+ mm-swap-fold-swap_info_get_cont-in-the-only-caller.patch added to mm-unstable branch

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

The patch titled
     Subject: mm, swap: fold swap_info_get_cont in the only caller
has been added to the -mm mm-unstable branch.  Its filename is
     mm-swap-fold-swap_info_get_cont-in-the-only-caller.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-swap-fold-swap_info_get_cont-in-the-only-caller.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: Kairui Song <kasong@tencent.com>
Subject: mm, swap: fold swap_info_get_cont in the only caller
Date: Tue, 31 Dec 2024 01:46:10 +0800

The name of the function is confusing, and the code is much easier to
follow after folding, also rename the confusing naming "p" to more
meaningful "si".

Link: https://lkml.kernel.org/r/20241230174621.61185-3-ryncsn@gmail.com
Signed-off-by: Kairui Song <kasong@tencent.com>
Cc: Barry Song <v-songbaohua@oppo.com>
Cc: Chris Li <chrisl@kernel.org>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/swapfile.c |   39 +++++++++++++++------------------------
 1 file changed, 15 insertions(+), 24 deletions(-)

--- a/mm/swapfile.c~mm-swap-fold-swap_info_get_cont-in-the-only-caller
+++ a/mm/swapfile.c
@@ -1375,22 +1375,6 @@ out:
 	return NULL;
 }
 
-static struct swap_info_struct *swap_info_get_cont(swp_entry_t entry,
-					struct swap_info_struct *q)
-{
-	struct swap_info_struct *p;
-
-	p = _swap_info_get(entry);
-
-	if (p != q) {
-		if (q != NULL)
-			spin_unlock(&q->lock);
-		if (p != NULL)
-			spin_lock(&p->lock);
-	}
-	return p;
-}
-
 static unsigned char __swap_entry_free_locked(struct swap_info_struct *si,
 					      unsigned long offset,
 					      unsigned char usage)
@@ -1687,14 +1671,14 @@ static int swp_entry_cmp(const void *ent
 
 void swapcache_free_entries(swp_entry_t *entries, int n)
 {
-	struct swap_info_struct *p, *prev;
+	struct swap_info_struct *si, *prev;
 	int i;
 
 	if (n <= 0)
 		return;
 
 	prev = NULL;
-	p = NULL;
+	si = NULL;
 
 	/*
 	 * Sort swap entries by swap device, so each lock is only taken once.
@@ -1704,13 +1688,20 @@ void swapcache_free_entries(swp_entry_t
 	if (nr_swapfiles > 1)
 		sort(entries, n, sizeof(entries[0]), swp_entry_cmp, NULL);
 	for (i = 0; i < n; ++i) {
-		p = swap_info_get_cont(entries[i], prev);
-		if (p)
-			swap_entry_range_free(p, entries[i], 1);
-		prev = p;
+		si = _swap_info_get(entries[i]);
+
+		if (si != prev) {
+			if (prev != NULL)
+				spin_unlock(&prev->lock);
+			if (si != NULL)
+				spin_lock(&si->lock);
+		}
+		if (si)
+			swap_entry_range_free(si, entries[i], 1);
+		prev = si;
 	}
-	if (p)
-		spin_unlock(&p->lock);
+	if (si)
+		spin_unlock(&si->lock);
 }
 
 int __swap_count(swp_entry_t entry)
_

Patches currently in -mm which might be from kasong@tencent.com are

mm-list_lru-fix-false-warning-of-negative-counter.patch
mm-madvise-fix-potential-workingset-node-list_lru-leaks.patch
mm-memcontrol-avoid-duplicated-memcg-enable-check.patch
mm-swap_cgroup-remove-swap_cgroup_cmpxchg.patch
mm-swap_cgroup-remove-global-swap-cgroup-lock.patch
mm-swap_cgroup-decouple-swap-cgroup-recording-and-clearing.patch
mm-swap-minor-clean-up-for-swap-entry-allocation.patch
mm-swap-fold-swap_info_get_cont-in-the-only-caller.patch
mm-swap-remove-old-allocation-path-for-hdd.patch
mm-swap-use-cluster-lock-for-hdd.patch
mm-swap-clean-up-device-availability-check.patch
mm-swap-clean-up-plist-removal-and-adding.patch
mm-swap-hold-a-reference-during-scan-and-cleanup-flag-usage.patch
mm-swap-use-an-enum-to-define-all-cluster-flags-and-wrap-flags-changes.patch
mm-swap-reduce-contention-on-device-lock.patch
mm-swap-simplify-percpu-cluster-updating.patch
mm-swap-introduce-a-helper-for-retrieving-cluster-from-offset.patch
mm-swap-use-a-global-swap-cluster-for-non-rotation-devices.patch
mm-swap_slots-remove-slot-cache-for-freeing-path.patch