mm: hugetlbfs_pagecache_present

Rename hugetlbfs_backed() to hugetlbfs_pagecache_present()
and add more comments, as suggested by Mel Gorman.

Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Rik van Riel <riel@redhat.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Hugh Dickins 2009-09-21 17:03:33 -07:00 committed by Linus Torvalds
parent 6e919717c8
commit 3ae77f43b1
1 changed files with 11 additions and 5 deletions

View File

@ -2016,8 +2016,11 @@ static struct page *hugetlbfs_pagecache_page(struct hstate *h,
return find_lock_page(mapping, idx);
}
/* Return whether there is a pagecache page to back given address within VMA */
static bool hugetlbfs_backed(struct hstate *h,
/*
* Return whether there is a pagecache page to back given address within VMA.
* Caller follow_hugetlb_page() holds page_table_lock so we cannot lock_page.
*/
static bool hugetlbfs_pagecache_present(struct hstate *h,
struct vm_area_struct *vma, unsigned long address)
{
struct address_space *mapping;
@ -2254,10 +2257,13 @@ int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
/*
* When coredumping, it suits get_dump_page if we just return
* an error if there's a hole and no huge pagecache to back it.
* an error where there's an empty slot with no huge pagecache
* to back it. This way, we avoid allocating a hugepage, and
* the sparse dumpfile avoids allocating disk blocks, but its
* huge holes still show up with zeroes where they need to be.
*/
if (absent &&
((flags & FOLL_DUMP) && !hugetlbfs_backed(h, vma, vaddr))) {
if (absent && (flags & FOLL_DUMP) &&
!hugetlbfs_pagecache_present(h, vma, vaddr)) {
remainder = 0;
break;
}