Re: [Lhms-devel] Re: [RFC] buddy allocator withou bitmap(2) [3/3]

[Hiroyuki KAMEZAWA <kamezawa.hiroyu@jp.fujitsu.com>]

Dave Hansen wrote:

> On Tue, 2004-08-31 at 03:47, Hiroyuki KAMEZAWA wrote:
> 
>>"Does a page's buddy page exist or not ?" is checked by following.
>>------------------------
>>if ((address of buddy is smaller than that of page) &&
>>    (page->flags & PG_buddyend))
>>    this page has no buddy in this order.
>>------------------------
> 
> 
> What about the top-of-the-zone buddyend pages?  Are those covered
> elsewhere?

If zone is not aligned to MAX_ORDER, the top-of-the-zone buddyend pages
are marked as PG_buddyend.
I forget something ?



>>+static inline int page_is_buddy(struct page *page, int order)
>>+{
>>+	if (PagePrivate(page) &&
>>+	    (page_order(page) == order) &&
>>+	    !(page->flags & (1 << PG_reserved)) &&
> 
> 
> Please use a macro.
my mistake.

> 
>> 	if (order)
>> 		destroy_compound_page(page, order);
>>+
>> 	mask = (~0UL) << order;
>> 	page_idx = page - base;
> 
> 
> Repeat after me: No whitespace changes.  No whitespace changes.  No
> whitespace changes.
> 
very sorry ;(


-- 
--the clue is these footmarks leading to the door.--
KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>

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