Remove up to two levels of indentation by using continue statements
and move variables to local scope where possible.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
mm/gup.c | 81 ++++++++++++++++++++++++++++++--------------------------
1 file changed, 44 insertions(+), 37 deletions(-)
diff --git a/mm/gup.c b/mm/gup.c
index a9d4d724aef749..37d6c24ca71225 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1868,72 +1868,79 @@ static long check_and_migrate_movable_pages(unsigned long nr_pages,
struct page **pages,
unsigned int gup_flags)
{
- unsigned long i;
- unsigned long isolation_error_count = 0;
- bool drain_allow = true;
- LIST_HEAD(movable_page_list);
- long ret = 0;
+ unsigned long isolation_error_count = 0, i;
struct page *prev_head = NULL;
- struct page *head;
- struct migration_target_control mtc = {
- .nid = NUMA_NO_NODE,
- .gfp_mask = GFP_USER | __GFP_NOWARN,
- };
+ LIST_HEAD(movable_page_list);
+ bool drain_allow = true;
+ int ret = 0;
for (i = 0; i < nr_pages; i++) {
- head = compound_head(pages[i]);
+ struct page *head = compound_head(pages[i]);
+
if (head == prev_head)
continue;
prev_head = head;
+
+ if (is_pinnable_page(head))
+ continue;
+
/*
- * If we get a movable page, since we are going to be pinning
- * these entries, try to move them out if possible.
+ * Try to move out any movable page before pinning the range.
*/
- if (!is_pinnable_page(head)) {
- if (PageHuge(head)) {
- if (!isolate_huge_page(head, &movable_page_list))
- isolation_error_count++;
- } else {
- if (!PageLRU(head) && drain_allow) {
- lru_add_drain_all();
- drain_allow = false;
- }
+ if (PageHuge(head)) {
+ if (!isolate_huge_page(head, &movable_page_list))
+ isolation_error_count++;
+ continue;
+ }
- if (isolate_lru_page(head)) {
- isolation_error_count++;
- continue;
- }
- list_add_tail(&head->lru, &movable_page_list);
- mod_node_page_state(page_pgdat(head),
- NR_ISOLATED_ANON +
- page_is_file_lru(head),
- thp_nr_pages(head));
- }
+ if (!PageLRU(head) && drain_allow) {
+ lru_add_drain_all();
+ drain_allow = false;
+ }
+
+ if (isolate_lru_page(head)) {
+ isolation_error_count++;
+ continue;
}
+ list_add_tail(&head->lru, &movable_page_list);
+ mod_node_page_state(page_pgdat(head),
+ NR_ISOLATED_ANON + page_is_file_lru(head),
+ thp_nr_pages(head));
}
+ if (!list_empty(&movable_page_list) || isolation_error_count)
+ goto unpin_pages;
+
/*
* If list is empty, and no isolation errors, means that all pages are
* in the correct zone.
*/
- if (list_empty(&movable_page_list) && !isolation_error_count)
- return nr_pages;
+ return nr_pages;
+unpin_pages:
if (gup_flags & FOLL_PIN) {
unpin_user_pages(pages, nr_pages);
} else {
for (i = 0; i < nr_pages; i++)
put_page(pages[i]);
}
+
if (!list_empty(&movable_page_list)) {
+ struct migration_target_control mtc = {
+ .nid = NUMA_NO_NODE,
+ .gfp_mask = GFP_USER | __GFP_NOWARN,
+ };
+
ret = migrate_pages(&movable_page_list, alloc_migration_target,
NULL, (unsigned long)&mtc, MIGRATE_SYNC,
MR_LONGTERM_PIN, NULL);
- if (ret && !list_empty(&movable_page_list))
- putback_movable_pages(&movable_page_list);
+ if (ret > 0) /* number of pages not migrated */
+ ret = -ENOMEM;
}
- return ret > 0 ? -ENOMEM : ret;
+ if (ret && !list_empty(&movable_page_list))
+ putback_movable_pages(&movable_page_list);
+ return ret;
}
#else
static long check_and_migrate_movable_pages(unsigned long nr_pages,
--
2.30.2
