// SPDX-License-Identifier: GPL-2.0
#include <errno.h>
#include <fcntl.h>
#include <inttypes.h>
#include <stdlib.h>
#include <perf/cpumap.h>

#include "cpumap.h"
#include "debug.h"
#include "event.h"
#include "evlist.h"
#include "evsel.h"
#include "thread_map.h"
#include "tests.h"
#include "util/affinity.h"
#include "util/mmap.h"
#include "util/sample.h"
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <perf/evlist.h>
#include <perf/mmap.h>

/*
 * This test will generate random numbers of calls to some getpid syscalls,
 * then establish an mmap for a group of events that are created to monitor
 * the syscalls.
 *
 * It will receive the events, using mmap, use its PERF_SAMPLE_ID generated
 * sample.id field to map back to its respective perf_evsel instance.
 *
 * Then it checks if the number of syscalls reported as perf events by
 * the kernel corresponds to the number of syscalls made.
 */
static int test__basic_mmap(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
{
        int err = TEST_FAIL;
        union perf_event *event;
        struct perf_thread_map *threads;
        struct perf_cpu_map *cpus;
        struct evlist *evlist;
        cpu_set_t cpu_set;
        const char *syscall_names[] = { "getsid", "getppid", "getpgid", };
        pid_t (*syscalls[])(void) = { (void *)getsid, getppid, (void*)getpgid };
#define nsyscalls ARRAY_SIZE(syscall_names)
        unsigned int nr_events[nsyscalls],
                     expected_nr_events[nsyscalls], i, j;
        struct evsel *evsels[nsyscalls], *evsel;
        char sbuf[STRERR_BUFSIZE];
        struct mmap *md;

        threads = thread_map__new_by_tid(getpid());
        if (threads == NULL) {
                pr_debug("thread_map__new\n");
                return -1;
        }

        cpus = perf_cpu_map__new_online_cpus();
        if (cpus == NULL) {
                pr_debug("perf_cpu_map__new\n");
                goto out_free_threads;
        }

        CPU_ZERO(&cpu_set);
        CPU_SET(perf_cpu_map__cpu(cpus, 0).cpu, &cpu_set);
        sched_setaffinity(0, sizeof(cpu_set), &cpu_set);
        if (sched_setaffinity(0, sizeof(cpu_set), &cpu_set) < 0) {
                pr_debug("sched_setaffinity() failed on CPU %d: %s ",
                         perf_cpu_map__cpu(cpus, 0).cpu,
                         str_error_r(errno, sbuf, sizeof(sbuf)));
                goto out_free_cpus;
        }

        evlist = evlist__new();
        if (evlist == NULL) {
                pr_debug("evlist__new\n");
                goto out_free_cpus;
        }

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

        for (i = 0; i < nsyscalls; ++i) {
                char name[64];

                snprintf(name, sizeof(name), "sys_enter_%s", syscall_names[i]);
                evsels[i] = evsel__newtp("syscalls", name);
                if (IS_ERR(evsels[i])) {
                        pr_debug("evsel__new(%s)\n", name);
                        if (PTR_ERR(evsels[i]) == -EACCES) {
                                /* Permissions failure, flag the failure as a skip. */
                                err = TEST_SKIP;
                        }
                        goto out_delete_evlist;
                }

                evsels[i]->core.attr.wakeup_events = 1;
                evsel__set_sample_id(evsels[i], false);

                evlist__add(evlist, evsels[i]);

                if (evsel__open(evsels[i], cpus, threads) < 0) {
                        pr_debug("failed to open counter: %s, "
                                 "tweak /proc/sys/kernel/perf_event_paranoid?\n",
                                 str_error_r(errno, sbuf, sizeof(sbuf)));
                        goto out_delete_evlist;
                }

                nr_events[i] = 0;
                expected_nr_events[i] = 1 + rand() % 127;
        }

        if (evlist__mmap(evlist, 128) < 0) {
                pr_debug("failed to mmap events: %d (%s)\n", errno,
                         str_error_r(errno, sbuf, sizeof(sbuf)));
                goto out_delete_evlist;
        }

        for (i = 0; i < nsyscalls; ++i)
                for (j = 0; j < expected_nr_events[i]; ++j) {
                        syscalls[i]();
                }

        md = &evlist->mmap[0];
        if (perf_mmap__read_init(&md->core) < 0)
                goto out_init;

