/* * intel-bts.c: Intel Processor Trace support * Copyright (c) 2013-2015, Intel Corporation. * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, * version 2, as published by the Free Software Foundation. * * This program is distributed in the hope it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * */ #include #include #include #include #include #include #include "cpumap.h" #include "color.h" #include "evsel.h" #include "evlist.h" #include "machine.h" #include "session.h" #include "util.h" #include "thread.h" #include "thread-stack.h" #include "debug.h" #include "tsc.h" #include "auxtrace.h" #include "intel-pt-decoder/intel-pt-insn-decoder.h" #include "intel-bts.h" #define MAX_TIMESTAMP (~0ULL) #define INTEL_BTS_ERR_NOINSN 5 #define INTEL_BTS_ERR_LOST 9 #if __BYTE_ORDER == __BIG_ENDIAN #define le64_to_cpu bswap_64 #else #define le64_to_cpu #endif struct intel_bts { struct auxtrace auxtrace; struct auxtrace_queues queues; struct auxtrace_heap heap; u32 auxtrace_type; struct perf_session *session; struct machine *machine; bool sampling_mode; bool snapshot_mode; bool data_queued; u32 pmu_type; struct perf_tsc_conversion tc; bool cap_user_time_zero; struct itrace_synth_opts synth_opts; bool sample_branches; u32 branches_filter; u64 branches_sample_type; u64 branches_id; size_t branches_event_size; bool synth_needs_swap; }; struct intel_bts_queue { struct intel_bts *bts; unsigned int queue_nr; struct auxtrace_buffer *buffer; bool on_heap; bool done; pid_t pid; pid_t tid; int cpu; u64 time; struct intel_pt_insn intel_pt_insn; u32 sample_flags; }; struct branch { u64 from; u64 to; u64 misc; }; static void intel_bts_dump(struct intel_bts *bts __maybe_unused, unsigned char *buf, size_t len) { struct branch *branch; size_t i, pos = 0, br_sz = sizeof(struct branch), sz; const char *color = PERF_COLOR_BLUE; color_fprintf(stdout, color, ". ... Intel BTS data: size %zu bytes\n", len); while (len) { if (len >= br_sz) sz = br_sz; else sz = len; printf("."); color_fprintf(stdout, color, " %08x: ", pos); for (i = 0; i < sz; i++) color_fprintf(stdout, color, " %02x", buf[i]); for (; i < br_sz; i++) color_fprintf(stdout, color, " "); if (len >= br_sz) { branch = (struct branch *)buf; color_fprintf(stdout, color, " %"PRIx64" -> %"PRIx64" %s\n", le64_to_cpu(branch->from), le64_to_cpu(branch->to), le64_to_cpu(branch->misc) & 0x10 ? "pred" : "miss"); } else { color_fprintf(stdout, color, " Bad record!\n"); } pos += sz; buf += sz; len -= sz; } } static void intel_bts_dump_event(struct intel_bts *bts, unsigned char *buf, size_t len) { printf(".\n"); intel_bts_dump(bts, buf, len); } static int intel_bts_lost(struct intel_bts *bts, struct perf_sample *sample) { union perf_event event; int err; auxtrace_synth_error(&event.auxtrace_error, PERF_AUXTRACE_ERROR_ITRACE, INTEL_BTS_ERR_LOST, sample->cpu, sample->pid, sample->tid, 0, "Lost trace data"); err = perf_session__deliver_synth_event(bts->session, &event, NULL); if (err) pr_err("Intel BTS: failed to deliver error event, error %d\n", err); return err; } static struct intel_bts_queue *intel_bts_alloc_queue(struct intel_bts *bts, unsigned int queue_nr) { struct intel_bts_queue *btsq; btsq = zalloc(sizeof(struct intel_bts_queue)); if (!btsq) return NULL; btsq->bts = bts; btsq->queue_nr = queue_nr; btsq->pid = -1; btsq->tid = -1; btsq->cpu = -1; return btsq; } static int intel_bts_setup_queue(struct intel_bts *bts, struct auxtrace_queue *queue, unsigned int queue_nr) { struct