2 * intel-bts.c: Intel Processor Trace support
3 * Copyright (c) 2013-2015, Intel Corporation.
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
9 * This program is distributed in the hope 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
20 #include <linux/kernel.h>
21 #include <linux/types.h>
22 #include <linux/bitops.h>
23 #include <linux/log2.h>
33 #include "thread-stack.h"
37 #include "intel-pt-decoder/intel-pt-insn-decoder.h"
38 #include "intel-bts.h"
40 #define MAX_TIMESTAMP (~0ULL)
42 #define INTEL_BTS_ERR_NOINSN 5
43 #define INTEL_BTS_ERR_LOST 9
45 #if __BYTE_ORDER == __BIG_ENDIAN
46 #define le64_to_cpu bswap_64
52 struct auxtrace auxtrace;
53 struct auxtrace_queues queues;
54 struct auxtrace_heap heap;
56 struct perf_session *session;
57 struct machine *machine;
62 struct perf_tsc_conversion tc;
63 bool cap_user_time_zero;
64 struct itrace_synth_opts synth_opts;
67 u64 branches_sample_type;
69 size_t branches_event_size;
70 bool synth_needs_swap;
71 unsigned long num_events;
74 struct intel_bts_queue {
75 struct intel_bts *bts;
76 unsigned int queue_nr;
77 struct auxtrace_buffer *buffer;
84 struct intel_pt_insn intel_pt_insn;
94 static void intel_bts_dump(struct intel_bts *bts __maybe_unused,
95 unsigned char *buf, size_t len)
97 struct branch *branch;
98 size_t i, pos = 0, br_sz = sizeof(struct branch), sz;
99 const char *color = PERF_COLOR_BLUE;
101 color_fprintf(stdout, color,
102 ". ... Intel BTS data: size %zu bytes\n",
111 color_fprintf(stdout, color, " %08x: ", pos);
112 for (i = 0; i < sz; i++)
113 color_fprintf(stdout, color, " %02x", buf[i]);
114 for (; i < br_sz; i++)
115 color_fprintf(stdout, color, " ");
117 branch = (struct branch *)buf;
118 color_fprintf(stdout, color, " %"PRIx64" -> %"PRIx64" %s\n",
119 le64_to_cpu(branch->from),
120 le64_to_cpu(branch->to),
121 le64_to_cpu(branch->misc) & 0x10 ?
124 color_fprintf(stdout, color, " Bad record!\n");
132 static void intel_bts_dump_event(struct intel_bts *bts, unsigned char *buf,
136 intel_bts_dump(bts, buf, len);
139 static int intel_bts_lost(struct intel_bts *bts, struct perf_sample *sample)
141 union perf_event event;
144 auxtrace_synth_error(&event.auxtrace_error, PERF_AUXTRACE_ERROR_ITRACE,
145 INTEL_BTS_ERR_LOST, sample->cpu, sample->pid,
146 sample->tid, 0, "Lost trace data");
148 err = perf_session__deliver_synth_event(bts->session, &event, NULL);
150 pr_err("Intel BTS: failed to deliver error event, error %d\n",
156 static struct intel_bts_queue *intel_bts_alloc_queue(struct intel_bts *bts,
157 unsigned int queue_nr)
159 struct intel_bts_queue *btsq;
161 btsq = zalloc(sizeof(struct intel_bts_queue));
166 btsq->queue_nr = queue_nr;
174 static int intel_bts_setup_queue(struct intel_bts *bts,
175 struct auxtrace_queue *queue,
176 unsigned int queue_nr)
178 struct intel_bts_queue *btsq = queue->priv;
180 if (list_empty(&queue->head))
184 btsq = intel_bts_alloc_queue(bts, queue_nr);
189 if (queue->cpu != -1)
190 btsq->cpu = queue->cpu;
191 btsq->tid = queue->tid;
194 if (bts->sampling_mode)
197 if (!btsq->on_heap && !btsq->buffer) {
200 btsq->buffer = auxtrace_buffer__next(queue, NULL);
204 ret = auxtrace_heap__add(&bts->heap, queue_nr,
205 btsq->buffer->reference);