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

                if (event->header.type != PERF_RECORD_SAMPLE) {
                        pr_debug("unexpected %s event\n",
                                 perf_event__name(event->header.type));
                        goto out_delete_evlist;
                }

                perf_sample__init(&sample, /*all=*/false);
                err = evlist__parse_sample(evlist, event, &sample);
                if (err) {
                        pr_err("Can't parse sample, err = %d\n", err);
                        perf_sample__exit(&sample);
                        goto out_delete_evlist;
                }

                err = -1;
                evsel = evlist__id2evsel(evlist, sample.id);
                perf_sample__exit(&sample);
                if (evsel == NULL) {
                        pr_debug("event with id %" PRIu64
                                 " doesn't map to an evsel\n", sample.id);
                        goto out_delete_evlist;
                }
                nr_events[evsel->core.idx]++;
                perf_mmap__consume(&md->core);
        }
        perf_mmap__read_done(&md->core);

out_init:
        err = 0;
        evlist__for_each_entry(evlist, evsel) {
                if (nr_events[evsel->core.idx] != expected_nr_events[evsel->core.idx]) {
                        pr_debug("expected %d %s events, got %d\n",
                                 expected_nr_events[evsel->core.idx],
                                 evsel__name(evsel), nr_events[evsel->core.idx]);
                        err = -1;
                        goto out_delete_evlist;
                }
        }

out_delete_evlist:
        evlist__delete(evlist);
out_free_cpus:
        perf_cpu_map__put(cpus);
out_free_threads:
        perf_thread_map__put(threads);
        return err;
}

enum user_read_state {
        USER_READ_ENABLED,
        USER_READ_DISABLED,
        USER_READ_UNKNOWN,
};

static enum user_read_state set_user_read(struct perf_pmu *pmu, enum user_read_state enabled)
{
        char buf[2] = {0, '\n'};
        ssize_t len;
        int events_fd, rdpmc_fd;
        enum user_read_state old_user_read = USER_READ_UNKNOWN;

        if (enabled == USER_READ_UNKNOWN)
                return USER_READ_UNKNOWN;

        events_fd = perf_pmu__event_source_devices_fd();
        if (events_fd < 0)
                return USER_READ_UNKNOWN;

        rdpmc_fd = perf_pmu__pathname_fd(events_fd, pmu->name, "rdpmc", O_RDWR);
        if (rdpmc_fd < 0) {
                close(events_fd);
                return USER_READ_UNKNOWN;
        }

        len = read(rdpmc_fd, buf, sizeof(buf));
        if (len != sizeof(buf))
                pr_debug("%s read failed\n", __func__);

        // Note, on Intel hybrid disabling on 1 PMU will implicitly disable on
        // all the core PMUs.
        old_user_read = (buf[0] == '1') ? USER_READ_ENABLED : USER_READ_DISABLED;

        if (enabled != old_user_read) {
                buf[0] = (enabled == USER_READ_ENABLED) ? '1' : '0';
                len = write(rdpmc_fd, buf, sizeof(buf));
                if (len != sizeof(buf))
                        pr_debug("%s write failed\n", __func__);
        }
        close(rdpmc_fd);
        close(events_fd);
        return old_user_read;
}

static int test_stat_user_read(u64 event, enum user_read_state enabled)
{
        struct perf_pmu *pmu = NULL;
        struct perf_thread_map *threads = perf_thread_map__new_dummy();
        int ret = TEST_OK;

        pr_err("User space counter reading %" PRIu64 "\n", event);
        if (!threads) {
                pr_err("User space counter reading [Failed to create threads]\n");
                return TEST_FAIL;
        }
        perf_thread_map__set_pid(threads, 0, 0);

