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1. ǰÑÔ
kmem_cacheÊÇLinuxÄÚºËÌṩµÄ¿ìËÙÄڴ滺³å½Ó¿Ú£¬ÕâЩÄÚ´æ¿éÒªÇóÊÇ´óСÏàͬµÄ£¬ÒòΪ·ÖÅä³öµÄÄÚ
´æÔÚ½Ó¿ÚÊÍ·Åʱ²¢²»ÕæÕýÊÍ·Å£¬¶øÊÇ×÷Ϊ»º´æ±£Áô£¬ÏÂÒ»´ÎÇëÇó·ÖÅäʱ¾Í¿ÉÒÔÖ±½ÓʹÓã¬Ê¡È¥Á˸÷ÖÖ
ÄÚ´æ¿é³õʼ»¯»òÊͷŵIJÙ×÷£¬Òò´Ë·ÖÅäËٶȺܿ죬ͨ³£ÓÃÓÚ´óÊýÁ¿µÄÄÚ´æ¿é·ÖÅäµÄÇé¿ö£¬Èçinode½Ú
µã£¬skbuffÍ·, netfilterµÄÁ¬½ÓµÈ£¬ÆäʵkmallocÒ²ÊÇ´Ókmem_cacheÖзÖÅäµÄ£¬¿Éͨ
¹ý/proc/slabinfoÎļþÖ±½Ó¶ÁÈ¡cache·ÖÅäÇé¿ö¡£
ÒÔÏÂLinuxÄں˴úÂë°æ±¾Îª2.6.19.2, ³ÌÐòÖ÷Òª³ö×Ômm/slab.cÎļþ, 2.4ºÍ2.6»ù±¾Ô­Àí²î²»¶à,µ«¾ß
ÌåʵÏÖÖÐÓÐÁ˲»Éٱ仯¡£
2. slabºÍpage
ÔÚ½éÉÜkmem_cache֮ǰÐèÒªÏȽéÉÜpageºÍslabÕâÁ½¸ö¶¨Òå¡£ÖÚËùÖÜÖª£¬pageÊÇÄÚºËÖÐÄÚ´æ»ù±¾¹ÜÀíµ¥
λ£¬Ã¿¸öpageµÄÄÚ´æ´óСÊǹ̶¨µÄ£¬¶ÔX86»úÆ÷À´Ëµ£¬ÊÇ4K£»slabÔòÊÇkmem_cacheµÄ¾ßÌåµÄÄÚ´æ¿Õ¼ä
ÐÎʽ£¬¸ù¾ÝcacheµÄ¶ÔÏóµÄ´óС£¬Ã¿¸öslab¿ÉÒÔÓÐ1¸öpageµ½×î¶à32(128/4)¸öpage£»Èç¹ûcache¶ÔÏó±È
Ò»¸öpageµÄ¿Õ¼äС£¬Õâ¸öslabÖлáÈÝÄɶà¸ö¶ÔÏóÒÔ¾¡¿ÉÄܵØÀûÓÿռ䡣
struct slab {
// Á´±í
 struct list_head list;
// δÓÿռäµÄÆ«ÒÆ
 unsigned long colouroff;
// ¾ßÌåµÄÄڴ滺³åÇøµØÖ·
 void *s_mem;  /* including colour offset */
// ÿ¸öslabÖеÄÕýÔÚʹÓõĶÔÏóÊýÁ¿
 unsigned int inuse; /* num of objs active in slab */
// ¿ÕÏжÔÏó
 kmem_bufctl_t free;
 unsigned short nodeid;
};
 
3. Êý¾Ý½á¹¹
kmem_cacheÊý¾Ý½á¹¹²¢Ã»Óж¨ÒåÔÚ.hµÄÍ·ÎļþÖУ¬ÔÚÍ·ÎļþÖÐÖ»ÊǸýṹµÄÒ»¸öÀàÐͶ¨Ò壬ÒòΪÆäËû
µØ·½Ê¹ÓÃkmem_cacheʱÍêÈ«²»ÐèÒªÖªµÀÆäÄÚ²¿½á¹¹£¬¸÷½Ó¿Úº¯ÊýÍêÈ«·â×°½á¹¹ÖеÄÐÅÏ¢£¬ÕâÊÇÓÃCʵ
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/* include/linux/slab.h */
// ÕâÀïÖ»ÊÇÒ»¸öÀàÐͶ¨Òå
typedef struct kmem_cache kmem_cache_t;
/* mm/slab.c */
// ÔÚCÎļþÖнøÐÐÍêÕûµÄ¶¨Òå
/*
 * struct array_cache
 *
 * Purpose:
 * - LIFO ordering, to hand out cache-warm objects from _alloc
 * - reduce the number of linked list operations
 * - reduce spinlock operations
 *
 * The limit is stored in the per-cpu structure to reduce the data cache
 * footprint.
 *
 */
// ÕâÊÇÿ¸öCPU¶ÔÓ¦µÄcacheÊý¾Ý
struct array_cache {
 unsign


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