/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright (c) 2024 Meta Platforms, Inc. and affiliates.
 * Copyright (c) 2024 David Vernet <dvernet@meta.com>
 */
#include <bpf/bpf.h>
#include <sched.h>
#include <scx/common.h>
#include <sys/wait.h>
#include <unistd.h>
#include "exit.bpf.skel.h"
#include "scx_test.h"

#include "exit_test.h"

static enum scx_test_status run(void *ctx)
{
        enum exit_test_case tc;

        for (tc = 0; tc < NUM_EXITS; tc++) {
                struct exit *skel;
                struct bpf_link *link;
                char buf[16];

                /*
                 * On single-CPU systems, ops.select_cpu() is never
                 * invoked, so skip this test to avoid getting stuck
                 * indefinitely.
                 */
                if (tc == EXIT_SELECT_CPU && libbpf_num_possible_cpus() == 1)
                        continue;

                skel = exit__open();
                SCX_ENUM_INIT(skel);
                skel->rodata->exit_point = tc;
                exit__load(skel);
                link = bpf_map__attach_struct_ops(skel->maps.exit_ops);
                if (!link) {
                        SCX_ERR("Failed to attach scheduler");
                        exit__destroy(skel);
                        return SCX_TEST_FAIL;
                }

                /* Assumes uei.kind is written last */
                while (skel->data->uei.kind == EXIT_KIND(SCX_EXIT_NONE))
                        sched_yield();

                SCX_EQ(skel->data->uei.kind, EXIT_KIND(SCX_EXIT_UNREG_BPF));
                SCX_EQ(skel->data->uei.exit_code, tc);
                sprintf(buf, "%d", tc);
                SCX_ASSERT(!strcmp(skel->data->uei.msg, buf));
                bpf_link__destroy(link);
                exit__destroy(skel);
        }

        return SCX_TEST_PASS;
}

struct scx_test exit_test = {
        .name = "exit",
        .description = "Verify we can cleanly exit a scheduler in multiple places",
        .run = run,
};
REGISTER_SCX_TEST(&exit_test)