        while ((pmu = perf_pmus__scan_core(pmu)) != NULL) {
                enum user_read_state saved_user_read_state = set_user_read(pmu, enabled);
                struct perf_event_attr attr = {
                        .type   = PERF_TYPE_HARDWARE,
                        .config = perf_pmus__supports_extended_type()
                        ? event | ((u64)pmu->type << PERF_PMU_TYPE_SHIFT)
                                : event,
#ifdef __aarch64__
                        .config1 = 0x2,         /* Request user access */
#endif
                };
                struct perf_evsel *evsel = NULL;
                int err;
                struct perf_event_mmap_page *pc;
                bool mapped = false, opened = false, rdpmc_supported;
                struct perf_counts_values counts = { .val = 0 };


                pr_debug("User space counter reading for PMU %s\n", pmu->name);
                /*
                 * Restrict scheduling to only use the rdpmc on the CPUs the
                 * event can be on. If the test doesn't run on the CPU of the
                 * event then the event will be disabled and the pc->index test
                 * will fail.
                 */
                if (pmu->cpus != NULL)
                        cpu_map__set_affinity(pmu->cpus);

                /* Make the evsel. */
                evsel = perf_evsel__new(&attr);
                if (!evsel) {
                        pr_err("User space counter reading for PMU %s [Failed to allocate evsel]\n",
                                pmu->name);
                        ret = TEST_FAIL;
                        goto cleanup;
                }

                err = perf_evsel__open(evsel, NULL, threads);
                if (err) {
                        pr_err("User space counter reading for PMU %s [Failed to open evsel]\n",
                                pmu->name);
                        ret = TEST_SKIP;
                        goto cleanup;
                }
                opened = true;
                err = perf_evsel__mmap(evsel, 0);
                if (err) {
                        pr_err("User space counter reading for PMU %s [Failed to mmap evsel]\n",
                                pmu->name);
                        ret = TEST_FAIL;
                        goto cleanup;
                }
                mapped = true;

                pc = perf_evsel__mmap_base(evsel, 0, 0);
                if (!pc) {
                        pr_err("User space counter reading for PMU %s [Failed to get mmaped address]\n",
                                pmu->name);
                        ret = TEST_FAIL;
                        goto cleanup;
                }

                if (saved_user_read_state == USER_READ_UNKNOWN)
                        rdpmc_supported = pc->cap_user_rdpmc && pc->index;
                else
                        rdpmc_supported = (enabled == USER_READ_ENABLED);

                if (rdpmc_supported && (!pc->cap_user_rdpmc || !pc->index)) {
                        pr_err("User space counter reading for PMU %s [Failed unexpected supported counter access %d %d]\n",
                                pmu->name, pc->cap_user_rdpmc, pc->index);
                        ret = TEST_FAIL;
                        goto cleanup;
                }

                if (!rdpmc_supported && pc->cap_user_rdpmc) {
                        pr_err("User space counter reading for PMU %s [Failed unexpected unsupported counter access %d]\n",
                                pmu->name, pc->cap_user_rdpmc);
                        ret = TEST_FAIL;
                        goto cleanup;
                }

                if (rdpmc_supported && pc->pmc_width < 32) {
                        pr_err("User space counter reading for PMU %s [Failed width not set %d]\n",
                                pmu->name, pc->pmc_width);
                        ret = TEST_FAIL;
                        goto cleanup;
                }

                perf_evsel__read(evsel, 0, 0, &counts);
                if (rdpmc_supported && counts.val == 0) {
                        pr_err("User space counter reading for PMU %s [Failed read]\n", pmu->name);
                        ret = TEST_FAIL;
                        goto cleanup;
                }

                for (int i = 0; i < 5; i++) {
                        volatile int count = 0x10000 << i;
                        __u64 start, end, last = 0;

                        pr_debug("\tloop = %u, ", count);

