diff --git a/tools/perf/Documentation/perf-inject.txt b/tools/perf/Documentation/perf-inject.txt index c972032f4ca0..95dfdf39666e 100644 --- a/tools/perf/Documentation/perf-inject.txt +++ b/tools/perf/Documentation/perf-inject.txt @@ -109,6 +109,11 @@ include::itrace.txt[] should be used, and also --buildid-all and --switch-events may be useful. +--convert-callchain:: + Parse DWARF callchains and convert them to usual callchains. This also + discards stack and register data from the samples. This will lose + inlined callchain entries. + :GMEXAMPLECMD: inject :GMEXAMPLESUBCMD: include::guestmount.txt[] diff --git a/tools/perf/builtin-inject.c b/tools/perf/builtin-inject.c index 6080afec537d..e2a653280e1b 100644 --- a/tools/perf/builtin-inject.c +++ b/tools/perf/builtin-inject.c @@ -122,6 +122,7 @@ struct perf_inject { bool in_place_update; bool in_place_update_dry_run; bool copy_kcore_dir; + bool convert_callchain; const char *input_name; struct perf_data output; u64 bytes_written; @@ -133,6 +134,7 @@ struct perf_inject { struct guest_session guest_session; struct strlist *known_build_ids; const struct evsel *mmap_evsel; + struct ip_callchain *raw_callchain; }; struct event_entry { @@ -383,6 +385,90 @@ static int perf_event__repipe_sample(const struct perf_tool *tool, return perf_event__repipe_synth(tool, event); } +static int perf_event__convert_sample_callchain(const struct perf_tool *tool, + union perf_event *event, + struct perf_sample *sample, + struct evsel *evsel, + struct machine *machine) +{ + struct perf_inject *inject = container_of(tool, struct perf_inject, tool); + struct callchain_cursor *cursor = get_tls_callchain_cursor(); + union perf_event *event_copy = (void *)inject->event_copy; + struct callchain_cursor_node *node; + struct thread *thread; + u64 sample_type = evsel->core.attr.sample_type; + u32 sample_size = event->header.size; + u64 i, k; + int ret; + + if (event_copy == NULL) { + inject->event_copy = malloc(PERF_SAMPLE_MAX_SIZE); + if (!inject->event_copy) + return -ENOMEM; + + event_copy = (void *)inject->event_copy; + } + + if (cursor == NULL) + return -ENOMEM; + + callchain_cursor_reset(cursor); + + thread = machine__find_thread(machine, sample->tid, sample->pid); + if (thread == NULL) + goto out; + + /* this will parse DWARF using stack and register data */ + ret = thread__resolve_callchain(thread, cursor, evsel, sample, + /*parent=*/NULL, /*root_al=*/NULL, + PERF_MAX_STACK_DEPTH); + thread__put(thread); + if (ret != 0) + goto out; + + /* copy kernel callchain and context entries */ + for (i = 0; i < sample->callchain->nr; i++) { + inject->raw_callchain->ips[i] = sample->callchain->ips[i]; + if (sample->callchain->ips[i] == PERF_CONTEXT_USER) { + i++; + break; + } + } + if (i == 0 || inject->raw_callchain->ips[i - 1] != PERF_CONTEXT_USER) + inject->raw_callchain->ips[i++] = PERF_CONTEXT_USER; + + node = cursor->first; + for (k = 0; k < cursor->nr && i < PERF_MAX_STACK_DEPTH; k++) { + if (machine__kernel_ip(machine, node->ip)) + /* kernel IPs were added already */; + else if (node->ms.sym && node->ms.sym->inlined) + /* we can't handle inlined callchains */; + else + inject->raw_callchain->ips[i++] = node->ip; + + node = node->next; + } + + inject->raw_callchain->nr = i; + sample->callchain = inject->raw_callchain; + +out: + memcpy(event_copy, event, sizeof(event->header)); + + /* adjust sample size for stack and regs */ + sample_size -= sample->user_stack.size; + sample_size -= (hweight64(evsel->core.attr.sample_regs_user) + 1) * sizeof(u64); + sample_size += (sample->callchain->nr + 1) * sizeof(u64); + event_copy->header.size = sample_size; + + /* remove sample_type {STACK,REGS}_USER for synthesize */ + sample_type &= ~(PERF_SAMPLE_STACK_USER | PERF_SAMPLE_REGS_USER); + + perf_event__synthesize_sample(event_copy, sample_type, + evsel->core.attr.read_format, sample); + return