filter) : 0;
363
364 if (!session->evlist->core.nr_mmaps)
365 return -EINVAL;
366
367 pc = session->evlist->mmap[0].core.base;
368 if (pc) {
369 err = perf_read_tsc_conversion(pc, &tc);
370 if (err) {
371 if (err != -EOPNOTSUPP)
372 return err;
373 } else {
374 cap_user_time_zero = tc.time_mult != 0;
375 }
376 if (!cap_user_time_zero)
377 ui__warning("Intel Processor Trace: TSC not available\n");
378 }
379
380 per_cpu_mmaps = !perf_cpu_map__empty(session->evlist->core.user_requested_cpus);
381
382 auxtrace_info->type = PERF_AUXTRACE_INTEL_PT;
383 auxtrace_info->priv[INTEL_PT_PMU_TYPE] = intel_pt_pmu->type;
384 auxtrace_info->priv[INTEL_PT_TIME_SHIFT] = tc.time_shift;
385 auxtrace_info->priv[INTEL_PT_TIME_MULT] = tc.time_mult;
386 auxtrace_info->priv[INTEL_PT_TIME_ZERO] = tc.time_zero;
387 auxtrace_info->priv[INTEL_PT_CAP_USER_TIME_ZERO] = cap_user_time_zero;
388 auxtrace_info->priv[INTEL_PT_TSC_BIT] = tsc_bit;
389 auxtrace_info->priv[INTEL_PT_NORETCOMP_BIT] = noretcomp_bit;
390 auxtrace_info->priv[INTEL_PT_HAVE_SCHED_SWITCH] = ptr->have_sched_switch;
391 auxtrace_info->priv[INTEL_PT_SNAPSHOT_MODE] = ptr->snapshot_mode;
392 auxtrace_info->priv[INTEL_PT_PER_CPU_MMAPS] = per_cpu_mmaps;
393 auxtrace_info->priv[INTEL_PT_MTC_BIT] = mtc_bit;
394 auxtrace_info->priv[INTEL_PT_MTC_FREQ_BITS] = mtc_freq_bits;
395 auxtrace_info->priv[INTEL_PT_TSC_CTC_N] = tsc_ctc_ratio_n;
396 auxtrace_info->priv[INTEL_PT_TSC_CTC_D] = tsc_ctc_ratio_d;
397 auxtrace_info->priv[INTEL_PT_CYC_BIT] = cyc_bit;
398 auxtrace_info->priv[INTEL_PT_MAX_NONTURBO_RATIO] = max_non_turbo_ratio;
399 auxtrace_info->priv[INTEL_PT_FILTER_STR_LEN] = filter_str_len;
400
401 info = &auxtrace_info->priv[INTEL_PT_FILTER_STR_LEN] + 1;
402
403 if (filter_str_len) {
404 size_t len = intel_pt_filter_bytes(filter);
405
406 strncpy((char *)info, filter, len);
407 info += len >> 3;
408 }
409
410 *info++ = event_trace;
411
412 return 0;
413 }
414
415 #ifdef HAVE_LIBTRACEEVENT
intel_pt_track_switches(struct evlist * evlist)416 static int intel_pt_track_switches(struct evlist *evlist)
417 {
418 const char *sched_switch = "sched:sched_switch";
419 struct evsel *evsel;
420 int err;
421
422 if (!evlist__can_select_event(evlist, sched_switch))
423 return -EPERM;
424
425 evsel = evlist__add_sched_switch(evlist, true);
426 if (IS_ERR(evsel)) {
427 err = PTR_ERR(evsel);
428 pr_debug2("%s: failed to create %s, error = %d\n",
429 __func__, sched_switch, err);
430 return err;
431 }
432
433 evsel->immediate = true;
434
435 return 0;
436 }
437 #endif
438
intel_pt_valid_str(char * str,size_t len,u64 valid)439 static void intel_pt_valid_str(char *str, size_t len, u64 valid)
440 {
441 unsigned int val, last = 0, state = 1;
442 int p = 0;
443
444 str[0] = '\0';
445
446 for (val = 0; val <= 64; val++, valid >>= 1) {
447 if (valid & 1) {
448 last = val;
449 switch (state) {
450 case 0:
451 p += scnprintf(str + p, len - p, ",");
452 /* Fall through */
453 case 1:
454 p += scnprintf(str + p, len - p, "%u", val);
455 state = 2;
456 break;
457 case 2:
458 state = 3;
459 break;
460 case 3:
461 state = 4;
462 break;
463 default:
464 break;
465 }
466 } else {
467 switch (state) {
468 case 3:
