hakmem/core/box/tiny_class_policy_box.c

// tiny_class_policy_box.c - Initialization of per-class Tiny policy table

#include "tiny_class_policy_box.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>

TinyClassPolicy g_tiny_class_policy[TINY_NUM_CLASSES];
static _Atomic int g_tiny_class_policy_init_done = 0;
static _Atomic int g_tiny_class_policy_logged = 0;

static inline TinyClassPolicy tiny_class_policy_default_entry(void) {
    TinyClassPolicy p = {0};
    p.page_box_enabled = 0;
    p.warm_enabled = 0;
    p.warm_cap = 0;
    return p;
}

static void tiny_class_policy_set_legacy(void) {
    TinyClassPolicy def = tiny_class_policy_default_entry();
    for (int i = 0; i < TINY_NUM_CLASSES; i++) {
        g_tiny_class_policy[i] = def;
    }

    // legacy: Page Box は C5–C7、Warm は全クラス ON（C0–C4 は控えめ cap）
    for (int i = 0; i < TINY_NUM_CLASSES; i++) {
        g_tiny_class_policy[i].warm_enabled = 1;
        g_tiny_class_policy[i].warm_cap = (i < 5) ? 4 : 8;
    }
    for (int i = 5; i < TINY_NUM_CLASSES; i++) {
        g_tiny_class_policy[i].page_box_enabled = 1;
    }
}

static void tiny_class_policy_set_c5_7_only(void) {
    TinyClassPolicy def = tiny_class_policy_default_entry();
    for (int i = 0; i < TINY_NUM_CLASSES; i++) {
        g_tiny_class_policy[i] = def;
    }
    for (int i = 5; i < TINY_NUM_CLASSES; i++) {
        g_tiny_class_policy[i].page_box_enabled = 1;
        g_tiny_class_policy[i].warm_enabled = 1;
        g_tiny_class_policy[i].warm_cap = 8;
    }
}

static void tiny_class_policy_set_tinyplus_all(void) {
    // いまは legacy と同じ挙動でエントリを用意しておく。
    tiny_class_policy_set_legacy();
}

static const char* tiny_class_policy_set_profile(const char* profile) {
    if (profile == NULL || *profile == '\0' || strcasecmp(profile, "legacy") == 0) {
        tiny_class_policy_set_legacy();
        return "legacy";
    } else if (strcasecmp(profile, "c5_7_only") == 0) {
        tiny_class_policy_set_c5_7_only();
        return "c5_7_only";
    } else if (strcasecmp(profile, "tinyplus_all") == 0) {
        tiny_class_policy_set_tinyplus_all();
        return "tinyplus_all";
    } else {
        // 不明な値は安全側で legacy にフォールバック。
        tiny_class_policy_set_legacy();
        return "legacy";
    }
}

void tiny_class_policy_init_once(void) {
    if (atomic_load_explicit(&g_tiny_class_policy_init_done, memory_order_acquire)) {
        return;
    }

    const char* profile = getenv("HAKMEM_TINY_POLICY_PROFILE");
    const char* active_profile = tiny_class_policy_set_profile(profile);

    // 1-shot ダンプでポリシーの内容を可視化（デバッグ用）
    if (atomic_exchange_explicit(&g_tiny_class_policy_logged, 1, memory_order_acq_rel) == 0) {
        fprintf(stderr, "[POLICY_INIT] profile=%s\n", active_profile);
        for (int cls = 0; cls < TINY_NUM_CLASSES; cls++) {
            TinyClassPolicy* p = &g_tiny_class_policy[cls];
            fprintf(stderr,
                    "  C%d: page=%u warm=%u cap=%u\n",
                    cls,
                    p->page_box_enabled,
                    p->warm_enabled,
                    p->warm_cap);
        }
    }

    atomic_store_explicit(&g_tiny_class_policy_init_done, 1, memory_order_release);
}