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Áù£ºkmem_cache_allocµÄʵÏÖ·ÖÎö:
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void * kmem_cache_alloc (kmem_cache_t *cachep, int flags)
{
return __cache_alloc(cachep, flags);
}
ʵ¼ÊÉÏ»áµ÷ÓÃ__cache_alloc
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static inline void * __cache_alloc (kmem_cache_t *cachep, int flags)
{
unsigned long save_flags;
void* objp;
struct array_cache *ac;
//Èç¹û¶¨ÒåÁË__GFP_WAIT¡£¿ÉÄÜ»áÒýÆð˯Ãß
cache_alloc_debugcheck_before(cachep, flags);
local_irq_save(save_flags);
//È¡µÃµ±Ç°´¦ÀíÆ÷ËùÔÚµÄarray_cache(¼ò³ÆÎªAC£¬ÎÒÃÇÏÂÃæÒ²ÕâÑù³ÆºôËü)
ac = ac_data(cachep);
//ac->avail:ACÖеںóÒ»¸ö¿ÉÓõĶÔÏóË÷Òý
//Èç¹ûACÖл¹ÓпÉÓõĶÔÏó
if (likely(ac->avail)) {
STATS_INC_ALLOCHIT(cachep);
//ÿ´Î·ÖÅä¶¼»á°Ñac->touchedÖÃΪ1
ac->touched = 1;
objp = ac_entry(ac)[--ac->avail];
} else {
//Èç¹ûACÖÐûÓпÉÓöÔÏó£¬ÄÇÖ»ÄÜ´Ól3ÖГ°á³ö”¶ÔÏóµ½ACÖÐ
STATS_INC_ALLOCMISS(cachep);
objp = cache_alloc_refill(cachep, flags);
}
local_irq_restore(save_flags);
objp = cache_alloc_debugcheck_after(cachep, flags, objp, __builtin_return_address(0));
return objp;
}
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for i in `find . -type f -name "*.c"`
do
echo $i
basename $i »ñÈ¡*.cÎļþÃû
dirname $i »ñÈ¡*.c¶ÔÓ¦µÄĿ¼Ãû
done
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bin = BINaries
/dev = DEVices
/etc = ETCetera
/lib = LIBrary
/proc = PROCesses
/sbin = Superuser BINaries
/tmp = TeMPorary
/usr = Unix Shared Resources
/var = VARiable ?
FIFO = First In, First Out
GRUB = GRand Unified Bootloader
IFS = Internal Field Seperators
LILO ......