+ mm-zswap-simplify-zswap_invalidate.patch added to mm-unstable branch

+ mm-zswap-simplify-zswap_invalidate.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm: zswap: simplify zswap_invalidate()
has been added to the -mm mm-unstable branch.  Its filename is
     mm-zswap-simplify-zswap_invalidate.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-zswap-simplify-zswap_invalidate.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: Johannes Weiner <hannes@cmpxchg.org>
Subject: mm: zswap: simplify zswap_invalidate()
Date: Mon, 29 Jan 2024 20:36:45 -0500

The branching is awkward and duplicates code. The comment about
writeback is also misleading: yes, the entry might have been written
back. Or it might have never been stored in zswap to begin with due to
a rejection - zswap_invalidate() is called on all exiting swap entries.

Link: https://lkml.kernel.org/r/20240130014208.565554-10-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Chengming Zhou <zhouchengming@bytedance.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/zswap.c |    9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

--- a/mm/zswap.c~mm-zswap-simplify-zswap_invalidate
+++ a/mm/zswap.c
@@ -1739,15 +1739,10 @@ void zswap_invalidate(int type, pgoff_t
 	struct zswap_tree *tree = swap_zswap_tree(swp_entry(type, offset));
 	struct zswap_entry *entry;
 
-	/* find */
 	spin_lock(&tree->lock);
 	entry = zswap_rb_search(&tree->rbroot, offset);
-	if (!entry) {
-		/* entry was written back */
-		spin_unlock(&tree->lock);
-		return;
-	}
-	zswap_invalidate_entry(tree, entry);
+	if (entry)
+		zswap_invalidate_entry(tree, entry);
 	spin_unlock(&tree->lock);
 }
 
_

Patches currently in -mm which might be from hannes@cmpxchg.org are

mm-zswap-fix-objcg-use-after-free-in-entry-destruction.patch
mm-zswap-rename-zswap_free_entry-to-zswap_entry_free.patch
mm-zswap-inline-and-remove-zswap_entry_find_get.patch
mm-zswap-move-zswap_invalidate_entry-to-related-functions.patch
mm-zswap-warn-when-referencing-a-dead-entry.patch
mm-zswap-clean-up-zswap_entry_put.patch
mm-zswap-rename-__zswap_load-to-zswap_decompress.patch
mm-zswap-break-out-zwap_compress.patch
mm-zswap-further-cleanup-zswap_store.patch
mm-zswap-simplify-zswap_invalidate.patch
mm-zswap-function-ordering-pool-alloc-free.patch
mm-zswap-function-ordering-pool-refcounting.patch
mm-zswap-function-ordering-zswap_pools.patch
mm-zswap-function-ordering-pool-params.patch
mm-zswap-function-ordering-public-lru-api.patch
mm-zswap-function-ordering-move-entry-sections-out-of-lru-section.patch
mm-zswap-function-ordering-move-entry-section-out-of-tree-section.patch
mm-zswap-function-ordering-compress-decompress-functions.patch
mm-zswap-function-ordering-per-cpu-compression-infra.patch
mm-zswap-function-ordering-writeback.patch
mm-zswap-function-ordering-shrink_memcg_cb.patch