469 p += scnprintf(str + p, len - p, ",%u", last);
470 state = 0;
471 break;
472 case 4:
473 p += scnprintf(str + p, len - p, "-%u", last);
474 state = 0;
475 break;
476 default:
477 break;
478 }
479 if (state != 1)
480 state = 0;
481 }
482 }
483 }
484
intel_pt_val_config_term(struct perf_pmu * intel_pt_pmu,int dirfd,const char * caps,const char * name,const char * supported,u64 config)485 static int intel_pt_val_config_term(struct perf_pmu *intel_pt_pmu, int dirfd,
486 const char *caps, const char *name,
487 const char *supported, u64 config)
488 {
489 char valid_str[256];
490 unsigned int shift;
491 unsigned long long valid;
492 u64 bits;
493 int ok;
494
495 if (perf_pmu__scan_file_at(intel_pt_pmu, dirfd, caps, "%llx", &valid) != 1)
496 valid = 0;
497
498 if (supported &&
499 perf_pmu__scan_file_at(intel_pt_pmu, dirfd, supported, "%d", &ok) == 1 && !ok)
500 valid = 0;
501
502 valid |= 1;
503
504 bits = perf_pmu__format_bits(intel_pt_pmu, name);
505
506 config &= bits;
507
508 for (shift = 0; bits && !(bits & 1); shift++)
509 bits >>= 1;
510
511 config >>= shift;
512
513 if (config > 63)
514 goto out_err;
515
516 if (valid & (1 << config))
517 return 0;
518 out_err:
519 intel_pt_valid_str(valid_str, sizeof(valid_str), valid);
520 pr_err("Invalid %s for %s. Valid values are: %s\n",
521 name, INTEL_PT_PMU_NAME, valid_str);
522 return -EINVAL;
523 }
524
intel_pt_validate_config(struct perf_pmu * intel_pt_pmu,struct evsel * evsel)525 static int intel_pt_validate_config(struct perf_pmu *intel_pt_pmu,
526 struct evsel *evsel)
527 {
528 int err, dirfd;
529 char c;
530
531 if (!evsel)
532 return 0;
533
534 dirfd = perf_pmu__event_source_devices_fd();
535 if (dirfd < 0)
536 return dirfd;
537
538 /*
539 * If supported, force pass-through config term (pt=1) even if user
540 * sets pt=0, which avoids senseless kernel errors.
541 */
542 if (perf_pmu__scan_file_at(intel_pt_pmu, dirfd, "format/pt", "%c", &c) == 1 &&
543 !(evsel->core.attr.config & 1)) {
544 pr_warning("pt=0 doesn't make sense, forcing pt=1\n");
545 evsel->core.attr.config |= 1;
546 }
547
548 err = intel_pt_val_config_term(intel_pt_pmu, dirfd, "caps/cycle_thresholds",
549 "cyc_thresh", "caps/psb_cyc",
550 evsel->core.attr.config);
551 if (err)
552 goto out;
553
554 err = intel_pt_val_config_term(intel_pt_pmu, dirfd, "caps/mtc_periods",
555 "mtc_period", "caps/mtc",
556 evsel->core.attr.config);
557 if (err)
558 goto out;
559
560 err = intel_pt_val_config_term(intel_pt_pmu, dirfd, "caps/psb_periods",
561 "psb_period", "caps/psb_cyc",
562 evsel->core.attr.config);
563
564 out:
565 close(dirfd);
566 return err;
567 }
568
intel_pt_min_max_sample_sz(struct evlist * evlist,size_t * min_sz,size_t * max_sz)569 static void intel_pt_min_max_sample_sz(struct evlist *evlist,
570 size_t *min_sz, size_t *max_sz)
571 {
572 struct evsel *evsel;
573
574 evlist__for_each_entry(evlist, evsel) {
575 size_t sz = evsel->core.attr.aux_sample_size;
576
577 if (!sz)
578 continue;
579 if (min_sz && (sz < *min_sz || !*min_sz))
580 *min_sz = sz;
581 if (max_sz && sz > *max_sz)
582 *max_sz = sz;
583 }
584 }
585
586 /*
587 * Currently, there is not enough information to disambiguate different PEBS
588 * events, so only allow one.
