// SPDX-License-Identifier: GPL-2.0
#include <errno.h>
#include <inttypes.h>
#include <limits.h>
#include <stdbool.h>
#include <stdio.h>
#include <unistd.h>
#include <linux/types.h>
#include <sys/prctl.h>
#include <perf/cpumap.h>
#include <perf/evlist.h>
#include <perf/mmap.h>

#include "debug.h"
#include "parse-events.h"
#include "evlist.h"
#include "evsel.h"
#include "thread_map.h"
#include "record.h"
#include "tsc.h"
#include "mmap.h"
#include "tests.h"
#include "util/sample.h"

/*
 * Except x86_64/i386 and Arm64, other archs don't support TSC in perf.  Just
 * enable the test for x86_64/i386 and Arm64 archs.
 */
#if defined(__x86_64__) || defined(__i386__) || defined(__aarch64__)
#define TSC_IS_SUPPORTED 1
#else
#define TSC_IS_SUPPORTED 0
#endif

#define CHECK__(x) {                            \
        while ((x) < 0) {                       \
                pr_debug(#x " failed!\n");      \
                goto out_err;                   \
        }                                       \
}

#define CHECK_NOT_NULL__(x) {                   \
        while ((x) == NULL) {                   \
                pr_debug(#x " failed!\n");      \
                goto out_err;                   \
        }                                       \
}

static int test__tsc_is_supported(struct test_suite *test __maybe_unused,
                                  int subtest __maybe_unused)
{
        if (!TSC_IS_SUPPORTED) {
                pr_debug("Test not supported on this architecture\n");
                return TEST_SKIP;
        }

        return TEST_OK;
}

/**
 * test__perf_time_to_tsc - test converting perf time to TSC.
 *
 * This function implements a test that checks that the conversion of perf time
 * to and from TSC is consistent with the order of events.  If the test passes
 * %0 is returned, otherwise %-1 is returned.  If TSC conversion is not
 * supported then the test passes but " (not supported)" is printed.
 */
static int test__perf_time_to_tsc(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
{
        struct record_opts opts = {
                .mmap_pages          = UINT_MAX,
                .user_freq           = UINT_MAX,
                .user_interval       = ULLONG_MAX,
                .target              = {
                        .uses_mmap   = true,
                },
                .sample_time         = true,
        };
        struct perf_thread_map *threads = NULL;
        struct perf_cpu_map *cpus = NULL;
        struct evlist *evlist = NULL;
        struct evsel *evsel = NULL;
        int err = TEST_FAIL, ret, i;
        const char *comm1, *comm2;
        struct perf_tsc_conversion tc;
        struct perf_event_mmap_page *pc;
        union perf_event *event;
        u64 test_tsc, comm1_tsc, comm2_tsc;
        u64 test_time, comm1_time = 0, comm2_time = 0;
        struct mmap *md;


        threads = thread_map__new_by_tid(getpid());
        CHECK_NOT_NULL__(threads);

        cpus = perf_cpu_map__new_online_cpus();
        CHECK_NOT_NULL__(cpus);

        evlist = evlist__new();
        CHECK_NOT_NULL__(evlist);

        perf_evlist__set_maps(&evlist->core, cpus, threads);

        CHECK__(parse_event(evlist, "cpu-cycles:u"));

        evlist__config(evlist, &opts, NULL);

        /* For hybrid "cpu-cycles:u", it creates two events */
        evlist__for_each_entry(evlist, evsel) {
                evsel->core.attr.comm = 1;
                evsel->core.attr.disabled = 1;
                evsel->core.attr.enable_on_exec = 0;
        }

        ret = evlist__open(evlist);
        if (ret < 0) {
                if (ret == -ENOENT)
                        err = TEST_SKIP;
                else
                        pr_debug("evlist__open() failed\n");
                goto out_err;
        }

        CHECK__(evlist__mmap(evlist, UINT_MAX));

        pc = evlist->mmap[0].core.base;
        ret = perf_read_tsc_conversion(pc, &tc);
        if (ret) {
                if (ret == -EOPNOTSUPP) {
                        pr_debug("perf_read_tsc_conversion is not supported in current kernel\n");
                        err = TEST_SKIP;
                }
                goto out_err;
        }

        evlist__enable(evlist);

        comm1 = "Test COMM 1";
        CHECK__(prctl(PR_SET_NAME, (unsigned long)comm1, 0, 0, 0));

        test_tsc = rdtsc();

        comm2 = "Test COMM 2";
        CHECK__(prctl(PR_SET_NAME, (unsigned long)comm2, 0, 0, 0));

        evlist__disable(evlist);

        for (i = 0; i < evlist->core.nr_mmaps; i++) {
                md = &evlist->mmap[i];
                if (perf_mmap__read_init(&md->core) < 0)
                        continue;

                while ((event = perf_mmap__read_event(&md->core)) != NULL) {
                        struct perf_sample sample;

                        perf_sample__init(&sample, /*all=*/false);
                        if (event->header.type != PERF_RECORD_COMM ||
                            (pid_t)event->comm.pid != getpid() ||
                            (pid_t)event->comm.tid != getpid())
                                goto next_event;

                        if (strcmp(event->comm.comm, comm1) == 0) {
                                CHECK_NOT_NULL__(evsel = evlist__event2evsel(evlist, event));
                                CHECK__(evsel__parse_sample(evsel, event, &sample));
                                comm1_time = sample.time;
                        }
                        if (strcmp(event->comm.comm, comm2) == 0) {
                                CHECK_NOT_NULL__(evsel = evlist__event2evsel(evlist, event));
                                CHECK__(evsel__parse_sample(evsel, event, &sample));
                                comm2_time = sample.time;
                        }
next_event:
                        perf_mmap__consume(&md->core);
                        perf_sample__exit(&sample);
                }
                perf_mmap__read_done(&md->core);
        }

        if (!comm1_time || !comm2_time)
                goto out_err;

        test_time = tsc_to_perf_time(test_tsc, &tc);
        comm1_tsc = perf_time_to_tsc(comm1_time, &tc);
        comm2_tsc = perf_time_to_tsc(comm2_time, &tc);

        pr_debug("1st event perf time %"PRIu64" tsc %"PRIu64"\n",
                 comm1_time, comm1_tsc);
        pr_debug("rdtsc          time %"PRIu64" tsc %"PRIu64"\n",
                 test_time, test_tsc);
        pr_debug("2nd event perf time %"PRIu64" tsc %"PRIu64"\n",
                 comm2_time, comm2_tsc);

        if (test_time <= comm1_time ||
            test_time >= comm2_time)
                goto out_err;

        if (test_tsc <= comm1_tsc ||
            test_tsc >= comm2_tsc)
                goto out_err;

        err = TEST_OK;

out_err:
        evlist__delete(evlist);
        perf_cpu_map__put(cpus);
        perf_thread_map__put(threads);
        return err;
}

static struct test_case time_to_tsc_tests[] = {
        TEST_CASE_REASON("TSC support", tsc_is_supported,
                         "This architecture does not support"),
        TEST_CASE_REASON("Perf time to TSC", perf_time_to_tsc,
                         "perf_read_tsc_conversion is not supported"),
        { .name = NULL, }
};

struct test_suite suite__perf_time_to_tsc = {
        .desc = "Convert perf time to TSC",
        .test_cases = time_to_tsc_tests,
};