perf_event__repipe_synth(tool, event_copy); +} + static struct dso *findnew_dso(int pid, int tid, const char *filename, const struct dso_id *id, struct machine *machine) { @@ -2270,6 +2356,15 @@ static int __cmd_inject(struct perf_inject *inject) /* Allow space in the header for guest attributes */ output_data_offset += gs->session->header.data_offset; output_data_offset = roundup(output_data_offset, 4096); + } else if (inject->convert_callchain) { + inject->tool.sample = perf_event__convert_sample_callchain; + inject->tool.fork = perf_event__repipe_fork; + inject->tool.comm = perf_event__repipe_comm; + inject->tool.exit = perf_event__repipe_exit; + inject->tool.mmap = perf_event__repipe_mmap; + inject->tool.mmap2 = perf_event__repipe_mmap2; + inject->tool.ordered_events = true; + inject->tool.ordering_requires_timestamps = true; } if (!inject->itrace_synth_opts.set) @@ -2322,6 +2417,23 @@ static int __cmd_inject(struct perf_inject *inject) perf_header__set_feat(&session->header, HEADER_BRANCH_STACK); } + + /* + * The converted data file won't have stack and registers. + * Update the perf_event_attr to remove them before writing. + */ + if (inject->convert_callchain) { + struct evsel *evsel; + + evlist__for_each_entry(session->evlist, evsel) { + evsel__reset_sample_bit(evsel, REGS_USER); + evsel__reset_sample_bit(evsel, STACK_USER); + evsel->core.attr.sample_regs_user = 0; + evsel->core.attr.sample_stack_user = 0; + evsel->core.attr.exclude_callchain_user = 0; + } + } + session->header.data_offset = output_data_offset; session->header.data_size = inject->bytes_written; perf_session__inject_header(session, session->evlist, fd, &inj_fc.fc, @@ -2346,6 +2458,18 @@ static int __cmd_inject(struct perf_inject *inject) return ret; } +static bool evsel__has_dwarf_callchain(struct evsel *evsel) +{ + struct perf_event_attr *attr = &evsel->core.attr; + const u64 dwarf_callchain_flags = + PERF_SAMPLE_STACK_USER | PERF_SAMPLE_REGS_USER | PERF_SAMPLE_CALLCHAIN; + + if (!attr->exclude_callchain_user) + return false; + + return (attr->sample_type & dwarf_callchain_flags) == dwarf_callchain_flags; +} + int cmd_inject(int argc, const char **argv) { struct perf_inject inject = { @@ -2414,6 +2538,8 @@ int cmd_inject(int argc, const char **argv) OPT_STRING(0, "guestmount", &symbol_conf.guestmount, "directory", "guest mount directory under which every guest os" " instance has a subdir"), + OPT_BOOLEAN(0, "convert-callchain", &inject.convert_callchain, + "Generate callchains using DWARF and drop register/stack data"), OPT_END() }; const char * const inject_usage[] = { @@ -2429,6 +2555,9 @@ int cmd_inject(int argc, const char **argv) #ifndef HAVE_JITDUMP set_option_nobuild(options, 'j', "jit", "NO_LIBELF=1", true); +#endif +#ifndef HAVE_LIBDW_SUPPORT + set_option_nobuild(options, 0, "convert-callchain", "NO_LIBDW=1", true); #endif argc = parse_options(argc, argv, options, inject_usage, 0); @@ -2588,6 +2717,28 @@ int cmd_inject(int argc, const char **argv) } } + if (inject.convert_callchain) { + struct evsel *evsel; + + if (inject.output.is_pipe || inject.session->data->is_pipe) { + pr_err("--convert-callchain cannot work with pipe\n"); + goto out_delete; + } + + evlist__for_each_entry(inject.session->evlist, evsel) { + if (!evsel__has_dwarf_callchain(evsel)) { + pr_err("--convert-callchain requires DWARF call graph.\n"); + goto out_delete; + } + } + + inject.raw_callchain = calloc(PERF_MAX_STACK_DEPTH, sizeof(u64)); + if (inject.raw_callchain == NULL) { + pr_err("callchain allocation failed\n"); + goto out_delete; + } + } + #ifdef HAVE_JITDUMP if (inject.jit_mode) { inject.tool.mmap2 = perf_event__repipe_mmap2; @@ -2618,5 +2769,6 @@ out_close_output: free(inject.itrace_synth_opts.vm_tm_corr_args); free(inject.event_copy); free(inject.guest_session.ev.event_buf); + free(inject.raw_callchain); return ret; }