589 */
intel_pt_too_many_aux_output(struct evlist * evlist)590 static bool intel_pt_too_many_aux_output(struct evlist *evlist)
591 {
592 struct evsel *evsel;
593 int aux_output_cnt = 0;
594
595 evlist__for_each_entry(evlist, evsel)
596 aux_output_cnt += !!evsel->core.attr.aux_output;
597
598 if (aux_output_cnt > 1) {
599 pr_err(INTEL_PT_PMU_NAME " supports at most one event with aux-output\n");
600 return true;
601 }
602
603 return false;
604 }
605
intel_pt_recording_options(struct auxtrace_record * itr,struct evlist * evlist,struct record_opts * opts)606 static int intel_pt_recording_options(struct auxtrace_record *itr,
607 struct evlist *evlist,
608 struct record_opts *opts)
609 {
610 struct intel_pt_recording *ptr =
611 container_of(itr, struct intel_pt_recording, itr);
612 struct perf_pmu *intel_pt_pmu = ptr->intel_pt_pmu;
613 bool have_timing_info, need_immediate = false;
614 struct evsel *evsel, *intel_pt_evsel = NULL;
615 const struct perf_cpu_map *cpus = evlist->core.user_requested_cpus;
616 bool privileged = perf_event_paranoid_check(-1);
617 u64 tsc_bit;
618 int err;
619
620 ptr->evlist = evlist;
621 ptr->snapshot_mode = opts->auxtrace_snapshot_mode;
622
623 evlist__for_each_entry(evlist, evsel) {
624 if (evsel->core.attr.type == intel_pt_pmu->type) {
625 if (intel_pt_evsel) {
626 pr_err("There may be only one " INTEL_PT_PMU_NAME " event\n");
627 return -EINVAL;
628 }
629 evsel->core.attr.freq = 0;
630 evsel->core.attr.sample_period = 1;
631 evsel->no_aux_samples = true;
632 evsel->needs_auxtrace_mmap = true;
633 intel_pt_evsel = evsel;
634 opts->full_auxtrace = true;
635 }
636 }
637
638 if (opts->auxtrace_snapshot_mode && !opts->full_auxtrace) {
639 pr_err("Snapshot mode (-S option) requires " INTEL_PT_PMU_NAME " PMU event (-e " INTEL_PT_PMU_NAME ")\n");
640 return -EINVAL;
641 }
642
643 if (opts->auxtrace_snapshot_mode && opts->auxtrace_sample_mode) {
644 pr_err("Snapshot mode (" INTEL_PT_PMU_NAME " PMU) and sample trace cannot be used together\n");
645 return -EINVAL;
646 }
647
648 if (opts->use_clockid) {
649 pr_err("Cannot use clockid (-k option) with " INTEL_PT_PMU_NAME "\n");
650 return -EINVAL;
651 }
652
653 if (intel_pt_too_many_aux_output(evlist))
654 return -EINVAL;
655
656 if (!opts->full_auxtrace)
657 return 0;
658
659 if (opts->auxtrace_sample_mode)
660 evsel__set_config_if_unset(intel_pt_pmu, intel_pt_evsel,
661 "psb_period", 0);
662
663 err = intel_pt_validate_config(intel_pt_pmu, intel_pt_evsel);
664 if (err)
665 return err;
666
667 /* Set default sizes for snapshot mode */
668 if (opts->auxtrace_snapshot_mode) {
669 size_t psb_period = intel_pt_psb_period(intel_pt_pmu, evlist);
670
671 if (!opts->auxtrace_snapshot_size && !opts->auxtrace_mmap_pages) {
672 if (privileged) {
673 opts->auxtrace_mmap_pages = MiB(4) / page_size;
674 } else {
675 opts->auxtrace_mmap_pages = KiB(128) / page_size;
676 if (opts->mmap_pages == UINT_MAX)
677 opts->mmap_pages = KiB(256) / page_size;
678 }
679 } else if (!opts->auxtrace_mmap_pages && !privileged &&
680 opts->mmap_pages == UINT_MAX) {
681 opts->mmap_pages = KiB(256) / page_size;
682 }
683 if (!opts->auxtrace_snapshot_size)
684 opts->auxtrace_snapshot_size =
685 opts->auxtrace_mmap_pages * (size_t)page_size;
686 if (!opts->auxtrace_mmap_pages) {
687 size_t sz = opts->auxtrace_snapshot_size;
688
