The patch titled
Subject: mm/page_alloc: update comments in __free_pages_ok()
has been added to the -mm mm-unstable branch. Its filename is
mm-page_alloc-update-comments-in-__free_pages_ok.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-page_alloc-update-comments-in-__free_pages_ok.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Deyan Wang <wonder_rock@xxxxxxx>
Subject: mm/page_alloc: update comments in __free_pages_ok()
Date: Thu, 1 Dec 2022 21:50:45 +0800
Add a comment to explain why we call get_pfnblock_migratetype() twice in
__free_pages_ok().
Link: https://lkml.kernel.org/r/20221201135045.31663-1-wonder_rock@xxxxxxx
Signed-off-by: Deyan Wang <wonder_rock@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/page_alloc.c | 5 +++++
1 file changed, 5 insertions(+)
--- a/mm/page_alloc.c~mm-page_alloc-update-comments-in-__free_pages_ok
+++ a/mm/page_alloc.c
@@ -1702,6 +1702,11 @@ static void __free_pages_ok(struct page
if (!free_pages_prepare(page, order, true, fpi_flags))
return;
+ /*
+ * Calling get_pfnblock_migratetype() without spin_lock_irqsave() here
+ * is used to avoid calling get_pfnblock_migratetype() under the lock.
+ * This will reduce the lock holding time.
+ */
migratetype = get_pfnblock_migratetype(page, pfn);
spin_lock_irqsave(&zone->lock, flags);
_
Patches currently in -mm which might be from wonder_rock@xxxxxxx are
mm-page_alloc-update-comments-in-__free_pages_ok.patch
