mm: Convert huge_memory to XArray

Quite a straightforward conversion.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
This commit is contained in:
Matthew Wilcox 2017-12-04 10:16:10 -05:00
parent 89eb946a74
commit aa5dc07f70
1 changed files with 7 additions and 10 deletions

View File

@ -2443,13 +2443,13 @@ static void __split_huge_page(struct page *page, struct list_head *list,
ClearPageCompound(head);
/* See comment in __split_huge_page_tail() */
if (PageAnon(head)) {
/* Additional pin to radix tree of swap cache */
/* Additional pin to swap cache */
if (PageSwapCache(head))
page_ref_add(head, 2);
else
page_ref_inc(head);
} else {
/* Additional pin to radix tree */
/* Additional pin to page cache */
page_ref_add(head, 2);
xa_unlock(&head->mapping->i_pages);
}
@ -2561,7 +2561,7 @@ bool can_split_huge_page(struct page *page, int *pextra_pins)
{
int extra_pins;
/* Additional pins from radix tree */
/* Additional pins from page cache */
if (PageAnon(page))
extra_pins = PageSwapCache(page) ? HPAGE_PMD_NR : 0;
else
@ -2657,17 +2657,14 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
spin_lock_irqsave(zone_lru_lock(page_zone(head)), flags);
if (mapping) {
void **pslot;
XA_STATE(xas, &mapping->i_pages, page_index(head));
xa_lock(&mapping->i_pages);
pslot = radix_tree_lookup_slot(&mapping->i_pages,
page_index(head));
/*
* Check if the head page is present in radix tree.
* Check if the head page is present in page cache.
* We assume all tail are present too, if head is there.
*/
if (radix_tree_deref_slot_protected(pslot,
&mapping->i_pages.xa_lock) != head)
xa_lock(&mapping->i_pages);
if (xas_load(&xas) != head)
goto fail;
}