689 sz = round_up(sz, page_size) / page_size;
690 opts->auxtrace_mmap_pages = roundup_pow_of_two(sz);
691 }
692 if (opts->auxtrace_snapshot_size >
693 opts->auxtrace_mmap_pages * (size_t)page_size) {
694 pr_err("Snapshot size %zu must not be greater than AUX area tracing mmap size %zu\n",
695 opts->auxtrace_snapshot_size,
696 opts->auxtrace_mmap_pages * (size_t)page_size);
697 return -EINVAL;
698 }
699 if (!opts->auxtrace_snapshot_size || !opts->auxtrace_mmap_pages) {
700 pr_err("Failed to calculate default snapshot size and/or AUX area tracing mmap pages\n");
701 return -EINVAL;
702 }
703 pr_debug2("Intel PT snapshot size: %zu\n",
704 opts->auxtrace_snapshot_size);
705 if (psb_period &&
706 opts->auxtrace_snapshot_size <= psb_period +
707 INTEL_PT_PSB_PERIOD_NEAR)
708 ui__warning("Intel PT snapshot size (%zu) may be too small for PSB period (%zu)\n",
709 opts->auxtrace_snapshot_size, psb_period);
710 }
711
712 /* Set default sizes for sample mode */
713 if (opts->auxtrace_sample_mode) {
714 size_t psb_period = intel_pt_psb_period(intel_pt_pmu, evlist);
715 size_t min_sz = 0, max_sz = 0;
716
717 intel_pt_min_max_sample_sz(evlist, &min_sz, &max_sz);
718 if (!opts->auxtrace_mmap_pages && !privileged &&
719 opts->mmap_pages == UINT_MAX)
720 opts->mmap_pages = KiB(256) / page_size;
721 if (!opts->auxtrace_mmap_pages) {
722 size_t sz = round_up(max_sz, page_size) / page_size;
723
724 opts->auxtrace_mmap_pages = roundup_pow_of_two(sz);
725 }
726 if (max_sz > opts->auxtrace_mmap_pages * (size_t)page_size) {
727 pr_err("Sample size %zu must not be greater than AUX area tracing mmap size %zu\n",
728 max_sz,
729 opts->auxtrace_mmap_pages * (size_t)page_size);
730 return -EINVAL;
731 }
732 pr_debug2("Intel PT min. sample size: %zu max. sample size: %zu\n",
733 min_sz, max_sz);
734 if (psb_period &&
735 min_sz <= psb_period + INTEL_PT_PSB_PERIOD_NEAR)
736 ui__warning("Intel PT sample size (%zu) may be too small for PSB period (%zu)\n",
737 min_sz, psb_period);
738 }
739
740 /* Set default sizes for full trace mode */
741 if (opts->full_auxtrace && !opts->auxtrace_mmap_pages) {
742 if (privileged) {
743 opts->auxtrace_mmap_pages = MiB(4) / page_size;
744 } else {
745 opts->auxtrace_mmap_pages = KiB(128) / page_size;
746 if (opts->mmap_pages == UINT_MAX)
747 opts->mmap_pages = KiB(256) / page_size;
748 }
749 }
750
751 /* Validate auxtrace_mmap_pages */
752 if (opts->auxtrace_mmap_pages) {
753 size_t sz = opts->auxtrace_mmap_pages * (size_t)page_size;
754 size_t min_sz;
755
756 if (opts->auxtrace_snapshot_mode || opts->auxtrace_sample_mode)
757 min_sz = KiB(4);
758 else
759 min_sz = KiB(8);
760
761 if (sz < min_sz || !is_power_of_2(sz)) {
762 pr_err("Invalid mmap size for Intel Processor Trace: must be at least %zuKiB and a power of 2\n",
763 min_sz / 1024);
764 return -EINVAL;
765 }
766 }
767
768 if (!opts->auxtrace_snapshot_mode && !opts->auxtrace_sample_mode) {
769 u32 aux_watermark = opts->auxtrace_mmap_pages * page_size / 4;
770
771 intel_pt_evsel->core.attr.aux_watermark = aux_watermark;
772 }
773
774 intel_pt_parse_terms(intel_pt_pmu, "tsc", &tsc_bit);
775
776 if (opts->full_auxtrace && (intel_pt_evsel->core.attr.config & tsc_bit))
777 have_timing_info = true;
778 else
779 have_timing_info = false;
780
781 /*
782 * Per-cpu recording needs sched_switch events to distinguish different
783 * threads.