208 btsq->on_heap = true;
214 static int intel_bts_setup_queues(struct intel_bts *bts)
219 for (i = 0; i < bts->queues.nr_queues; i++) {
220 ret = intel_bts_setup_queue(bts, &bts->queues.queue_array[i],
228 static inline int intel_bts_update_queues(struct intel_bts *bts)
230 if (bts->queues.new_data) {
231 bts->queues.new_data = false;
232 return intel_bts_setup_queues(bts);
237 static unsigned char *intel_bts_find_overlap(unsigned char *buf_a, size_t len_a,
238 unsigned char *buf_b, size_t len_b)
243 offs = len_a - len_b;
247 for (; offs < len_a; offs += sizeof(struct branch)) {
249 if (!memcmp(buf_a + offs, buf_b, len))
256 static int intel_bts_do_fix_overlap(struct auxtrace_queue *queue,
257 struct auxtrace_buffer *b)
259 struct auxtrace_buffer *a;
262 if (b->list.prev == &queue->head)
264 a = list_entry(b->list.prev, struct auxtrace_buffer, list);
265 start = intel_bts_find_overlap(a->data, a->size, b->data, b->size);
268 b->use_size = b->data + b->size - start;
273 static int intel_bts_synth_branch_sample(struct intel_bts_queue *btsq,
274 struct branch *branch)
277 struct intel_bts *bts = btsq->bts;
278 union perf_event event;
279 struct perf_sample sample = { .ip = 0, };
281 if (bts->synth_opts.initial_skip &&
282 bts->num_events++ <= bts->synth_opts.initial_skip)
285 event.sample.header.type = PERF_RECORD_SAMPLE;
286 event.sample.header.misc = PERF_RECORD_MISC_USER;
287 event.sample.header.size = sizeof(struct perf_event_header);
289 sample.cpumode = PERF_RECORD_MISC_USER;
290 sample.ip = le64_to_cpu(branch->from);
291 sample.pid = btsq->pid;
292 sample.tid = btsq->tid;
293 sample.addr = le64_to_cpu(branch->to);
294 sample.id = btsq->bts->branches_id;
295 sample.stream_id = btsq->bts->branches_id;
297 sample.cpu = btsq->cpu;
298 sample.flags = btsq->sample_flags;
299 sample.insn_len = btsq->intel_pt_insn.length;
300 memcpy(sample.insn, btsq->intel_pt_insn.buf, INTEL_PT_INSN_BUF_SZ);
302 if (bts->synth_opts.inject) {
303 event.sample.header.size = bts->branches_event_size;
304 ret = perf_event__synthesize_sample(&event,
305 bts->branches_sample_type,
307 bts->synth_needs_swap);
312 ret = perf_session__deliver_synth_event(bts->session, &event, &sample);
314 pr_err("Intel BTS: failed to deliver branch event, error %d\n",
320 static int intel_bts_get_next_insn(struct intel_bts_queue *btsq, u64 ip)
322 struct machine *machine = btsq->bts->machine;
323 struct thread *thread;
324 struct addr_location al;
325 unsigned char buf[INTEL_PT_INSN_BUF_SZ];
331 if (machine__kernel_ip(machine, ip))
332 cpumode = PERF_RECORD_MISC_KERNEL;
334 cpumode = PERF_RECORD_MISC_USER;
336 thread = machine__find_thread(machine, -1, btsq->tid);
340 thread__find_addr_map(thread, cpumode, MAP__FUNCTION, ip, &al);
341 if (!al.map || !al.map->dso)
344 len = dso__data_read_addr(al.map->dso, al.map, machine, ip, buf,
345 INTEL_PT_INSN_BUF_SZ);
349 /* Load maps to ensure dso->is_64_bit has been updated */
352 x86_64 = al.map->dso->is_64_bit;
354 if (intel_pt_get_insn(buf, len, x86_64, &btsq->intel_pt_insn))
363 static int intel_bts_synth_error(struct intel_bts *bts, int cpu, pid_t pid,
366 union perf_event event;
369 auxtrace_synth_error(&event.auxtrace_error, PERF_AUXTRACE_ERROR_ITRACE,
