[merged mm-stable] mm-swap-add-helper-swap_offset_available.patch removed from -mm tree

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

The quilt patch titled
     Subject: mm/swap: add helper swap_offset_available()
has been removed from the -mm tree.  Its filename was
     mm-swap-add-helper-swap_offset_available.patch

This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: Miaohe Lin <linmiaohe@huawei.com>
Subject: mm/swap: add helper swap_offset_available()

Add helper swap_offset_available() to remove some duplicated codes.  Minor
readability improvement.

[akpm@linux-foundation.org: s/swap_offset_available/swap_offset_available_and_locked/, per Neil]
Link: https://lkml.kernel.org/r/20220509131416.17553-12-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/swapfile.c |   34 ++++++++++++++++++----------------
 1 file changed, 18 insertions(+), 16 deletions(-)

--- a/mm/swapfile.c~mm-swap-add-helper-swap_offset_available
+++ a/mm/swapfile.c
@@ -775,6 +775,22 @@ static void set_cluster_next(struct swap
 	this_cpu_write(*si->cluster_next_cpu, next);
 }
 
+static bool swap_offset_available_and_locked(struct swap_info_struct *si,
+					     unsigned long offset)
+{
+	if (data_race(!si->swap_map[offset])) {
+		spin_lock(&si->lock);
+		return true;
+	}
+
+	if (vm_swap_full() && READ_ONCE(si->swap_map[offset]) == SWAP_HAS_CACHE) {
+		spin_lock(&si->lock);
+		return true;
+	}
+
+	return false;
+}
+
 static int scan_swap_map_slots(struct swap_info_struct *si,
 			       unsigned char usage, int nr,
 			       swp_entry_t slots[])
@@ -952,15 +968,8 @@ done:
 scan:
 	spin_unlock(&si->lock);
 	while (++offset <= READ_ONCE(si->highest_bit)) {
-		if (data_race(!si->swap_map[offset])) {
-			spin_lock(&si->lock);
-			goto checks;
-		}
-		if (vm_swap_full() &&
-		    READ_ONCE(si->swap_map[offset]) == SWAP_HAS_CACHE) {
-			spin_lock(&si->lock);
+		if (swap_offset_available_and_locked(si, offset))
 			goto checks;
-		}
 		if (unlikely(--latency_ration < 0)) {
 			cond_resched();
 			latency_ration = LATENCY_LIMIT;
@@ -969,15 +978,8 @@ scan:
 	}
 	offset = si->lowest_bit;
 	while (offset < scan_base) {
-		if (data_race(!si->swap_map[offset])) {
-			spin_lock(&si->lock);
+		if (swap_offset_available_and_locked(si, offset))
 			goto checks;
-		}
-		if (vm_swap_full() &&
-		    READ_ONCE(si->swap_map[offset]) == SWAP_HAS_CACHE) {
-			spin_lock(&si->lock);
-			goto checks;
-		}
 		if (unlikely(--latency_ration < 0)) {
 			cond_resched();
 			latency_ration = LATENCY_LIMIT;
_

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

mm-z3fold-fix-sheduling-while-atomic.patch
mm-z3fold-fix-possible-null-pointer-dereferencing.patch
mm-z3fold-remove-buggy-use-of-stale-list-for-allocation.patch
mm-z3fold-throw-warning-on-failure-of-trylock_page-in-z3fold_alloc.patch
revert-mm-z3foldc-allow-__gfp_highmem-in-z3fold_alloc.patch
mm-z3fold-put-z3fold-page-back-into-unbuddied-list-when-reclaim-or-migration-fails.patch
mm-z3fold-always-clear-page_claimed-under-z3fold-page-lock.patch
mm-z3fold-fix-z3fold_reclaim_page-races-with-z3fold_free.patch
mm-z3fold-fix-z3fold_page_migrate-races-with-z3fold_map.patch
mm-swapfile-unuse_pte-can-map-random-data-if-swap-read-fails.patch
mm-swapfile-fix-lost-swap-bits-in-unuse_pte.patch
mm-madvise-free-hwpoison-and-swapin-error-entry-in-madvise_free_pte_range.patch
mm-shmem-fix-infinite-loop-when-swap-in-shmem-error-at-swapoff-time.patch
mm-filter-out-swapin-error-entry-in-shmem-mapping.patch