                        perf_evsel__read(evsel, 0, 0, &counts);
                        start = counts.val;

                        while (count--) ;

                        perf_evsel__read(evsel, 0, 0, &counts);
                        end = counts.val;

                        if ((end - start) < last) {
                                pr_err("User space counter reading for PMU %s [Failed invalid counter data: end=%llu start=%llu last= %llu]\n",
                                        pmu->name, end, start, last);
                                ret = TEST_FAIL;
                                goto cleanup;
                        }
                        last = end - start;
                        pr_debug("count = %llu\n", last);
                }
                pr_debug("User space counter reading for PMU %s [Success]\n", pmu->name);
cleanup:
                if (mapped)
                        perf_evsel__munmap(evsel);
                if (opened)
                        perf_evsel__close(evsel);
                perf_evsel__delete(evsel);

                /* If the affinity was changed, then put it back to all CPUs. */
                if (pmu->cpus != NULL) {
                        struct perf_cpu_map *cpus = cpu_map__online();

                        cpu_map__set_affinity(cpus);
                        perf_cpu_map__put(cpus);
                }
                set_user_read(pmu, saved_user_read_state);
        }
        perf_thread_map__put(threads);
        return ret;
}

static int test__mmap_user_read_instr(struct test_suite *test __maybe_unused,
                                      int subtest __maybe_unused)
{
        return test_stat_user_read(PERF_COUNT_HW_INSTRUCTIONS, USER_READ_ENABLED);
}

static int test__mmap_user_read_cycles(struct test_suite *test __maybe_unused,
                                       int subtest __maybe_unused)
{
        return test_stat_user_read(PERF_COUNT_HW_CPU_CYCLES, USER_READ_ENABLED);
}

static int test__mmap_user_read_instr_disabled(struct test_suite *test __maybe_unused,
                                               int subtest __maybe_unused)
{
        return test_stat_user_read(PERF_COUNT_HW_INSTRUCTIONS, USER_READ_DISABLED);
}

static int test__mmap_user_read_cycles_disabled(struct test_suite *test __maybe_unused,
                                                int subtest __maybe_unused)
{
        return test_stat_user_read(PERF_COUNT_HW_CPU_CYCLES, USER_READ_DISABLED);
}

static struct test_case tests__basic_mmap[] = {
        TEST_CASE_REASON("Read samples using the mmap interface",
                         basic_mmap,
                         "permissions"),
        TEST_CASE_REASON_EXCLUSIVE("User space counter reading of instructions",
                         mmap_user_read_instr,
#if defined(__i386__) || defined(__x86_64__) || defined(__aarch64__) || \
                         (defined(__riscv) && __riscv_xlen == 64)
                         "permissions"
#else
                         "unsupported"
#endif
                ),
        TEST_CASE_REASON_EXCLUSIVE("User space counter reading of cycles",
                         mmap_user_read_cycles,
#if defined(__i386__) || defined(__x86_64__) || defined(__aarch64__) || \
                         (defined(__riscv) && __riscv_xlen == 64)
                         "permissions"
#else
                         "unsupported"
#endif
                ),
        TEST_CASE_REASON_EXCLUSIVE("User space counter disabling instructions",
                         mmap_user_read_instr_disabled,
#if defined(__i386__) || defined(__x86_64__) || defined(__aarch64__) || \
                         (defined(__riscv) && __riscv_xlen == 64)
                         "permissions"
#else
                         "unsupported"
#endif
                ),
        TEST_CASE_REASON_EXCLUSIVE("User space counter disabling cycles",
                         mmap_user_read_cycles_disabled,
#if defined(__i386__) || defined(__x86_64__) || defined(__aarch64__) || \
                         (defined(__riscv) && __riscv_xlen == 64)
                         "permissions"
#else
                         "unsupported"
#endif
                ),
        {       .name = NULL, }
};

struct test_suite suite__basic_mmap = {
        .desc = "mmap interface tests",
        .test_cases = tests__basic_mmap,
};