Use of double pointer in linux kernel Hash list implementation

Posted by bala1486 on Stack Overflow See other posts from Stack Overflow or by bala1486
Published on 2010-06-17T02:51:21Z Indexed on 2010/06/17 3:13 UTC
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linux-kernel

Hi, I am trying to understand Linux Kernel implementation of linked list and hash table. A link to the implementation is here. I understood the linked list implementation. But i am little confused of why double pointers is being used in hlist (**pprev). Link for hlist is here. I understand that hlist is used in implementation of hash table since head of the list requires only one pointer and it saves space. Why cant it be done using single pointer (just *prev like the linked list)? Please help me.

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