root/tools/perf/builtin-evlist.c
// SPDX-License-Identifier: GPL-2.0
/*
 * Builtin evlist command: Show the list of event selectors present
 * in a perf.data file.
 */
#include "builtin.h"

#include <linux/list.h>

#include "util/evlist.h"
#include "util/evsel.h"
#include "util/evsel_fprintf.h"
#include "util/parse-events.h"
#include <subcmd/parse-options.h>
#include "util/session.h"
#include "util/data.h"
#include "util/debug.h"
#include <linux/err.h>
#include "util/tool.h"
#include "util/util.h"

static int process_header_feature(const struct perf_tool *tool __maybe_unused,
                                  struct perf_session *session __maybe_unused,
                                  union perf_event *event __maybe_unused)
{
        session_done = 1;
        return 0;
}

static int __cmd_evlist(const char *file_name, struct perf_attr_details *details)
{
        struct perf_session *session;
        struct evsel *pos;
        struct perf_data data = {
                .path      = file_name,
                .mode      = PERF_DATA_MODE_READ,
                .force     = details->force,
        };
        struct perf_tool tool;
        bool has_tracepoint = false, has_group = false;

        perf_tool__init(&tool, /*ordered_events=*/false);
        /* only needed for pipe mode */
        tool.attr = perf_event__process_attr;
        tool.feature = process_header_feature;
        session = perf_session__new(&data, &tool);
        if (IS_ERR(session))
                return PTR_ERR(session);

        if (data.is_pipe)
                perf_session__process_events(session);

        evlist__for_each_entry(session->evlist, pos) {
                evsel__fprintf(pos, details, stdout);

                if (pos->core.attr.type == PERF_TYPE_TRACEPOINT)
                        has_tracepoint = true;

                if (!evsel__is_group_leader(pos))
                        has_group = true;
        }

        if (has_tracepoint && !details->trace_fields)
                printf("# Tip: use 'perf evlist --trace-fields' to show fields for tracepoint events\n");

        if (has_group && !details->event_group)
                printf("# Tip: use 'perf evlist -g' to show group information\n");

        perf_session__delete(session);
        return 0;
}

int cmd_evlist(int argc, const char **argv)
{
        struct perf_attr_details details = { .verbose = false, };
        const struct option options[] = {
        OPT_STRING('i', "input", &input_name, "file", "Input file name"),
        OPT_BOOLEAN('F', "freq", &details.freq, "Show the sample frequency"),
        OPT_BOOLEAN('v', "verbose", &details.verbose,
                    "Show all event attr details"),
        OPT_BOOLEAN('g', "group", &details.event_group,
                    "Show event group information"),
        OPT_BOOLEAN('f', "force", &details.force, "don't complain, do it"),
        OPT_BOOLEAN(0, "trace-fields", &details.trace_fields, "Show tracepoint fields"),
        OPT_END()
        };
        const char * const evlist_usage[] = {
                "perf evlist [<options>]",
                NULL
        };

        argc = parse_options(argc, argv, options, evlist_usage, 0);
        if (argc)
                usage_with_options(evlist_usage, options);

        if (details.event_group && (details.verbose || details.freq)) {
                usage_with_options_msg(evlist_usage, options,
                        "--group option is not compatible with other options\n");
        }

        return __cmd_evlist(input_name, &details);
}