hakmem/core/box/tiny_class_stats_box.c

// tiny_class_stats_box.c - Thread-local stats storage for Tiny classes

#include "tiny_class_stats_box.h"
#include "tiny_mem_stats_box.h"
#include <stdio.h>
#include <string.h>

__thread TinyClassStatsThread g_tiny_class_stats = {0};
_Atomic uint64_t g_tiny_class_stats_uc_miss_global[TINY_NUM_CLASSES] = {0};
_Atomic uint64_t g_tiny_class_stats_warm_hit_global[TINY_NUM_CLASSES] = {0};
_Atomic uint64_t g_tiny_class_stats_shared_lock_global[TINY_NUM_CLASSES] = {0};
_Atomic uint64_t g_tiny_class_stats_tls_carve_attempt_global[TINY_NUM_CLASSES] = {0};
_Atomic uint64_t g_tiny_class_stats_tls_carve_success_global[TINY_NUM_CLASSES] = {0};
static _Atomic int g_tiny_class_stats_mem_recorded = 0;

static void tiny_class_stats_record_mem_once(void) {
    if (atomic_exchange_explicit(&g_tiny_class_stats_mem_recorded, 1, memory_order_acq_rel) == 0) {
        tiny_mem_stats_add_policy_stats((ssize_t)sizeof(g_tiny_class_stats));
        tiny_mem_stats_add_policy_stats((ssize_t)sizeof(g_tiny_class_stats_uc_miss_global));
        tiny_mem_stats_add_policy_stats((ssize_t)sizeof(g_tiny_class_stats_warm_hit_global));
        tiny_mem_stats_add_policy_stats((ssize_t)sizeof(g_tiny_class_stats_shared_lock_global));
        tiny_mem_stats_add_policy_stats((ssize_t)sizeof(g_tiny_class_stats_tls_carve_attempt_global));
        tiny_mem_stats_add_policy_stats((ssize_t)sizeof(g_tiny_class_stats_tls_carve_success_global));
    }
}

void tiny_class_stats_reset_thread(void) {
    memset(&g_tiny_class_stats, 0, sizeof(g_tiny_class_stats));
}

void tiny_class_stats_snapshot_thread(TinyClassStatsThread* out) {
    if (!out) return;
    tiny_class_stats_record_mem_once();
    memcpy(out, &g_tiny_class_stats, sizeof(*out));
}

void tiny_class_stats_snapshot_global(TinyClassStatsThread* out) {
    if (!out) return;
    tiny_class_stats_record_mem_once();
    for (int i = 0; i < TINY_NUM_CLASSES; i++) {
        out->uc_miss[i] = atomic_load_explicit(&g_tiny_class_stats_uc_miss_global[i],
                                               memory_order_relaxed);
        out->warm_hit[i] = atomic_load_explicit(&g_tiny_class_stats_warm_hit_global[i],
                                                memory_order_relaxed);
        out->shared_lock[i] = atomic_load_explicit(&g_tiny_class_stats_shared_lock_global[i],
                                                   memory_order_relaxed);
        out->tls_carve_attempt[i] = atomic_load_explicit(
            &g_tiny_class_stats_tls_carve_attempt_global[i], memory_order_relaxed);
        out->tls_carve_success[i] = atomic_load_explicit(
            &g_tiny_class_stats_tls_carve_success_global[i], memory_order_relaxed);
    }
}

static void tiny_class_stats_dump_common(FILE* out,
                                         const char* tag,
                                         const TinyClassStatsThread* stats) {
    if (!(out && stats)) return;
    fprintf(out, "%s class uc_miss warm_hit shared_lock tls_carve_attempt tls_carve_success\n",
            tag ? tag : "[STATS]");
    for (int c = 0; c < TINY_NUM_CLASSES; c++) {
        if (stats->uc_miss[c] || stats->warm_hit[c] || stats->shared_lock[c] ||
            stats->tls_carve_attempt[c] || stats->tls_carve_success[c]) {
            fprintf(out, "  C%d: %llu %llu %llu %llu %llu\n",
                    c,
                    (unsigned long long)stats->uc_miss[c],
                    (unsigned long long)stats->warm_hit[c],
                    (unsigned long long)stats->shared_lock[c],
                    (unsigned long long)stats->tls_carve_attempt[c],
                    (unsigned long long)stats->tls_carve_success[c]);
        }
    }
}

void tiny_class_stats_dump_thread(FILE* out, const char* tag) {
    TinyClassStatsThread snap = {0};
    tiny_class_stats_snapshot_thread(&snap);
    tiny_class_stats_dump_common(out, tag ? tag : "[THREAD_STATS]", &snap);
}

void tiny_class_stats_dump_global(FILE* out, const char* tag) {
    TinyClassStatsThread snap = {0};
    tiny_class_stats_snapshot_global(&snap);
    tiny_class_stats_dump_common(out, tag ? tag : "[GLOBAL_STATS]", &snap);
}