784 */
785 if (have_timing_info && !perf_cpu_map__empty(cpus) &&
786 !record_opts__no_switch_events(opts)) {
787 if (perf_can_record_switch_events()) {
788 bool cpu_wide = !target__none(&opts->target) &&
789 !target__has_task(&opts->target);
790
791 if (!cpu_wide && perf_can_record_cpu_wide()) {
792 struct evsel *switch_evsel;
793
794 switch_evsel = evlist__add_dummy_on_all_cpus(evlist);
795 if (!switch_evsel)
796 return -ENOMEM;
797
798 switch_evsel->core.attr.context_switch = 1;
799 switch_evsel->immediate = true;
800
801 evsel__set_sample_bit(switch_evsel, TID);
802 evsel__set_sample_bit(switch_evsel, TIME);
803 evsel__set_sample_bit(switch_evsel, CPU);
804 evsel__reset_sample_bit(switch_evsel, BRANCH_STACK);
805
806 opts->record_switch_events = false;
807 ptr->have_sched_switch = 3;
808 } else {
809 opts->record_switch_events = true;
810 need_immediate = true;
811 if (cpu_wide)
812 ptr->have_sched_switch = 3;
813 else
814 ptr->have_sched_switch = 2;
815 }
816 } else {
817 #ifdef HAVE_LIBTRACEEVENT
818 err = intel_pt_track_switches(evlist);
819 if (err == -EPERM)
820 pr_debug2("Unable to select sched:sched_switch\n");
821 else if (err)
822 return err;
823 else
824 ptr->have_sched_switch = 1;
825 #endif
826 }
827 }
828
829 if (have_timing_info && !intel_pt_evsel->core.attr.exclude_kernel &&
830 perf_can_record_text_poke_events() && perf_can_record_cpu_wide())
831 opts->text_poke = true;
832
833 if (intel_pt_evsel) {
834 /*
835 * To obtain the auxtrace buffer file descriptor, the auxtrace
836 * event must come first.
837 */
838 evlist__to_front(evlist, intel_pt_evsel);
839 /*
840 * In the case of per-cpu mmaps, we need the CPU on the
841 * AUX event.
842 */
843 if (!perf_cpu_map__empty(cpus))
844 evsel__set_sample_bit(intel_pt_evsel, CPU);
845 }
846
847 /* Add dummy event to keep tracking */
848 if (opts->full_auxtrace) {
849 bool need_system_wide_tracking;
850 struct evsel *tracking_evsel;
851
852 /*
853 * User space tasks can migrate between CPUs, so when tracing
854 * selected CPUs, sideband for all CPUs is still needed.
855 */
856 need_system_wide_tracking = opts->target.cpu_list &&
857 !intel_pt_evsel->core.attr.exclude_user;
858
859 tracking_evsel = evlist__add_aux_dummy(evlist, need_system_wide_tracking);
860 if (!tracking_evsel)
861 return -ENOMEM;
862
863 evlist__set_tracking_event(evlist, tracking_evsel);
864
865 if (need_immediate)
866 tracking_evsel->immediate = true;
867
868 /* In per-cpu case, always need the time of mmap events etc */
869 if (!perf_cpu_map__empty(cpus)) {
870 evsel__set_sample_bit(tracking_evsel, TIME);
871 /* And the CPU for switch events */
872 evsel__set_sample_bit(tracking_evsel, CPU);
873 }
874 evsel__reset_sample_bit(tracking_evsel, BRANCH_STACK);
875 }
876
877 /*
878 * Warn the user when we do not have enough information to decode i.e.
879 * per-cpu with no sched_switch (except workload-only).
