ppclinux and idle task zero-ing pages

Cort (cort@cs.nmt.edu)
Wed, 26 Mar 1997 00:43:25 -0700

I've written the idle task of ppclinux to zero out pages and keep them in a
linked list -- zero_list. I put a check for pre-zero'd pages in
get_free_pages() that will return one of these pre-zero'd pages and get a
page the normal way and clear it if there's not one available.

As it is now, I'm using __get_free_pages() to get a page to work with since
that'll take it out of the free list. Once the page is zero'd I add it to
zero_list.

I'd like to add a bit to the freelist to mark a page as zero'd instead
since the page is technically 'free' but then I'll also need a busy bit
when I'm zero'ing a page or at least a way to detect when the page has been
given away without checking the freelist everytime I get an interrupt or
reschedule in the idle task.

Does anyone have some suggestions or ideas on where to put this?