370 INTEL_BTS_ERR_NOINSN, cpu, pid, tid, ip,
371 "Failed to get instruction");
373 err = perf_session__deliver_synth_event(bts->session, &event, NULL);
375 pr_err("Intel BTS: failed to deliver error event, error %d\n",
381 static int intel_bts_get_branch_type(struct intel_bts_queue *btsq,
382 struct branch *branch)
388 btsq->sample_flags = PERF_IP_FLAG_BRANCH |
389 PERF_IP_FLAG_TRACE_BEGIN;
391 btsq->sample_flags = 0;
392 btsq->intel_pt_insn.length = 0;
393 } else if (!branch->to) {
394 btsq->sample_flags = PERF_IP_FLAG_BRANCH |
395 PERF_IP_FLAG_TRACE_END;
396 btsq->intel_pt_insn.length = 0;
398 err = intel_bts_get_next_insn(btsq, branch->from);
400 btsq->sample_flags = 0;
401 btsq->intel_pt_insn.length = 0;
402 if (!btsq->bts->synth_opts.errors)
404 err = intel_bts_synth_error(btsq->bts, btsq->cpu,
405 btsq->pid, btsq->tid,
409 btsq->sample_flags = intel_pt_insn_type(btsq->intel_pt_insn.op);
410 /* Check for an async branch into the kernel */
411 if (!machine__kernel_ip(btsq->bts->machine, branch->from) &&
412 machine__kernel_ip(btsq->bts->machine, branch->to) &&
413 btsq->sample_flags != (PERF_IP_FLAG_BRANCH |
415 PERF_IP_FLAG_SYSCALLRET))
416 btsq->sample_flags = PERF_IP_FLAG_BRANCH |
419 PERF_IP_FLAG_INTERRUPT;
425 static int intel_bts_process_buffer(struct intel_bts_queue *btsq,
426 struct auxtrace_buffer *buffer,
427 struct thread *thread)
429 struct branch *branch;
430 size_t sz, bsz = sizeof(struct branch);
431 u32 filter = btsq->bts->branches_filter;
434 if (buffer->use_data) {
435 sz = buffer->use_size;
436 branch = buffer->use_data;
439 branch = buffer->data;
442 if (!btsq->bts->sample_branches)
445 for (; sz > bsz; branch += 1, sz -= bsz) {
446 if (!branch->from && !branch->to)
448 intel_bts_get_branch_type(btsq, branch);
449 if (btsq->bts->synth_opts.thread_stack)
450 thread_stack__event(thread, btsq->sample_flags,
451 le64_to_cpu(branch->from),
452 le64_to_cpu(branch->to),
453 btsq->intel_pt_insn.length,
454 buffer->buffer_nr + 1);
455 if (filter && !(filter & btsq->sample_flags))
457 err = intel_bts_synth_branch_sample(btsq, branch);
464 static int intel_bts_process_queue(struct intel_bts_queue *btsq, u64 *timestamp)
466 struct auxtrace_buffer *buffer = btsq->buffer, *old_buffer = buffer;
467 struct auxtrace_queue *queue;
468 struct thread *thread;
474 if (btsq->pid == -1) {
475 thread = machine__find_thread(btsq->bts->machine, -1,
478 btsq->pid = thread->pid_;
480 thread = machine__findnew_thread(btsq->bts->machine, btsq->pid,
484 queue = &btsq->bts->queues.queue_array[btsq->queue_nr];
487 buffer = auxtrace_buffer__next(queue, NULL);
490 if (!btsq->bts->sampling_mode)
496 /* Currently there is no support for split buffers */
497 if (buffer->consecutive) {
503 int fd = perf_data_file__fd(btsq->bts->session->file);
505 buffer->data = auxtrace_buffer__get_data(buffer, fd);
512 if (btsq->bts->snapshot_mode && !buffer->consecutive &&
513 intel_bts_do_fix_overlap(queue, buffer)) {
518 if (!btsq->bts->synth_opts.callchain &&
519 !btsq->bts->synth_opts.thread_stack && thread &&
520 (!old_buffer || btsq->bts->sampling_mode ||
521 (btsq->bts->snapshot_mode && !buffer->consecutive)))
522 thread_stack__set_trace_nr(thread, buffer->buffer_nr + 1);
524 err = intel_bts_process_buffer(btsq, buffer, thread);
