+ mm-zswap-cleanup-zswap_reclaim_entry.patch added to mm-unstable branch

+ mm-zswap-cleanup-zswap_reclaim_entry.patch added to mm-unstable branch

[Andrew Morton]

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

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-zswap-cleanup-zswap_reclaim_entry.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: Chengming Zhou <zhouchengming@bytedance.com>
Subject: mm/zswap: cleanup zswap_reclaim_entry()
Date: Wed, 13 Dec 2023 04:18:02 +0000

Also after the common decompress part goes to __zswap_load(), we can
cleanup the zswap_reclaim_entry() a little.

Link: https://lkml.kernel.org/r/20231213-zswap-dstmem-v1-5-896763369d04@bytedance.com
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Cc: Chris Li <chriscli@google.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/zswap.c |   23 +++++------------------
 1 file changed, 5 insertions(+), 18 deletions(-)

--- a/mm/zswap.c~mm-zswap-cleanup-zswap_reclaim_entry
+++ a/mm/zswap.c
@@ -1449,7 +1449,6 @@ static int zswap_writeback_entry(struct
 	struct page *page;
 	struct mempolicy *mpol;
 	bool page_was_allocated;
-	int ret;
 	struct writeback_control wbc = {
 		.sync_mode = WB_SYNC_NONE,
 	};
@@ -1458,16 +1457,13 @@ static int zswap_writeback_entry(struct
 	mpol = get_task_policy(current);
 	page = __read_swap_cache_async(swpentry, GFP_KERNEL, mpol,
 				NO_INTERLEAVE_INDEX, &page_was_allocated, true);
-	if (!page) {
-		ret = -ENOMEM;
-		goto fail;
-	}
+	if (!page)
+		return -ENOMEM;
 
 	/* Found an existing page, we raced with load/swapin */
 	if (!page_was_allocated) {
 		put_page(page);
-		ret = -EEXIST;
-		goto fail;
+		return -EEXIST;
 	}
 
 	/*
@@ -1481,8 +1477,7 @@ static int zswap_writeback_entry(struct
 	if (zswap_rb_search(&tree->rbroot, swp_offset(entry->swpentry)) != entry) {
 		spin_unlock(&tree->lock);
 		delete_from_swap_cache(page_folio(page));
-		ret = -ENOMEM;
-		goto fail;
+		return -ENOMEM;
 	}
 	spin_unlock(&tree->lock);
 
@@ -1498,15 +1493,7 @@ static int zswap_writeback_entry(struct
 	__swap_writepage(page, &wbc);
 	put_page(page);
 
-	return ret;
-
-fail:
-	/*
-	 * If we get here because the page is already in swapcache, a
-	 * load may be happening concurrently. It is safe and okay to
-	 * not free the entry. It is also okay to return !0.
-	 */
-	return ret;
+	return 0;
 }
 
 static int zswap_is_page_same_filled(void *ptr, unsigned long *value)
_

Patches currently in -mm which might be from zhouchengming@bytedance.com are

mm-zswap-reuse-dstmem-when-decompress.patch
mm-zswap-change-dstmem-size-to-one-page.patch
mm-zswap-refactor-out-__zswap_load.patch
mm-zswap-cleanup-zswap_load.patch
mm-zswap-cleanup-zswap_reclaim_entry.patch