// SPDX-License-Identifier: GPL-2.0
#include <inttypes.h>
#include <unistd.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <pthread.h>
#include <stdlib.h>
#include <stdio.h>
#include "debug.h"
#include "tests.h"
#include "machine.h"
#include "thread_map.h"
#include "symbol.h"
#include "thread.h"
#include "util.h"

#define THREADS 4

static int go_away;

struct thread_data {
        pthread_t       pt;
        pid_t           tid;
        void            *map;
        int             ready[2];
};

static struct thread_data threads[THREADS];

static int thread_init(struct thread_data *td)
{
        void *map;

        map = mmap(NULL, page_size,
                   PROT_READ|PROT_WRITE|PROT_EXEC,
                   MAP_SHARED|MAP_ANONYMOUS, -1, 0);

        if (map == MAP_FAILED) {
                perror("mmap failed");
                return -1;
        }

        td->map = map;
        td->tid = syscall(SYS_gettid);

        pr_debug("tid = %d, map = %p\n", td->tid, map);
        return 0;
}

static void *thread_fn(void *arg)
{
        struct thread_data *td = arg;
        ssize_t ret;
        int go;

        if (thread_init(td))
                return NULL;

        /* Signal thread_create thread is initialized. */
        ret = write(td->ready[1], &go, sizeof(int));
        if (ret != sizeof(int)) {
                pr_err("failed to notify\n");
                return NULL;
        }

        while (!go_away) {
                /* Waiting for main thread to kill us. */
                usleep(100);
        }

        munmap(td->map, page_size);
        return NULL;
}

static int thread_create(int i)
{
        struct thread_data *td = &threads[i];
        int err, go;

        if (pipe(td->ready))
                return -1;

        err = pthread_create(&td->pt, NULL, thread_fn, td);
        if (!err) {
                /* Wait for thread initialization. */
                ssize_t ret = read(td->ready[0], &go, sizeof(int));
                err = ret != sizeof(int);
        }

        close(td->ready[0]);
        close(td->ready[1]);
        return err;
}

static int threads_create(void)
{
        struct thread_data *td0 = &threads[0];
        int i, err = 0;

        go_away = 0;

        /* 0 is main thread */
        if (thread_init(td0))
                return -1;

        for (i = 1; !err && i < THREADS; i++)
                err = thread_create(i);

        return err;
}

static int threads_destroy(void)
{
        struct thread_data *td0 = &threads[0];
        int i, err = 0;

        /* cleanup the main thread */
        munmap(td0->map, page_size);

        go_away = 1;

        for (i = 1; !err && i < THREADS; i++)
                err = pthread_join(threads[i].pt, NULL);

        return err;
}

typedef int (*synth_cb)(struct machine *machine);

static int synth_all(struct machine *machine)
{
        return perf_event__synthesize_threads(NULL,
                                              perf_event__process,
                                              machine, 0, 500, 1);
}

static int synth_process(struct machine *machine)
{
        struct thread_map *map;
        int err;

        map = thread_map__new_by_pid(getpid());

        err = perf_event__synthesize_thread_map(NULL, map,
                                                perf_event__process,
                                                machine, 0, 500);

        thread_map__put(map);
        return err;
}

static int mmap_events(synth_cb synth)
{
        struct machine *machine;
        int err, i;

        /*
         * The threads_create will not return before all threads
         * are spawned and all created memory map.
         *
         * They will loop until threads_destroy is called, so we
         * can safely run synthesizing function.
         */
        TEST_ASSERT_VAL("failed to create threads", !threads_create());

        machine = machine__new_host();

        dump_trace = verbose > 1 ? 1 : 0;

        err = synth(machine);

        dump_trace = 0;

        TEST_ASSERT_VAL("failed to destroy threads", !threads_destroy());
        TEST_ASSERT_VAL("failed to synthesize maps", !err);

        /*
         * All data is synthesized, try to find map for each
         * thread object.
         */
        for (i = 0; i < THREADS; i++) {
                struct thread_data *td = &threads[i];
                struct addr_location al;
                struct thread *thread;

                thread = machine__findnew_thread(machine, getpid(), td->tid);

                pr_debug("looking for map %p\n", td->map);

                thread__find_addr_map(thread,
                                      PERF_RECORD_MISC_USER, MAP__FUNCTION,
                                      (unsigned long) (td->map + 1), &al);

                thread__put(thread);

                if (!al.map) {
                        pr_debug("failed, couldn't find map\n");
                        err = -1;
                        break;
                }

                pr_debug("map %p, addr %" PRIx64 "\n", al.map, al.map->start);
        }

        machine__delete_threads(machine);
        machine__delete(machine);
        return err;
}

/*
 * This test creates 'THREADS' number of threads (including
 * main thread) and each thread creates memory map.
 *
 * When threads are created, we synthesize them with both
 * (separate tests):
 *   perf_event__synthesize_thread_map (process based)
 *   perf_event__synthesize_threads    (global)
 *
 * We test we can find all memory maps via:
 *   thread__find_addr_map
 *
 * by using all thread objects.
 */
int test__mmap_thread_lookup(struct test *test __maybe_unused, int subtest __maybe_unused)
{
        /* perf_event__synthesize_threads synthesize */
        TEST_ASSERT_VAL("failed with sythesizing all",
                        !mmap_events(synth_all));

        /* perf_event__synthesize_thread_map synthesize */
        TEST_ASSERT_VAL("failed with sythesizing process",
                        !mmap_events(synth_process));

        return 0;
}