880 */
881 if (!ptr->have_sched_switch && !perf_cpu_map__empty(cpus) &&
882 !target__none(&opts->target) &&
883 !intel_pt_evsel->core.attr.exclude_user)
884 ui__warning("Intel Processor Trace decoding will not be possible except for kernel tracing!\n");
885
886 return 0;
887 }
888
intel_pt_snapshot_start(struct auxtrace_record * itr)889 static int intel_pt_snapshot_start(struct auxtrace_record *itr)
890 {
891 struct intel_pt_recording *ptr =
892 container_of(itr, struct intel_pt_recording, itr);
893 struct evsel *evsel;
894
895 evlist__for_each_entry(ptr->evlist, evsel) {
896 if (evsel->core.attr.type == ptr->intel_pt_pmu->type)
897 return evsel__disable(evsel);
898 }
899 return -EINVAL;
900 }
901
intel_pt_snapshot_finish(struct auxtrace_record * itr)902 static int intel_pt_snapshot_finish(struct auxtrace_record *itr)
903 {
904 struct intel_pt_recording *ptr =
905 container_of(itr, struct intel_pt_recording, itr);
906 struct evsel *evsel;
907
908 evlist__for_each_entry(ptr->evlist, evsel) {
909 if (evsel->core.attr.type == ptr->intel_pt_pmu->type)
910 return evsel__enable(evsel);
911 }
912 return -EINVAL;
913 }
914
intel_pt_alloc_snapshot_refs(struct intel_pt_recording * ptr,int idx)915 static int intel_pt_alloc_snapshot_refs(struct intel_pt_recording *ptr, int idx)
916 {
917 const size_t sz = sizeof(struct intel_pt_snapshot_ref);
918 int cnt = ptr->snapshot_ref_cnt, new_cnt = cnt * 2;
919 struct intel_pt_snapshot_ref *refs;
920
921 if (!new_cnt)
922 new_cnt = 16;
923
924 while (new_cnt <= idx)
925 new_cnt *= 2;
926
927 refs = calloc(new_cnt, sz);
928 if (!refs)
929 return -ENOMEM;
930
931 memcpy(refs, ptr->snapshot_refs, cnt * sz);
932
933 ptr->snapshot_refs = refs;
934 ptr->snapshot_ref_cnt = new_cnt;
935
936 return 0;
937 }
938
intel_pt_free_snapshot_refs(struct intel_pt_recording * ptr)939 static void intel_pt_free_snapshot_refs(struct intel_pt_recording *ptr)
940 {
941 int i;
942
943 for (i = 0; i < ptr->snapshot_ref_cnt; i++)
944 zfree(&ptr->snapshot_refs[i].ref_buf);
945 zfree(&ptr->snapshot_refs);
946 }
947
intel_pt_recording_free(struct auxtrace_record * itr)948 static void intel_pt_recording_free(struct auxtrace_record *itr)
949 {
950 struct intel_pt_recording *ptr =
951 container_of(itr, struct intel_pt_recording, itr);
952
953 intel_pt_free_snapshot_refs(ptr);
954 free(ptr);
955 }
956
intel_pt_alloc_snapshot_ref(struct intel_pt_recording * ptr,int idx,size_t snapshot_buf_size)957 static int intel_pt_alloc_snapshot_ref(struct intel_pt_recording *ptr, int idx,
958 size_t snapshot_buf_size)
959 {
960 size_t ref_buf_size = ptr->snapshot_ref_buf_size;
961 void *ref_buf;
962
963 ref_buf = zalloc(ref_buf_size);
964 if (!ref_buf)
965 return -ENOMEM;
966
967 ptr->snapshot_refs[idx].ref_buf = ref_buf;
968 ptr->snapshot_refs[idx].ref_offset = snapshot_buf_size - ref_buf_size;
969
970 return 0;
971 }
972
intel_pt_snapshot_ref_buf_size(struct intel_pt_recording * ptr,size_t snapshot_buf_size)973 static size_t intel_pt_snapshot_ref_buf_size(struct intel_pt_recording *ptr,
974 size_t snapshot_buf_size)
975 {
976 const size_t max_size = 256 * 1024;
977 size_t buf_size = 0, psb_period;
978
979 if (ptr->snapshot_size <= 64 * 1024)
980 return 0;
981
982 psb_period = intel_pt_psb_period(ptr->intel_pt_pmu, ptr->evlist);
983 if (psb_period)
984 buf_size = psb_period * 2;
985
986 if (!buf_size || buf_size > max_size)
987 buf_size = max_size;
988
989 if (buf_size >= snapshot_buf_size)
990 return 0;
991
992 if (buf_size >= ptr->snapshot_size / 2)
993 return 0;
994
995 return buf_size;
996 }
997
intel_pt_snapshot_init(struct intel_pt_recording * ptr,size_t snapshot_buf_size)998 static int intel_pt_snapshot_init(struct intel_pt_recording *ptr,
999 size_t snapshot_buf_size)
1000 {
1001 if (ptr->snapshot_init_done)
1002 return 0;
1003
1004 ptr->snapshot_init_done = true;
1005
1006 ptr->snapshot_ref_buf_size = intel_pt_snapshot_ref_buf_size(ptr,
1007 snapshot_buf_size);
1008
1009 return 0;
1010 }
1011
1012 /**
1013 * intel_pt_compare_buffers - compare bytes in a buffer to a circular buffer.