526 auxtrace_buffer__drop_data(buffer);
528 btsq->buffer = auxtrace_buffer__next(queue, buffer);
531 *timestamp = btsq->buffer->reference;
533 if (!btsq->bts->sampling_mode)
541 static int intel_bts_flush_queue(struct intel_bts_queue *btsq)
547 ret = intel_bts_process_queue(btsq, &ts);
556 static int intel_bts_process_tid_exit(struct intel_bts *bts, pid_t tid)
558 struct auxtrace_queues *queues = &bts->queues;
561 for (i = 0; i < queues->nr_queues; i++) {
562 struct auxtrace_queue *queue = &bts->queues.queue_array[i];
563 struct intel_bts_queue *btsq = queue->priv;
565 if (btsq && btsq->tid == tid)
566 return intel_bts_flush_queue(btsq);
571 static int intel_bts_process_queues(struct intel_bts *bts, u64 timestamp)
574 unsigned int queue_nr;
575 struct auxtrace_queue *queue;
576 struct intel_bts_queue *btsq;
580 if (!bts->heap.heap_cnt)
583 if (bts->heap.heap_array[0].ordinal > timestamp)
586 queue_nr = bts->heap.heap_array[0].queue_nr;
587 queue = &bts->queues.queue_array[queue_nr];
590 auxtrace_heap__pop(&bts->heap);
592 ret = intel_bts_process_queue(btsq, &ts);
594 auxtrace_heap__add(&bts->heap, queue_nr, ts);
599 ret = auxtrace_heap__add(&bts->heap, queue_nr, ts);
603 btsq->on_heap = false;
610 static int intel_bts_process_event(struct perf_session *session,
611 union perf_event *event,
612 struct perf_sample *sample,
613 struct perf_tool *tool)
615 struct intel_bts *bts = container_of(session->auxtrace, struct intel_bts,
623 if (!tool->ordered_events) {
624 pr_err("Intel BTS requires ordered events\n");
628 if (sample->time && sample->time != (u64)-1)
629 timestamp = perf_time_to_tsc(sample->time, &bts->tc);
633 err = intel_bts_update_queues(bts);
637 err = intel_bts_process_queues(bts, timestamp);
640 if (event->header.type == PERF_RECORD_EXIT) {
641 err = intel_bts_process_tid_exit(bts, event->fork.tid);
646 if (event->header.type == PERF_RECORD_AUX &&
647 (event->aux.flags & PERF_AUX_FLAG_TRUNCATED) &&
648 bts->synth_opts.errors)
649 err = intel_bts_lost(bts, sample);
654 static int intel_bts_process_auxtrace_event(struct perf_session *session,
655 union perf_event *event,
656 struct perf_tool *tool __maybe_unused)
658 struct intel_bts *bts = container_of(session->auxtrace, struct intel_bts,
661 if (bts->sampling_mode)
664 if (!bts->data_queued) {
665 struct auxtrace_buffer *buffer;
667 int fd = perf_data_file__fd(session->file);
670 if (perf_data_file__is_pipe(session->file)) {
673 data_offset = lseek(fd, 0, SEEK_CUR);
674 if (data_offset == -1)
678 err = auxtrace_queues__add_event(&bts->queues, session, event,
679 data_offset, &buffer);
683 /* Dump here now we have copied a piped trace out of the pipe */
685 if (auxtrace_buffer__get_data(buffer, fd)) {
686 intel_bts_dump_event(bts, buffer->data,
688 auxtrace_buffer__put_data(buffer);
696 static int intel_bts_flush(struct perf_session *session,
697 struct perf_tool *tool __maybe_unused)
699 struct intel_bts *bts = container_of(session->auxtrace, struct intel_bts,
703 if (dump_trace || bts->sampling_mode)
706 if (!tool->ordered_events)
709 ret = intel_bts_update_queues(bts);
713 return intel_bts_process_queues(bts, MAX_TIMESTAMP);
716 static void intel_bts_free_queue(void *priv)
