+ mm-swap-remove-swap_flag_prio_shift.patch added to mm-unstable branch

+ mm-swap-remove-swap_flag_prio_shift.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/swap: remove SWAP_FLAG_PRIO_SHIFT
has been added to the -mm mm-unstable branch.  Its filename is
     mm-swap-remove-swap_flag_prio_shift.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-swap-remove-swap_flag_prio_shift.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: Baoquan He <bhe@redhat.com>
Subject: mm/swap: remove SWAP_FLAG_PRIO_SHIFT
Date: Wed, 5 Feb 2025 17:27:12 +0800

It doesn't make sense to have a zero value of shift.  Remove it to avoid
confusion.

Link: https://lkml.kernel.org/r/20250205092721.9395-4-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Chis Li <chrisl@kernel.org>
Cc: Kairui Song <ryncsn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/swap.h |    1 -
 mm/swapfile.c        |    3 +--
 2 files changed, 1 insertion(+), 3 deletions(-)

--- a/include/linux/swap.h~mm-swap-remove-swap_flag_prio_shift
+++ a/include/linux/swap.h
@@ -24,7 +24,6 @@ struct pagevec;
 
 #define SWAP_FLAG_PREFER	0x8000	/* set if swap priority specified */
 #define SWAP_FLAG_PRIO_MASK	0x7fff
-#define SWAP_FLAG_PRIO_SHIFT	0
 #define SWAP_FLAG_DISCARD	0x10000 /* enable discard for swap */
 #define SWAP_FLAG_DISCARD_ONCE	0x20000 /* discard swap area at swapon-time */
 #define SWAP_FLAG_DISCARD_PAGES 0x40000 /* discard page-clusters after use */
--- a/mm/swapfile.c~mm-swap-remove-swap_flag_prio_shift
+++ a/mm/swapfile.c
@@ -3449,8 +3449,7 @@ SYSCALL_DEFINE2(swapon, const char __use
 	mutex_lock(&swapon_mutex);
 	prio = -1;
 	if (swap_flags & SWAP_FLAG_PREFER)
-		prio =
-		  (swap_flags & SWAP_FLAG_PRIO_MASK) >> SWAP_FLAG_PRIO_SHIFT;
+		prio = swap_flags & SWAP_FLAG_PRIO_MASK;
 	enable_swap_info(si, prio, swap_map, cluster_info, zeromap);
 
 	pr_info("Adding %uk swap on %s.  Priority:%d extents:%d across:%lluk %s%s%s%s\n",
_

Patches currently in -mm which might be from bhe@redhat.com are

mm-swap_statec-fix-the-obsolete-code-comment.patch
mm-swap_statec-optimize-the-code-in-clear_shadow_from_swap_cache.patch
mm-swap-remove-swap_flag_prio_shift.patch
mm-swap-skip-scanning-cluster-range-if-its-empty-cluster.patch
mm-swap-rename-swap_is_has_cache-to-swap_only_has_cache.patch
mm-swapfilec-update-the-code-comment-above-swap_count_continued.patch
mm-swapfilec-optimize-code-in-setup_clusters.patch
mm-swap_statec-remove-the-meaningless-code-comment.patch
mm-swapfilec-remove-the-unneeded-checking.patch
mm-swap-rename-swap_swapcount-to-swap_entry_swapped.patch
mm-swapfilec-remove-the-incorrect-code-comment.patch
mm-swapfilec-open-code-cluster_alloc_swap.patch