[merged mm-stable] mm-swap-submit-the-last-readahead-batch-before-unplugging.patch removed from -mm tree

[merged mm-stable] mm-swap-submit-the-last-readahead-batch-before-unplugging.patch removed from -mm tree

[Andrew Morton]

The quilt patch titled
     Subject: mm/swap: submit the last readahead batch before unplugging
has been removed from the -mm tree.  Its filename was
     mm-swap-submit-the-last-readahead-batch-before-unplugging.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: Alexandre Ghiti <alex@ghiti.fr>
Subject: mm/swap: submit the last readahead batch before unplugging
Date: Thu,  1 Oct 2026 10:57:12 +0200

Since block swap I/O is batched in struct swap_iocb, swap_add_folio() only
appends a folio to the pending batch when its slot directly follows the
previous one, and submits the pending batch otherwise.  Batches submitted
inside the readahead loop go through the plug, where the block layer can
still merge them, but the final batch is submitted after blk_finish_plug()
and always becomes a separate request.

So submit the final batch before finishing the plug.

Link: https://lore.kernel.org/20261001085730.2029773-1-alex@ghiti.fr
Fixes: dda8fb68b590 ("mm/swap: also use struct swap_iocb for block I/O")
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Joshua Hahn <joshua.hahnjy@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Chris Li <chrisl@kernel.org>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Baoquan He <baoquan.he@linux.dev>
Cc: Barry Song <baohua@kernel.org>
Cc: Youngjun Park <youngjun.park@lge.com>
---

 mm/swap_state.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/mm/swap_state.c~mm-swap-submit-the-last-readahead-batch-before-unplugging
+++ a/mm/swap_state.c
@@ -906,8 +906,8 @@ struct folio *swap_cluster_readahead(swp
 			continue;
 		folio_put(folio);
 	}
-	blk_finish_plug(&plug);
 	swap_read_submit(&ctx);
+	blk_finish_plug(&plug);
 skip:
 	return swap_cache_read_folio_sync(entry, gfp_mask, mpol, ilx);
 }
@@ -1019,8 +1019,8 @@ static struct folio *swap_vma_readahead(
 	}
 	if (pte)
 		pte_unmap(pte);
-	blk_finish_plug(&plug);
 	swap_read_submit(&ctx);
+	blk_finish_plug(&plug);
 skip:
 	/* The folio was likely read above, so no need for plugging here */
 	return swap_cache_read_folio_sync(targ_entry, gfp_mask, mpol, targ_ilx);
_

Patches currently in -mm which might be from alex@ghiti.fr are