intel_bts_queue *btsq = queue->priv; if (list_empty(&queue->head)) return 0; if (!btsq) { btsq = intel_bts_alloc_queue(bts, queue_nr); if (!btsq) return -ENOMEM; queue->priv = btsq; if (queue->cpu != -1) btsq->cpu = queue->cpu; btsq->tid = queue->tid; } if (bts->sampling_mode) return 0; if (!btsq->on_heap && !btsq->buffer) { int ret; btsq->buffer = auxtrace_buffer__next(queue, NULL); if (!btsq->buffer) return 0; ret = auxtrace_heap__add(&bts->heap, queue_nr, btsq->buffer->reference); if (ret) return ret; btsq->on_heap = true; } return 0; } static int intel_bts_setup_queues(struct intel_bts *bts) { unsigned int i; int ret; for (i = 0; i < bts->queues.nr_queues; i++) { ret = intel_bts_setup_queue(bts, &bts->queues.queue_array[i], i); if (ret) return ret; } return 0; } static inline int intel_bts_update_queues(struct intel_bts *bts) { if (bts->queues.new_data) { bts->queues.new_data = false; return intel_bts_setup_queues(bts); } return 0; } static unsigned char *intel_bts_find_overlap(unsigned char *buf_a, size_t len_a, unsigned char *buf_b, size_t len_b) { size_t offs, len; if (len_a > len_b) offs = len_a - len_b; else offs = 0; for (; offs < len_a; offs += sizeof(struct branch)) { len = len_a - offs; if (!memcmp(buf_a + offs, buf_b, len)) return buf_b + len; } return buf_b; } static int intel_bts_do_fix_overlap(struct auxtrace_queue *queue, struct auxtrace_buffer *b) { struct auxtrace_buffer *a; void *start; if (b->list.prev == &queue->head) return 0; a = list_entry(b->list.prev, struct auxtrace_buffer, list); start = intel_bts_find_overlap(a->data, a->size, b->data, b->size); if (!start) return -EINVAL; b->use_size = b->data + b->size - start; b->use_data = start; return 0; } static int intel_bts_synth_branch_sample(struct intel_bts_queue *btsq, struct branch *branch) { int ret; struct intel_bts *bts = btsq->bts; union perf_event event; struct perf_sample sample = { .ip = 0, }; event.sample.header.type = PERF_RECORD_SAMPLE; event.sample.header.misc = PERF_RECORD_MISC_USER; event.sample.header.size = sizeof(struct perf_event_header); sample.ip = le64_to_cpu(branch->from); sample.pid = btsq->pid; sample.tid = btsq->tid; sample.addr = le64_to_cpu(branch->to); sample.id = btsq->bts->branches_id; sample.stream_id = btsq->bts->branches_id; sample.period = 1; sample.cpu = btsq->cpu; sample.flags = btsq->sample_flags; sample.insn_len = btsq->intel_pt_insn.length; if (bts->synth_opts.inject) { event.sample.header.size = bts->branches_event_size; ret = perf_event__synthesize_sample(&event, bts->branches_sample_type, 0, &sample, bts->synth_needs_swap); if (ret) return ret; } ret = perf_session__deliver_synth_event(bts->session, &event, &sample); if (ret) pr_err("Intel BTS: failed to deliver branch event, error %d\n", ret); return ret; } static int intel_bts_get_next_insn(struct intel_bts_queue *btsq, u64 ip) { struct machine *machine = btsq->bts->machine; struct thread *thread; struct addr_location al; unsigned char buf[1024]; size_t bufsz; ssize_t len; int x86_64; uint8_t cpumode; int err = -1; bufsz = intel_pt_insn_max_size(); if (machine__kernel_ip(machine, ip)) cpumode = PERF_RECORD_MISC_KERNEL; else cpumode = PERF_RECORD_MISC_USER; thread = machine__find_thread(machine, -1, btsq->tid); if (!thread) return -1; thread__find_addr_map(thread, cpumode, MAP__FUNCTION, ip, &al); if (!al.map || !al.map->dso) goto out_put; len = dso__data_read_addr(al.map->dso, al.map, machine, ip, buf, bufsz); if (len <= 0) goto out_put; /* Load maps to ensure dso->is_64_bit has been updated */ map__load(al.map, machine->symbol_filter); x86_64 = al.map->dso->is_64_bit; if (intel_pt_get_insn(buf, len, x86_64, &btsq->intel_pt_insn)) goto out_put; err = 0; out_put: thread__put(thread); return err; } static int intel_bts_synth_error(struct intel_bts *bts, int cpu, pid_t pid, pid_t tid, u64 ip) { union perf_event event; int err; auxtrace_synth_error(&event.auxtrace_error, PERF_AUXTRACE_ERROR_ITRACE, INTEL_BTS_ERR_NOINSN, cpu, pid, tid, ip, "Failed to get instruction"); err = perf_session__deliver_synth_event(bts->session, &event, NULL); if (err) pr_err("Intel BTS: failed to deliver error event, error %d\n", err); return err; } static int intel_bts_get_branch_type(struct intel_bts_queue *btsq, struct branch *branch) { int err; if (!branch->from) { if (branch->to) btsq->sample_flags = PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_TRACE_BEGIN; else btsq->sample_flags = 0; btsq->intel_pt_insn.length = 0; } else if (!branch->to) { btsq->sample_flags = PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_TRACE_END; btsq->intel_pt_insn.length = 0; } else { err = intel_bts_get_next_insn(btsq, branch->from); if (err) { btsq->sample_flags = 0; btsq->intel_pt_insn.length = 0; if (!btsq->bts->synth_opts.errors) return 0; err = intel_bts_synth_error(btsq->bts, btsq->cpu, btsq->pid, btsq->tid, branch->from); return err; } btsq->sample_flags = intel_pt_insn_type(btsq->intel_pt_insn.op); /* Check for an async branch into the kernel */ if (!machine__kernel_ip(btsq->bts->machine, branch->from) && machine__kernel_ip(btsq->bts->machine, branch->to) && btsq->sample_flags != (PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CALL | PERF_IP_FLAG_SYSCALLRET)) btsq->sample_flags = PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CALL | PERF_IP_FLAG_ASYNC | PERF_IP_FLAG_INTERRUPT; } return 0; } static int intel_bts_process_buffer(struct intel_bts_queue *btsq, struct auxtrace_buffer *buffer) { struct branch *branch; size_t sz, bsz = sizeof(struct branch); u32 filter = btsq->bts->branches_filter; int err = 0; if (buffer->use_data) { sz = buffer->use_size; branch = buffer->use_data; } else { sz = buffer->size; branch = buffer->data; } if (!btsq->bts->sample_branches) return 0; for (; sz > bsz; branch += 1, sz -= bsz) { if (!branch->from && !branch->to) continue; intel_bts_get_branch_type(btsq, branch); if (filter && !(filter & btsq->sample_flags)) continue; err = intel_bts_synth_branch_sample(btsq, branch); if (err) break; } return err; } static int intel_bts_process_queue(struct intel_bts_queue *btsq, u64 *timestamp) { struct auxtrace_buffer *buffer = btsq->buffer, *old_buffer = buffer; struct auxtrace_queue *queue; struct thread *thread; int err; if (btsq->done) return 1; if (btsq->pid == -1) { thread = machine__find_thread(btsq->bts->machine, -1, btsq->tid); if (thread) btsq->pid = thread->pid_; } else { thread = machine__findnew_thread(btsq->bts->machine, btsq->pid, btsq->tid); } queue = &btsq->bts->queues.queue_array[btsq->queue_nr]; if (!buffer) buffer = auxtrace_buffer__next(queue, NULL); if (!buffer) { if (!btsq->bts->sampling_mode) btsq->done = 1; err = 1; goto out_put; } /* Currently there is no support for split buffers */ if (buffer->consecutive) { err = -EINVAL; goto out_put; } if (!buffer->data) { int fd = perf_data_file__fd(btsq->bts->session->file); buffer->data = auxtrace_buffer__get_data(buffer, fd); if (!buffer->data) { err = -ENOMEM; goto out_put; } } if (btsq->bts->snapshot_mode && !buffer->consecutive && intel_bts_do_fix_overlap(queue, buffer)) { err = -ENOMEM; goto out_put; } if (!btsq->bts->synth_opts.callchain && thread && (!old_buffer || btsq->bts->sampling_mode || (btsq->bts->snapshot_mode && !buffer->consecutive))) thread_stack__set_trace_nr(thread, buffer->buffer_nr + 1); err = intel_bts_process_buffer(btsq, buffer); auxtrace_buffer__drop_data(buffer); btsq->buffer = auxtrace_buffer__next(queue, buffer); if (btsq->buffer) { if (timestamp) *timestamp = btsq->buffer->reference; } else { if (!btsq->bts->sampling_mode) btsq->done = 1; } out_put: thread__put(thread); return err; } static int intel_bts_flush_queue(struct intel_bts_queue *btsq) { u64 ts = 0; int ret; while (1) { ret = intel_bts_process_queue(btsq, &ts); if (ret < 0) return ret; if (ret) break; } return 0; } static int intel_bts_process_tid_exit(struct intel_bts *bts, pid_t tid) { struct auxtrace_queues *queues = &bts->queues; unsigned int i; for (i = 0; i < queues->nr_queues; i++) { struct auxtrace_queue *queue = &bts->queues.queue_array[i]; struct intel_bts_queue *btsq = queue->priv; if (btsq && btsq->tid == tid) return intel_bts_flush_queue(btsq); } return 0; } static int intel_bts_process_queues(struct intel_bts *bts, u64 timestamp) { while (1) { unsigned int queue_nr; struct auxtrace_queue *queue; struct intel_bts_queue *btsq; u64 ts = 0; int ret; if (!bts->heap.heap_cnt) return 0; if (bts->heap.heap_array[0].ordinal > timestamp) return 0; queue_nr = bts->heap.heap_array[0].queue_nr; queue = &bts->queues.queue_array[queue_nr]; btsq = queue->priv; auxtrace_heap__pop(&bts->heap); ret = intel_bts_process_queue(btsq, &ts); if (ret < 0) { auxtrace_heap__add(&bts->heap, queue_nr, ts); return ret; } if (!ret) { ret = auxtrace_heap__add(&bts->heap, queue_nr, ts); if (ret < 0) return ret; } else { btsq->on_heap = false; } } return 0; } static int intel_bts_process_event(struct perf_session *session, union perf_event *event, struct perf_sample *sample, struct perf_tool *tool) { struct intel_bts *bts = container_of(session->auxtrace, struct intel_bts, auxtrace); u64 timestamp; int err; if (dump_trace) return 0; if (!tool->ordered_events) { pr_err("Intel BTS requires ordered events\n"); return -EINVAL; } if (sample->time && sample->time != (u64)-1) timestamp = perf_time_to_tsc(sample->time, &bts->tc); else timestamp = 0; err = intel_bts_update_queues(bts); if (err) return err; err = intel_bts_process_queues(bts, timestamp); if (err) return err; if (event->header.type == PERF_RECORD_EXIT) { err = intel_bts_process_tid_exit(bts, event->fork.tid); if (err) return err; } if (event->header.type == PERF_RECORD_AUX && (event->aux.flags & PERF_AUX_FLAG_TRUNCATED) && bts->synth_opts.errors) err = intel_bts_lost(bts, sample); return err; } static int intel_bts_process_auxtrace_event(struct perf_session *session, union perf_event *event, struct perf_tool *tool __maybe_unused) { struct intel_bts *bts = container_of(session->auxtrace, struct intel_bts, auxtrace); if (bts->sampling_mode) return 0; if (!bts->data_queued) { struct auxtrace_buffer *buffer; off_t data_offset; int fd = perf_data_file__fd(session->file); int err; if (perf_data_file__is_pipe(session->file)) { data_offset = 0; } else { data_offset = lseek(fd, 0, SEEK_CUR); if (data_offset == -1) return -errno; } err = auxtrace_queues__add_event(&bts->queues, session, event, data_offset, &buffer); if (err) return err; /* Dump here now we have copied a piped trace out of the pipe */ if (dump_trace) { if (auxtrace_buffer__get_data(buffer, fd)) { intel_bts_dump_event(bts, buffer->data, buffer->size); auxtrace_buffer__put_data(buffer); } } } return 0; } static int intel_bts_flush(struct perf_session *session __maybe_unused, struct perf_tool *tool __maybe_unused) { struct intel_bts *bts = container_of(session->auxtrace, struct intel_bts, auxtrace); int ret; if (dump_trace || bts->sampling_mode) return 0; if (!tool->ordered_events) return -EINVAL; ret = intel_bts_update_queues(bts); if (ret < 0) return ret; return intel_bts_process_queues(bts, MAX_TIMESTAMP); } static void intel_bts_free_queue(void *priv) { struct intel_bts_queue *btsq = priv; if (!btsq) return; free(btsq); } static void intel_bts_free_events(struct perf_session *session) { struct intel_bts *bts = container_of(session->auxtrace, struct intel_bts, auxtrace); struct auxtrace_queues *queues = &bts->queues; unsigned int i; for (i = 0; i < queues->nr_queues; i++) { intel_bts_free_queue(queues->queue_array[i].priv); queues->queue_array[i].priv = NULL; } auxtrace_queues__free(queues); } static void intel_bts_free(struct perf_session *session) { struct intel_bts *bts = container_of(session->auxtrace, struct intel_bts, auxtrace); auxtrace_heap__free(&bts->heap); intel_bts_free_events(session); session->auxtrace = NULL; free(bts); } struct intel_bts_synth { struct perf_tool dummy_tool; struct perf_session *session; }; static int intel_bts_event_synth(struct perf_tool *tool, union perf_event *event, struct perf_sample *sample __maybe_unused, struct machine *machine __maybe_unused) { struct intel_bts_synth *intel_bts_synth = container_of(tool, struct intel_bts_synth, dummy_tool); return perf_session__deliver_synth_event(intel_bts_synth->session, event, NULL); } static int intel_bts_synth_event(struct perf_session *session, struct perf_event_attr *attr, u64 id) { struct intel_bts_synth intel_bts_synth; memset(&intel_bts_synth, 0, sizeof(struct intel_bts_synth)); intel_bts_synth.session = session; return perf_event__synthesize_attr(&intel_bts_synth.dummy_tool, attr, 1, &id, intel_bts_event_synth); } static int intel_bts_synth_events(struct intel_bts *bts, struct perf_session *session) { struct perf_evlist *evlist = session->evlist; struct perf_evsel *evsel; struct perf_event_attr attr; bool found = false; u64 id; int err; evlist__for_each(evlist, evsel) { if (evsel->attr.type == bts->pmu_type && evsel->ids) { found = true; break; } } if (!found) { pr_debug("There are no selected events with Intel BTS data\n"); return 0; } memset(&attr, 0, sizeof(struct perf_event_attr)); attr.size = sizeof(struct perf_event_attr); attr.type = PERF_TYPE_HARDWARE; attr.sample_type = evsel->attr.sample_type & PERF_SAMPLE_MASK; attr.sample_type |= PERF_SAMPLE_IP | PERF_SAMPLE_TID | PERF_SAMPLE_PERIOD; attr.sample_type &= ~(u64)PERF_SAMPLE_TIME; attr.sample_type &= ~(u64)PERF_SAMPLE_CPU; attr.exclude_user = evsel->attr.exclude_user; attr.exclude_kernel = evsel->attr.exclude_kernel; attr.exclude_hv = evsel->attr.exclude_hv; attr.exclude_host = evsel->attr.exclude_host; attr.exclude_guest = evsel->attr.exclude_guest; attr.sample_id_all = evsel->attr.sample_id_all; attr.read_format = evsel->attr.read_format; id = evsel->id[0] + 1000000000; if (!id) id = 1; if (bts->synth_opts.branches) { attr.config = PERF_COUNT_HW_BRANCH_INSTRUCTIONS; attr.sample_period = 1; attr.sample_type |= PERF_SAMPLE_ADDR; pr_debug("Synthesizing 'branches' event with id %" PRIu64 " sample type %#" PRIx64 "\n", id, (u64)attr.sample_type); err = intel_bts_synth_event(session, &attr, id); if (err) { pr_err("%s: failed to synthesize 'branches' event type\n", __func__); return err; } bts->sample_branches = true; bts->branches_sample_type = attr.sample_type; bts->branches_id = id; /* * We only use sample types from PERF_SAMPLE_MASK so we can use * __perf_evsel__sample_size() here. */ bts->branches_event_size = sizeof(struct sample_event) + __perf_evsel__sample_size(attr.sample_type); } bts->synth_needs_swap = evsel->needs_swap; return 0; } static const char * const intel_bts_info_fmts[] = { [INTEL_BTS_PMU_TYPE] = " PMU Type %"PRId64"\n", [INTEL_BTS_TIME_SHIFT] = " Time Shift %"PRIu64"\n", [INTEL_BTS_TIME_MULT] = " Time Muliplier %"PRIu64"\n", [INTEL_BTS_TIME_ZERO] = " Time Zero %"PRIu64"\n", [INTEL_BTS_CAP_USER_TIME_ZERO] = " Cap Time Zero %"PRId64"\n", [INTEL_BTS_SNAPSHOT_MODE] = " Snapshot mode %"PRId64"\n", }; static void intel_bts_print_info(u64 *arr, int start, int finish) { int i; if (!dump_trace) return; for (i = start; i <= finish; i++) fprintf(stdout, intel_bts_info_fmts[i], arr[i]); } u64 intel_bts_auxtrace_info_priv[INTEL_BTS_AUXTRACE_PRIV_SIZE]; int intel_bts_process_auxtrace_info(union perf_event *event, struct perf_session *session) { struct auxtrace_info_event *auxtrace_info = &event->auxtrace_info; size_t min_sz = sizeof(u64) * INTEL_BTS_SNAPSHOT_MODE; struct intel_bts *bts; int err; if (auxtrace_info->header.size < sizeof(struct auxtrace_info_event) + min_sz) return -EINVAL; bts = zalloc(sizeof(struct intel_bts)); if (!bts) return -ENOMEM; err = auxtrace_queues__init(&bts->queues); if (err) goto err_free; bts->session = session; bts->machine = &session->machines.host; /* No kvm support */ bts->auxtrace_type = auxtrace_info->type; bts->pmu_type = auxtrace_info->priv[INTEL_BTS_PMU_TYPE]; bts->tc.time_shift = auxtrace_info->priv[INTEL_BTS_TIME_SHIFT]; bts->tc.time_mult = auxtrace_info->priv[INTEL_BTS_TIME_MULT]; bts->tc.time_zero = auxtrace_info->priv[INTEL_BTS_TIME_ZERO]; bts->cap_user_time_zero = auxtrace_info->priv[INTEL_BTS_CAP_USER_TIME_ZERO]; bts->snapshot_mode = auxtrace_info->priv[INTEL_BTS_SNAPSHOT_MODE]; bts->sampling_mode = false; bts->auxtrace.process_event = intel_bts_process_event; bts->auxtrace.process_auxtrace_event = intel_bts_process_auxtrace_event; bts->auxtrace.flush_events = intel_bts_flush; bts->auxtrace.free_events = intel_bts_free_events; bts->auxtrace.free = intel_bts_free; session->auxtrace = &bts->auxtrace; intel_bts_print_info(&auxtrace_info->priv[0], INTEL_BTS_PMU_TYPE, INTEL_BTS_SNAPSHOT_MODE); if (dump_trace) return 0; if (session->itrace_synth_opts && session->itrace_synth_opts->set) bts->synth_opts = *session->itrace_synth_opts; else itrace_synth_opts__set_default(&bts->synth_opts); if (bts->synth_opts.calls) bts->branches_filter |= PERF_IP_FLAG_CALL | PERF_IP_FLAG_ASYNC | PERF_IP_FLAG_TRACE_END; if (bts->synth_opts.returns) bts->branches_filter |= PERF_IP_FLAG_RETURN | PERF_IP_FLAG_TRACE_BEGIN; err = intel_bts_synth_events(bts, session); if (err) goto err_free_queues; err = auxtrace_queues__process_index(&bts->queues, session); if (err) goto err_free_queues; if (bts->queues.populated) bts->data_queued = true; return 0; err_free_queues: auxtrace_queues__free(&bts->queues); session->auxtrace = NULL; err_free: free(bts); return err; }