+ mm-page_allocc-fix-obsolete-comment-in-free_pcppages_bulk.patch added to -mm tree

[akpm@linux-foundation.org]

The patch titled
     Subject: mm/page_alloc.c: fix obsolete comment in free_pcppages_bulk()
has been added to the -mm tree.  Its filename is
     mm-page_allocc-fix-obsolete-comment-in-free_pcppages_bulk.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-page_allocc-fix-obsolete-comment-in-free_pcppages_bulk.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-page_allocc-fix-obsolete-comment-in-free_pcppages_bulk.patch

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------------------------------------------------------
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The second two paragraphs about "all pages pinned" and pages_scanned is
obsolete.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
@@ -1426,14 +1426,8 @@ 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)
_

Patches currently in -mm which might be from linmiaohe@huawei.com are

mm-page_allocc-remove-meaningless-vm_bug_on-in-pindex_to_order.patch
mm-page_allocc-simplify-the-code-by-using-macro-k.patch
mm-page_allocc-fix-obsolete-comment-in-free_pcppages_bulk.patch
mm-page_allocc-use-helper-function-zone_spans_pfn.patch
mm-page_allocc-avoid-allocating-highmem-pages-via-alloc_pages_exact.patch
mm-page_isolation-fix-potential-missing-call-to-unset_migratetype_isolate.patch
mm-page_isolation-guard-against-possible-putback-unisolated-page.patch
mm-memory_hotplug-make-hwpoisoned-dirty-swapcache-pages-unmovable.patch
mm-zsmallocc-close-race-window-between-zs_pool_dec_isolated-and-zs_unregister_migration.patch
mm-zsmallocc-combine-two-atomic-ops-in-zs_pool_dec_isolated.patch