slab：编译器辅助的类型化 slab 缓存分区 — 按类型隔离对象减少内存碎片与跨对象污染

+#ifdef CONFIG_KMALLOC_PARTITION_CACHES
+typedef struct { unsigned long v; } kmalloc_token_t;
+#ifdef CONFIG_KMALLOC_PARTITION_RANDOM
+extern unsigned long random_kmalloc_seed;
+#define __kmalloc_token(...) ((kmalloc_token_t){ .v = _RET_IP_ })
+#elif defined(CONFIG_KMALLOC_PARTITION_TYPED)
+#define __kmalloc_token(...) ((kmalloc_token_t){ .v = __builtin_infer_alloc_token(__VA_ARGS__) })
+#endif
...
-extern unsigned long random_kmalloc_seed;
-
-static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags, unsigned long caller)
+static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags, kmalloc_token_t token)
 {
 	/*
 	 * The most common case is KMALLOC_NORMAL, so test for it
 	 * with a single branch for all the relevant flags.
 	 */
 	if (likely((flags & KMALLOC_NOT_NORMAL_BITS) == 0))
-#ifdef CONFIG_RANDOM_KMALLOC_CACHES
-		/* RANDOM_KMALLOC_CACHES_NR (=15) copies + the KMALLOC_NORMAL */
-		return KMALLOC_RANDOM_START + hash_64(caller ^ random_kmalloc_seed,
-						      ilog2(RANDOM_KMALLOC_CACHES_NR + 1));
+#ifdef CONFIG_KMALLOC_PARTITION_RANDOM
+		/* KMALLOC_PARTITION_CACHES_NR (=15) copies + the KMALLOC_NORMAL */
+		return KMALLOC_PARTITION_START + hash_64(token.v ^ random_kmalloc_seed,
+							 ilog2(KMALLOC_PARTITION_CACHES_NR + 1));
+#elif defined(CONFIG_KMALLOC_PARTITION_TYPED)
+		return KMALLOC_PARTITION_START + token.v;
 #else
 		return KMALLOC_NORMAL;
 #endif