718 struct intel_bts_queue *btsq = priv;
725 static void intel_bts_free_events(struct perf_session *session)
727 struct intel_bts *bts = container_of(session->auxtrace, struct intel_bts,
729 struct auxtrace_queues *queues = &bts->queues;
732 for (i = 0; i < queues->nr_queues; i++) {
733 intel_bts_free_queue(queues->queue_array[i].priv);
734 queues->queue_array[i].priv = NULL;
736 auxtrace_queues__free(queues);
739 static void intel_bts_free(struct perf_session *session)
741 struct intel_bts *bts = container_of(session->auxtrace, struct intel_bts,
744 auxtrace_heap__free(&bts->heap);
745 intel_bts_free_events(session);
746 session->auxtrace = NULL;
750 struct intel_bts_synth {
751 struct perf_tool dummy_tool;
752 struct perf_session *session;
755 static int intel_bts_event_synth(struct perf_tool *tool,
756 union perf_event *event,
757 struct perf_sample *sample __maybe_unused,
758 struct machine *machine __maybe_unused)
760 struct intel_bts_synth *intel_bts_synth =
761 container_of(tool, struct intel_bts_synth, dummy_tool);
763 return perf_session__deliver_synth_event(intel_bts_synth->session,
767 static int intel_bts_synth_event(struct perf_session *session,
768 struct perf_event_attr *attr, u64 id)
770 struct intel_bts_synth intel_bts_synth;
772 memset(&intel_bts_synth, 0, sizeof(struct intel_bts_synth));
773 intel_bts_synth.session = session;
775 return perf_event__synthesize_attr(&intel_bts_synth.dummy_tool, attr, 1,
776 &id, intel_bts_event_synth);
779 static int intel_bts_synth_events(struct intel_bts *bts,
780 struct perf_session *session)
782 struct perf_evlist *evlist = session->evlist;
783 struct perf_evsel *evsel;
784 struct perf_event_attr attr;
789 evlist__for_each_entry(evlist, evsel) {
790 if (evsel->attr.type == bts->pmu_type && evsel->ids) {
797 pr_debug("There are no selected events with Intel BTS data\n");
801 memset(&attr, 0, sizeof(struct perf_event_attr));
802 attr.size = sizeof(struct perf_event_attr);
803 attr.type = PERF_TYPE_HARDWARE;
804 attr.sample_type = evsel->attr.sample_type & PERF_SAMPLE_MASK;
805 attr.sample_type |= PERF_SAMPLE_IP | PERF_SAMPLE_TID |
807 attr.sample_type &= ~(u64)PERF_SAMPLE_TIME;
808 attr.sample_type &= ~(u64)PERF_SAMPLE_CPU;
809 attr.exclude_user = evsel->attr.exclude_user;
810 attr.exclude_kernel = evsel->attr.exclude_kernel;
811 attr.exclude_hv = evsel->attr.exclude_hv;
812 attr.exclude_host = evsel->attr.exclude_host;
813 attr.exclude_guest = evsel->attr.exclude_guest;
814 attr.sample_id_all = evsel->attr.sample_id_all;
815 attr.read_format = evsel->attr.read_format;
817 id = evsel->id[0] + 1000000000;
821 if (bts->synth_opts.branches) {
822 attr.config = PERF_COUNT_HW_BRANCH_INSTRUCTIONS;
823 attr.sample_period = 1;
824 attr.sample_type |= PERF_SAMPLE_ADDR;
825 pr_debug("Synthesizing 'branches' event with id %" PRIu64 " sample type %#" PRIx64 "\n",
826 id, (u64)attr.sample_type);
827 err = intel_bts_synth_event(session, &attr, id);
829 pr_err("%s: failed to synthesize 'branches' event type\n",
833 bts->sample_branches = true;
834 bts->branches_sample_type = attr.sample_type;
835 bts->branches_id = id;
837 * We only use sample types from PERF_SAMPLE_MASK so we can use
838 * __perf_evsel__sample_size() here.
