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º¯ÊývmallocÁгöÈçÏÂ:(mm/vmalloc.c)
size: ·ÖÅäµÄÐéÄâ¿Õ¼äµÄ´óС.
gfp_mask: Ò³¼¶·ÖÅäÆ÷µÄ±êÖ¾.
prot: ÒÑ·ÖÅäµÄ±£»¤ÑÚÂë.
void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot)
{
return __vmalloc_node(size, gfp_mask, prot, -1,
__builtin_return_address(0));
}
º¯Êý_vmalloc·ÖÅä×ã¹»µÄÒ³ÊýÓësizeÏàÅä,°ÑËüÃÇÓ³Éä½øÁ¬ÐøµÄÄÚºËÐéÄâ¿Õ¼ä,µ«·ÖÅäµÄÄÚ´æ¿é²»Ò»¶¨Á¬Ðø.ÔÚº¯ÊýÖеÚÒ»²½ÊÇÔÚvmlistÖÐÑ°ÕÒµ½Ò»¸ö´óСºÏÊʵÄÐéÄâÄÚ´æ¿é(_get_vm_area_node(...)).
static void *__vmalloc_node(unsigned long size, gfp_t gfp_mask, pgprot_t prot,
int node, void *caller)
{
struct vm_struct *area;
//¼ì²éÇëÇó·ÖÅäµÄÄÚ´æ´óСÓÐûÓг¬¹ý×î´óµÄÎïÀíÒ³ÃæÊý¡£Èç¹û³¬¹ý·µ»Ø 0 £¬±íʾ·ÖÅäʧ°Ü¡£
size = PAGE_ALIGN(size);
//ÓÐЧÐÔ¼ì²é
if (!size || (size >> PAGE_SHIFT) > num_physpages)
return NULL;
//È¡µÃÒ»¸öÓÐЧµÄvma
area = __get_vm_area_node(size, VM_ALLOC, VMALLOC_START, VMALLOC_END,
node, gfp_mask, caller);
//Èç¹ûÉêÇëµÄÎÞЧ£¬·µ»ØÒ»¸öNULLÖ¸Õë
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main.c
//³õʼ»¯¶ÓÁÐ
void InitQueue(LiQueue *q)
{
q=(LiQueue*)malloc(sizeof(LiQueue));
q->front=q->rear=NULL;
}
//ÅжÏÊÇ·ñΪ¿Õ
int QueueEmpty(LiQueue *q)
{
if(q->rear==NULL)
{
return 1;
}
else
{
......
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