hakmem/core/box/tiny_policy_learner_box.c

// tiny_policy_learner_box.c - Placeholder learner hook

#include "tiny_policy_learner_box.h"
#include "tiny_class_policy_box.h"
#include "tiny_class_stats_box.h"
#include <stdint.h>

// Simple OBSERVE/LEARN rule:
//   - Choose top-2 classes by shared_pool_lock and enable Page Box for them.
//   - Always keep existing warm_enabled / warm_cap (policy table is already seeded).
void tiny_policy_learner_tick(void) {
    TinyClassStatsThread snap = {0};
    tiny_class_stats_snapshot_global(&snap);

    int top1 = -1, top2 = -1;
    uint64_t v1 = 0, v2 = 0;
    for (int i = 0; i < TINY_NUM_CLASSES; i++) {
        uint64_t v = snap.shared_lock[i];
        if (v > v1) {
            top2 = top1;
            v2 = v1;
            top1 = i;
            v1 = v;
        } else if (v > v2) {
            top2 = i;
            v2 = v;
        }
    }

    // Nothing observed yet → leave policy untouched
    if (v1 == 0) {
        return;
    }

    for (int c = 0; c < TINY_NUM_CLASSES; c++) {
        TinyClassPolicy* p = &g_tiny_class_policy[c];
        if (c == top1 || c == top2) {
            p->page_box_enabled = 1;
            p->warm_enabled = 1;
        }
    }
}