840 bts->branches_event_size = sizeof(struct sample_event) +
841 __perf_evsel__sample_size(attr.sample_type);
844 bts->synth_needs_swap = evsel->needs_swap;
849 static const char * const intel_bts_info_fmts[] = {
850 [INTEL_BTS_PMU_TYPE] = " PMU Type %"PRId64"\n",
851 [INTEL_BTS_TIME_SHIFT] = " Time Shift %"PRIu64"\n",
852 [INTEL_BTS_TIME_MULT] = " Time Muliplier %"PRIu64"\n",
853 [INTEL_BTS_TIME_ZERO] = " Time Zero %"PRIu64"\n",
854 [INTEL_BTS_CAP_USER_TIME_ZERO] = " Cap Time Zero %"PRId64"\n",
855 [INTEL_BTS_SNAPSHOT_MODE] = " Snapshot mode %"PRId64"\n",
858 static void intel_bts_print_info(u64 *arr, int start, int finish)
865 for (i = start; i <= finish; i++)
866 fprintf(stdout, intel_bts_info_fmts[i], arr[i]);
869 int intel_bts_process_auxtrace_info(union perf_event *event,
870 struct perf_session *session)
872 struct auxtrace_info_event *auxtrace_info = &event->auxtrace_info;
873 size_t min_sz = sizeof(u64) * INTEL_BTS_SNAPSHOT_MODE;
874 struct intel_bts *bts;
877 if (auxtrace_info->header.size < sizeof(struct auxtrace_info_event) +
881 bts = zalloc(sizeof(struct intel_bts));
885 err = auxtrace_queues__init(&bts->queues);
889 bts->session = session;
890 bts->machine = &session->machines.host; /* No kvm support */
891 bts->auxtrace_type = auxtrace_info->type;
892 bts->pmu_type = auxtrace_info->priv[INTEL_BTS_PMU_TYPE];
893 bts->tc.time_shift = auxtrace_info->priv[INTEL_BTS_TIME_SHIFT];
894 bts->tc.time_mult = auxtrace_info->priv[INTEL_BTS_TIME_MULT];
895 bts->tc.time_zero = auxtrace_info->priv[INTEL_BTS_TIME_ZERO];
896 bts->cap_user_time_zero =
897 auxtrace_info->priv[INTEL_BTS_CAP_USER_TIME_ZERO];
898 bts->snapshot_mode = auxtrace_info->priv[INTEL_BTS_SNAPSHOT_MODE];
900 bts->sampling_mode = false;
902 bts->auxtrace.process_event = intel_bts_process_event;
903 bts->auxtrace.process_auxtrace_event = intel_bts_process_auxtrace_event;
904 bts->auxtrace.flush_events = intel_bts_flush;
905 bts->auxtrace.free_events = intel_bts_free_events;
906 bts->auxtrace.free = intel_bts_free;
907 session->auxtrace = &bts->auxtrace;
909 intel_bts_print_info(&auxtrace_info->priv[0], INTEL_BTS_PMU_TYPE,
910 INTEL_BTS_SNAPSHOT_MODE);
915 if (session->itrace_synth_opts && session->itrace_synth_opts->set) {
916 bts->synth_opts = *session->itrace_synth_opts;
918 itrace_synth_opts__set_default(&bts->synth_opts);
919 if (session->itrace_synth_opts)
920 bts->synth_opts.thread_stack =
921 session->itrace_synth_opts->thread_stack;
924 if (bts->synth_opts.calls)
925 bts->branches_filter |= PERF_IP_FLAG_CALL | PERF_IP_FLAG_ASYNC |
926 PERF_IP_FLAG_TRACE_END;
927 if (bts->synth_opts.returns)
928 bts->branches_filter |= PERF_IP_FLAG_RETURN |
929 PERF_IP_FLAG_TRACE_BEGIN;
931 err = intel_bts_synth_events(bts, session);
933 goto err_free_queues;
935 err = auxtrace_queues__process_index(&bts->queues, session);
937 goto err_free_queues;
939 if (bts->queues.populated)
940 bts->data_queued = true;
945 auxtrace_queues__free(&bts->queues);
946 session->auxtrace = NULL;