+ mm-memcg-minor-cleanup-for-mc_handle_present_pte.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm/memcg: minor cleanup for mc_handle_present_pte()
has been added to the -mm mm-unstable branch.  Its filename is
     mm-memcg-minor-cleanup-for-mc_handle_present_pte.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memcg-minor-cleanup-for-mc_handle_present_pte.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: Miaohe Lin <linmiaohe@huawei.com>
Subject: mm/memcg: minor cleanup for mc_handle_present_pte()
Date: Mon, 17 Jul 2023 19:36:44 +0800

When pagetable lock is held, the page will always be page_mapped().  So
remove unneeded page_mapped() check.  Also the page can't be freed from
under us in this case.  So use get_page() to get extra page reference to
simplify the code.  No functional change intended.

Link: https://lkml.kernel.org/r/20230717113644.3026478-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memcontrol.c |    5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

--- a/mm/memcontrol.c~mm-memcg-minor-cleanup-for-mc_handle_present_pte
+++ a/mm/memcontrol.c
@@ -5639,7 +5639,7 @@ static struct page *mc_handle_present_pt
 {
 	struct page *page = vm_normal_page(vma, addr, ptent);
 
-	if (!page || !page_mapped(page))
+	if (!page)
 		return NULL;
 	if (PageAnon(page)) {
 		if (!(mc.flags & MOVE_ANON))
@@ -5648,8 +5648,7 @@ static struct page *mc_handle_present_pt
 		if (!(mc.flags & MOVE_FILE))
 			return NULL;
 	}
-	if (!get_page_unless_zero(page))
-		return NULL;
+	get_page(page);
 
 	return page;
 }
_

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

mm-mm_initc-update-obsolete-comment-in-get_pfn_range_for_nid.patch
mm-memory-failure-fix-unexpected-return-value-in-soft_offline_page.patch
mm-memory-failure-fix-potential-page-refcnt-leak-in-memory_failure.patch
mm-memory-failure-remove-unneeded-page-state-check-in-shake_page.patch
memory-tier-use-helper-function-destroy_memory_type.patch
mm-memory-failure-remove-unneeded-inline-annotation.patch
mm-mm_initc-remove-obsolete-macro-hash_small.patch
mm-page_alloc-avoid-false-page-outside-zone-error-info.patch
memory-tier-rename-destroy_memory_type-to-put_memory_type.patch
mm-remove-obsolete-comment-above-struct-per_cpu_pages.patch
mm-memcg-minor-cleanup-for-mem_cgroup_id_max.patch
mm-memory-failure-remove-unneeded-pagehuge-check.patch
mm-memory-failure-ensure-moving-hwpoison-flag-to-the-raw-error-pages.patch
mm-memory-failure-dont-account-hwpoison_filter-filtered-pages.patch
mm-memory-failure-use-local-variable-huge-to-check-hugetlb-page.patch
mm-memory-failure-remove-unneeded-header-files.patch
mm-memory-failure-minor-cleanup-for-comments-and-codestyle.patch
mm-memory-failure-fetch-compound-head-after-extra-page-refcnt-is-held.patch
mm-memory-failure-fix-race-window-when-trying-to-get-hugetlb-folio.patch
mm-huge_memory-use-rmap_none-when-calling-page_add_anon_rmap.patch
mm-memcg-fix-obsolete-comment-above-mem_cgroup_max_reclaim_loops.patch
mm-memcg-minor-cleanup-for-mc_handle_present_pte.patch