Re: The CURRENT macro

Tom Gall
2002-01-03T22:03:12Z

Michael Zhu wrote:
>
> In Alessandro Rubini's book Linux Device Driver(Second
> Edition), Chatper 12, he said that "By accessing the
> fields in the request structure, usually by way of
> CURRENT" and "CURRENT is just a pointer into
> blk_dev[MAJOR_NR].request_queue". I know CURRENT is
> just a macro. Where can I find the definition of this
> macro?
> I just don't know how to get the struct request from
> the request_queue(a request_queue_t struct). CURRENT
> points to which field in the
> blk_dev[MAJOR_NR].request_queue? Thank you very much.

Look in include/asm-[your-arch]/current.h

It's architecture dependant. For instance on PPC64 we keep current in a
register.

Regards,

Tom

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