[patch 105/262] mm/page_alloc.c: fix obsolete comment in free_pcppages_bulk()

Andrew Morton
2021-11-05T20:40:13Z

From: Miaohe Lin <linmiaohe@huawei.com>
Subject: mm/page_alloc.c: fix obsolete comment in free_pcppages_bulk()

The second two paragraphs about "all pages pinned" and pages_scanned is
obsolete. And There are PAGE_ALLOC_COSTLY_ORDER + 1 + NR_PCP_THP orders
in pcp. So the same order assumption is not held now.

Link: https://lkml.kernel.org/r/20210902121242.41607-4-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

mm/page_alloc.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)

--- a/mm/page_alloc.c~mm-page_allocc-fix-obsolete-comment-in-free_pcppages_bulk
+++ a/mm/page_alloc.c
@@ -1428,14 +1428,8 @@ static inline void prefetch_buddy(struct

/*
* Frees a number of pages from the PCP lists
- * Assumes all pages on list are in same zone, and of same order.
+ * Assumes all pages on list are in same zone.
* count is the number of pages to free.
- *
- * If the zone was previously in an "all pages pinned" state then look to
- * see if this freeing clears that state.
- *
- * And clear the zone's pages_scanned counter, to hold off the "all pages are
- * pinned" detection logic.
*/
static void free_pcppages_bulk(struct zone *zone, int count,
struct per_cpu_pages *pcp)
_