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mm-shmem-return-number-of-pages-beeing-freed-in-shmem_free_swap.patch removed from -mm tree

merged mm-stable Andrew Morton 1 participant 1 message Sep 4, 2024

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The quilt patch titled
Subject: mm: shmem: return number of pages beeing freed in shmem_free_swap
has been removed from the -mm tree. Its filename was
mm-shmem-return-number-of-pages-beeing-freed-in-shmem_free_swap.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: Daniel Gomez <[email protected]>
Subject: mm: shmem: return number of pages beeing freed in shmem_free_swap
Date: Mon, 12 Aug 2024 15:42:04 +0800

Both shmem_free_swap callers expect the number of pages being freed. In the large folios context, this needs to support larger values other than 0 (used as 1 page being freed) and -ENOENT (used as 0 pages being freed). In preparation for large folios adoption, make shmem_free_swap routine return the number of pages being freed. So, returning 0 in this context, means 0 pages being freed.

While we are at it, changing to use free_swap_and_cache_nr() to free large order swap entry by Baolin Wang.

Link https://lkml.kernel.org/r/9623e863c83d749d5ab407f6fdf0a8e5a3bdf052.1723434324.git.baolin.wang@linux.alibaba.com open here
Signed-off-by Daniel Gomez <[email protected]>
Signed-off-by Baolin Wang <[email protected]>
Suggested-by Matthew Wilcox <[email protected]>
Cc Barry Song <[email protected]>
Cc Chris Li <[email protected]>
Cc David Hildenbrand <[email protected]>
Cc "Huang, Ying" <[email protected]>
Cc Hugh Dickins <[email protected]>
Cc Kefeng Wang <[email protected]>
Cc Lance Yang <[email protected]>
Cc Pankaj Raghav <[email protected]>
Cc Ryan Roberts <[email protected]>
Cc Yang Shi <[email protected]>
Cc Zi Yan <[email protected]>
Signed-off-by Andrew Morton <[email protected]>

---

 mm/shmem.c |   25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)
mm/shmem.c renamed from mm/shmem.c~mm-shmem-return-number-of-pages-beeing-freed-in-shmem_free_swap +16 -9
@@ -856,18 +856,22 @@ static void shmem_delete_from_page_cache
 }
 
 /*
- * Remove swap entry from page cache, free the swap and its page cache.
+ * Remove swap entry from page cache, free the swap and its page cache. Returns
+ * the number of pages being freed. 0 means entry not found in XArray (0 pages
+ * being freed).
  */
-static int shmem_free_swap(struct address_space *mapping,
-			   pgoff_t index, void *radswap)
+static long shmem_free_swap(struct address_space *mapping,
+			    pgoff_t index, void *radswap)
 {
+	int order = xa_get_order(&mapping->i_pages, index);
 	void *old;
 
 	old = xa_cmpxchg_irq(&mapping->i_pages, index, radswap, NULL, 0);
 	if (old != radswap)
-		return -ENOENT;
-	free_swap_and_cache(radix_to_swp_entry(radswap));
-	return 0;
+		return 0;
+	free_swap_and_cache_nr(radix_to_swp_entry(radswap), 1 << order);
+
+	return 1 << order;
 }
 
 /*

@@ -1019,7 +1023,7 @@ static void shmem_undo_range(struct inod
 			if (xa_is_value(folio)) {
 				if (unfalloc)
 					continue;
-				nr_swaps_freed += !shmem_free_swap(mapping,
+				nr_swaps_freed += shmem_free_swap(mapping,
 							indices[i], folio);
 				continue;
 			}

@@ -1086,14 +1090,17 @@ whole_folios:
 			folio = fbatch.folios[i];
 
 			if (xa_is_value(folio)) {
+				long swaps_freed;
+
 				if (unfalloc)
 					continue;
-				if (shmem_free_swap(mapping, indices[i], folio)) {
+				swaps_freed = shmem_free_swap(mapping, indices[i], folio);
+				if (!swaps_freed) {
 					/* Swap was replaced by page: retry */
 					index = indices[i];
 					break;
 				}
-				nr_swaps_freed++;
+				nr_swaps_freed += swaps_freed;
 				continue;
 			}

_

Patches currently in -mm which might be from [email protected] are