mm: kill one if loop in __free_pages_bootmem()

We should not check loop+1 with loop end in loop body.  Just duplicate two
lines code to avoid it.

That will help a bit when we have huge amount of pages on system with
16TiB memory.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Mel Gorman <mgorman@suse.de>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Yinghai Lu 2013-09-11 14:20:37 -07:00 committed by Linus Torvalds
parent f92310c187
commit e2d0bd2b92

View file

@ -751,19 +751,19 @@ static void __free_pages_ok(struct page *page, unsigned int order)
void __init __free_pages_bootmem(struct page *page, unsigned int order) void __init __free_pages_bootmem(struct page *page, unsigned int order)
{ {
unsigned int nr_pages = 1 << order; unsigned int nr_pages = 1 << order;
struct page *p = page;
unsigned int loop; unsigned int loop;
prefetchw(page); prefetchw(p);
for (loop = 0; loop < nr_pages; loop++) { for (loop = 0; loop < (nr_pages - 1); loop++, p++) {
struct page *p = &page[loop]; prefetchw(p + 1);
if (loop + 1 < nr_pages)
prefetchw(p + 1);
__ClearPageReserved(p); __ClearPageReserved(p);
set_page_count(p, 0); set_page_count(p, 0);
} }
__ClearPageReserved(p);
set_page_count(p, 0);
page_zone(page)->managed_pages += 1 << order; page_zone(page)->managed_pages += nr_pages;
set_page_refcounted(page); set_page_refcounted(page);
__free_pages(page, order); __free_pages(page, order);
} }