1014 * @buf1: first buffer
1015 * @compare_size: number of bytes to compare
1016 * @buf2: second buffer (a circular buffer)
1017 * @offs2: offset in second buffer
1018 * @buf2_size: size of second buffer
1019 *
1020 * The comparison allows for the possibility that the bytes to compare in the
1021 * circular buffer are not contiguous. It is assumed that @compare_size <=
1022 * @buf2_size. This function returns %false if the bytes are identical, %true
1023 * otherwise.
1024 */
intel_pt_compare_buffers(void * buf1,size_t compare_size,void * buf2,size_t offs2,size_t buf2_size)1025 static bool intel_pt_compare_buffers(void *buf1, size_t compare_size,
1026 void *buf2, size_t offs2, size_t buf2_size)
1027 {
1028 size_t end2 = offs2 + compare_size, part_size;
1029
1030 if (end2 <= buf2_size)
1031 return memcmp(buf1, buf2 + offs2, compare_size);
1032
1033 part_size = end2 - buf2_size;
1034 if (memcmp(buf1, buf2 + offs2, part_size))
1035 return true;
1036
1037 compare_size -= part_size;
1038
1039 return memcmp(buf1 + part_size, buf2, compare_size);
1040 }
1041
intel_pt_compare_ref(void * ref_buf,size_t ref_offset,size_t ref_size,size_t buf_size,void * data,size_t head)1042 static bool intel_pt_compare_ref(void *ref_buf, size_t ref_offset,
1043 size_t ref_size, size_t buf_size,
1044 void *data, size_t head)
1045 {
1046 size_t ref_end = ref_offset + ref_size;
1047
1048 if (ref_end > buf_size) {
1049 if (head > ref_offset || head < ref_end - buf_size)
1050 return true;
1051 } else if (head > ref_offset && head < ref_end) {
1052 return true;
1053 }
1054
1055 return intel_pt_compare_buffers(ref_buf, ref_size, data, ref_offset,
1056 buf_size);
1057 }
1058
intel_pt_copy_ref(void * ref_buf,size_t ref_size,size_t buf_size,void * data,size_t head)1059 static void intel_pt_copy_ref(void *ref_buf, size_t ref_size, size_t buf_size,
1060 void *data, size_t head)
1061 {
1062 if (head >= ref_size) {
1063 memcpy(ref_buf, data + head - ref_size, ref_size);
1064 } else {
1065 memcpy(ref_buf, data, head);
1066 ref_size -= head;
1067 memcpy(ref_buf + head, data + buf_size - ref_size, ref_size);
1068 }
1069 }
1070
intel_pt_wrapped(struct intel_pt_recording * ptr,int idx,struct auxtrace_mmap * mm,unsigned char * data,u64 head)1071 static bool intel_pt_wrapped(struct intel_pt_recording *ptr, int idx,
1072 struct auxtrace_mmap *mm, unsigned char *data,
1073 u64 head)
1074 {
1075 struct intel_pt_snapshot_ref *ref = &ptr->snapshot_refs[idx];
1076 bool wrapped;
1077
1078 wrapped = intel_pt_compare_ref(ref->ref_buf, ref->ref_offset,
1079 ptr->snapshot_ref_buf_size, mm->len,
1080 data, head);
1081
1082 intel_pt_copy_ref(ref->ref_buf, ptr->snapshot_ref_buf_size, mm->len,
1083 data, head);
1084
1085 return wrapped;
1086 }
1087
intel_pt_first_wrap(u64 * data,size_t buf_size)1088 static bool intel_pt_first_wrap(u64 *data, size_t buf_size)
1089 {
1090 int i, a, b;
1091
1092 b = buf_size >> 3;
1093 a = b - 512;
1094 if (a < 0)
1095 a = 0;
1096
1097 for (i = a; i < b; i++) {
1098 if (data[i])
1099 return true;
1100 }
1101
1102 return false;
1103 }
1104
intel_pt_find_snapshot(struct auxtrace_record * itr,int idx,struct auxtrace_mmap * mm,unsigned char * data,u64 * head,u64 * old)1105 static int intel_pt_find_snapshot(struct auxtrace_record *itr, int idx,
