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core/superslab_stats.c

@@ -4,6 +4,7 @@
 // Date: 2025-11-28
 
 #include "hakmem_tiny_superslab_internal.h"
+#include <stdlib.h>
 
 // ============================================================================
 // Global Statistics
@@ -30,6 +31,11 @@ uint64_t g_ss_freed_by_class[8] = {0};
 _Atomic uint64_t g_ss_mmap_count = 0;
 _Atomic uint64_t g_final_fallback_mmap_count = 0;
 
+// Superslab/slab observability (Tiny-only; relaxed updates)
+_Atomic uint64_t g_ss_live_by_class[8]   = {0};
+_Atomic uint64_t g_ss_empty_events[8]    = {0};
+_Atomic uint64_t g_slab_live_events[8]   = {0};
+
 // ============================================================================
 // Statistics Functions
 // ============================================================================
@@ -56,6 +62,35 @@ void ss_stats_cache_store(void) {
     pthread_mutex_unlock(&g_superslab_lock);
 }
 
+void ss_stats_on_ss_alloc_class(int class_idx) {
+    if (class_idx >= 0 && class_idx < 8) {
+        atomic_fetch_add_explicit(&g_ss_live_by_class[class_idx], 1, memory_order_relaxed);
+    }
+}
+
+void ss_stats_on_ss_free_class(int class_idx) {
+    if (class_idx >= 0 && class_idx < 8) {
+        uint64_t prev = atomic_load_explicit(&g_ss_live_by_class[class_idx], memory_order_relaxed);
+        if (prev > 0) {
+            atomic_fetch_sub_explicit(&g_ss_live_by_class[class_idx], 1, memory_order_relaxed);
+        }
+    }
+}
+
+void ss_stats_on_ss_scan(int class_idx, int slab_live, int is_empty) {
+    if (class_idx < 0 || class_idx >= 8) {
+        return;
+    }
+    if (slab_live > 0) {
+        atomic_fetch_add_explicit(&g_slab_live_events[class_idx],
+                                  (uint64_t)slab_live,
+                                  memory_order_relaxed);
+    }
+    if (is_empty) {
+        atomic_fetch_add_explicit(&g_ss_empty_events[class_idx], 1, memory_order_relaxed);
+    }
+}
+
 // ============================================================================
 // Diagnostics
 // ============================================================================
@@ -164,3 +199,23 @@ void superslab_print_global_stats(void) {
     printf("Total bytes allocated: %lu MB\n", g_bytes_allocated / (1024 * 1024));
     pthread_mutex_unlock(&g_superslab_lock);
 }
+
+void ss_stats_dump_if_requested(void) {
+    const char* env = getenv("HAKMEM_SS_STATS_DUMP");
+    if (!env || !*env || *env == '0') {
+        return;
+    }
+    fprintf(stderr, "[SS_STATS] class live empty_events slab_live_events\n");
+    for (int c = 0; c < 8; c++) {
+        uint64_t live = atomic_load_explicit(&g_ss_live_by_class[c], memory_order_relaxed);
+        uint64_t empty = atomic_load_explicit(&g_ss_empty_events[c], memory_order_relaxed);
+        uint64_t slab_live = atomic_load_explicit(&g_slab_live_events[c], memory_order_relaxed);
+        if (live || empty || slab_live) {
+            fprintf(stderr, "  C%d: live=%llu empty=%llu slab_live=%llu\n",
+                    c,
+                    (unsigned long long)live,
+                    (unsigned long long)empty,
+                    (unsigned long long)slab_live);
+        }
+    }
+}