// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2021. Huawei Technologies Co., Ltd */
#include <argp.h>
#include "bench.h"
#include "strncmp_bench.skel.h"

static struct strncmp_ctx {
        struct strncmp_bench *skel;
} ctx;

static struct strncmp_args {
        u32 cmp_str_len;
} args = {
        .cmp_str_len = 32,
};

enum {
        ARG_CMP_STR_LEN = 5000,
};

static const struct argp_option opts[] = {
        { "cmp-str-len", ARG_CMP_STR_LEN, "CMP_STR_LEN", 0,
          "Set the length of compared string" },
        {},
};

static error_t strncmp_parse_arg(int key, char *arg, struct argp_state *state)
{
        switch (key) {
        case ARG_CMP_STR_LEN:
                args.cmp_str_len = strtoul(arg, NULL, 10);
                if (!args.cmp_str_len ||
                    args.cmp_str_len >= sizeof(ctx.skel->bss->str)) {
                        fprintf(stderr, "Invalid cmp str len (limit %zu)\n",
                                sizeof(ctx.skel->bss->str));
                        argp_usage(state);
                }
                break;
        default:
                return ARGP_ERR_UNKNOWN;
        }

        return 0;
}

const struct argp bench_strncmp_argp = {
        .options = opts,
        .parser = strncmp_parse_arg,
};

static void strncmp_validate(void)
{
        if (env.consumer_cnt != 0) {
                fprintf(stderr, "strncmp benchmark doesn't support consumer!\n");
                exit(1);
        }
}

static void strncmp_setup(void)
{
        int err;
        char *target;
        size_t i, sz;

        sz = sizeof(ctx.skel->rodata->target);
        if (!sz || sz < sizeof(ctx.skel->bss->str)) {
                fprintf(stderr, "invalid string size (target %zu, src %zu)\n",
                        sz, sizeof(ctx.skel->bss->str));
                exit(1);
        }

        setup_libbpf();

        ctx.skel = strncmp_bench__open();
        if (!ctx.skel) {
                fprintf(stderr, "failed to open skeleton\n");
                exit(1);
        }

        srandom(time(NULL));
        target = ctx.skel->rodata->target;
        for (i = 0; i < sz - 1; i++)
                target[i] = '1' + random() % 9;
        target[sz - 1] = '\0';

        ctx.skel->rodata->cmp_str_len = args.cmp_str_len;

        memcpy(ctx.skel->bss->str, target, args.cmp_str_len);
        ctx.skel->bss->str[args.cmp_str_len] = '\0';
        /* Make bss->str < rodata->target */
        ctx.skel->bss->str[args.cmp_str_len - 1] -= 1;

        err = strncmp_bench__load(ctx.skel);
        if (err) {
                fprintf(stderr, "failed to load skeleton\n");
                strncmp_bench__destroy(ctx.skel);
                exit(1);
        }
}

static void strncmp_attach_prog(struct bpf_program *prog)
{
        struct bpf_link *link;

        link = bpf_program__attach(prog);
        if (!link) {
                fprintf(stderr, "failed to attach program!\n");
                exit(1);
        }
}

static void strncmp_no_helper_setup(void)
{
        strncmp_setup();
        strncmp_attach_prog(ctx.skel->progs.strncmp_no_helper);
}

static void strncmp_helper_setup(void)
{
        strncmp_setup();
        strncmp_attach_prog(ctx.skel->progs.strncmp_helper);
}

static void *strncmp_producer(void *ctx)
{
        while (true)
                (void)syscall(__NR_getpgid);
        return NULL;
}

static void strncmp_measure(struct bench_res *res)
{
        res->hits = atomic_swap(&ctx.skel->bss->hits, 0);
}

const struct bench bench_strncmp_no_helper = {
        .name = "strncmp-no-helper",
        .argp = &bench_strncmp_argp,
        .validate = strncmp_validate,
        .setup = strncmp_no_helper_setup,
        .producer_thread = strncmp_producer,
        .measure = strncmp_measure,
        .report_progress = hits_drops_report_progress,
        .report_final = hits_drops_report_final,
};

const struct bench bench_strncmp_helper = {
        .name = "strncmp-helper",
        .argp = &bench_strncmp_argp,
        .validate = strncmp_validate,
        .setup = strncmp_helper_setup,
        .producer_thread = strncmp_producer,
        .measure = strncmp_measure,
        .report_progress = hits_drops_report_progress,
        .report_final = hits_drops_report_final,
};