1106 struct auxtrace_mmap *mm, unsigned char *data,
1107 u64 *head, u64 *old)
1108 {
1109 struct intel_pt_recording *ptr =
1110 container_of(itr, struct intel_pt_recording, itr);
1111 bool wrapped;
1112 int err;
1113
1114 pr_debug3("%s: mmap index %d old head %zu new head %zu\n",
1115 __func__, idx, (size_t)*old, (size_t)*head);
1116
1117 err = intel_pt_snapshot_init(ptr, mm->len);
1118 if (err)
1119 goto out_err;
1120
1121 if (idx >= ptr->snapshot_ref_cnt) {
1122 err = intel_pt_alloc_snapshot_refs(ptr, idx);
1123 if (err)
1124 goto out_err;
1125 }
1126
1127 if (ptr->snapshot_ref_buf_size) {
1128 if (!ptr->snapshot_refs[idx].ref_buf) {
1129 err = intel_pt_alloc_snapshot_ref(ptr, idx, mm->len);
1130 if (err)
1131 goto out_err;
1132 }
1133 wrapped = intel_pt_wrapped(ptr, idx, mm, data, *head);
1134 } else {
1135 wrapped = ptr->snapshot_refs[idx].wrapped;
1136 if (!wrapped && intel_pt_first_wrap((u64 *)data, mm->len)) {
1137 ptr->snapshot_refs[idx].wrapped = true;
1138 wrapped = true;
1139 }
1140 }
1141
1142 /*
1143 * In full trace mode 'head' continually increases. However in snapshot
1144 * mode 'head' is an offset within the buffer. Here 'old' and 'head'
1145 * are adjusted to match the full trace case which expects that 'old' is
1146 * always less than 'head'.
1147 */
1148 if (wrapped) {
1149 *old = *head;
1150 *head += mm->len;
1151 } else {
1152 if (mm->mask)
1153 *old &= mm->mask;
1154 else
1155 *old %= mm->len;
1156 if (*old > *head)
1157 *head += mm->len;
1158 }
1159
1160 pr_debug3("%s: wrap-around %sdetected, adjusted old head %zu adjusted new head %zu\n",
1161 __func__, wrapped ? "" : "not ", (size_t)*old, (size_t)*head);
1162
1163 return 0;
1164
1165 out_err:
1166 pr_err("%s: failed, error %d\n", __func__, err);
1167 return err;
1168 }
1169
intel_pt_reference(struct auxtrace_record * itr __maybe_unused)1170 static u64 intel_pt_reference(struct auxtrace_record *itr __maybe_unused)
1171 {
1172 return rdtsc();
1173 }
1174
intel_pt_recording_init(int * err)1175 struct auxtrace_record *intel_pt_recording_init(int *err)
1176 {
1177 struct perf_pmu *intel_pt_pmu = perf_pmus__find(INTEL_PT_PMU_NAME);
1178 struct intel_pt_recording *ptr;
1179
1180 if (!intel_pt_pmu)
1181 return NULL;
1182
1183 if (setenv("JITDUMP_USE_ARCH_TIMESTAMP", "1", 1)) {
1184 *err = -errno;
1185 return NULL;
1186 }
1187
1188 ptr = zalloc(sizeof(struct intel_pt_recording));
1189 if (!ptr) {
1190 *err = -ENOMEM;
1191 return NULL;
1192 }
1193
1194 ptr->intel_pt_pmu = intel_pt_pmu;
1195 ptr->itr.pmu = intel_pt_pmu;
1196 ptr->itr.recording_options = intel_pt_recording_options;
1197 ptr->itr.info_priv_size = intel_pt_info_priv_size;
1198 ptr->itr.info_fill = intel_pt_info_fill;
1199 ptr->itr.free = intel_pt_recording_free;
1200 ptr->itr.snapshot_start = intel_pt_snapshot_start;
1201 ptr->itr.snapshot_finish = intel_pt_snapshot_finish;
1202 ptr->itr.find_snapshot = intel_pt_find_snapshot;
1203 ptr->itr.parse_snapshot_options = intel_pt_parse_snapshot_options;
1204 ptr->itr.reference = intel_pt_reference;
1205 ptr->itr.read_finish = auxtrace_record__read_finish;
1206 /*
1207 * Decoding starts at a PSB packet. Minimum PSB period is 2K so 4K
1208 * should give at least 1 PSB per sample.
1209 */
1210 ptr->itr.default_aux_sample_size = 4096;
1211 return &ptr->itr;
1212 }
1213