iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

migrate_pages(): remove unnecessary list_safe_reset_next()

Browse Source 
Before commit b5bade978e9b ("mm: migrate: fix the return value of
migrate_pages()"), the tail pages of THP will be put in the "from"
list directly.  So one of the loop cursors (page2) needs to be reset,
as is done in try_split_thp() via list_safe_reset_next().  But after
the commit, the tail pages of THP will be put in a dedicated
list (thp_split_pages).  That is, the "from" list will not be changed
during splitting.  So, it's unnecessary to call list_safe_reset_next()
anymore.

This is a code cleanup, no functionality changes are expected.

Link: https://lkml.kernel.org/r/20220817081408.513338-3-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Huang Ying 2022-08-17 16:14:02 +08:00 committed by Andrew Morton
parent a7504ed14f
commit 9c62ff005f
1 changed files with 5 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
mm/migrate.c
View File

@ -1369,16 +1369,13 @@ out:
return rc;
}
static inline int try_split_thp(struct page *page, struct page **page2,
struct list_head *from)
static inline int try_split_thp(struct page *page, struct list_head *split_pages)
{
int rc = 0;
int rc;
lock_page(page);
rc = split_huge_page_to_list(page, from);
rc = split_huge_page_to_list(page, split_pages);
unlock_page(page);
if (!rc)
list_safe_reset_next(page, *page2, lru);
return rc;
}
@ -1482,7 +1479,7 @@ retry:
/* THP migration is unsupported */
if (is_thp) {
nr_thp_failed++;
if (!try_split_thp(page, &page2, &thp_split_pages)) {
if (!try_split_thp(page, &thp_split_pages)) {
nr_thp_split++;
goto retry;
}
@ -1501,7 +1498,7 @@ retry:
*/
if (is_thp && !nosplit) {
nr_thp_failed++;
if (!try_split_thp(page, &page2, &thp_split_pages)) {
if (!try_split_thp(page, &thp_split_pages)) {
nr_thp_split++;
goto retry;
}