Re: [PATCH v3 2/3] mm: move folio LRU code out of swap

[Lorenzo Stoakes <ljs@kernel.org>]

On Tue, Jun 02, 2026 at 09:01:16AM +0800, Jianyue Wu wrote:
> Rename mm/swap.c to mm/folio_lru.c so the filename better matches
> the code's main responsibility.
>
> This keeps the implementation split from swap-specific code without
> changing the published LRU helper interfaces.
>
> Update MAINTAINERS and the remaining mm/swap.c documentation references
> after the rename.
>
> Suggested-by: Baoquan He <bhe@redhat.com>
> Suggested-by: David Hildenbrand <david@kernel.org>
> Signed-off-by: Jianyue Wu <wujianyue000@gmail.com>

This LGTM, swap.c is really misleading, and we can figure out the naming-is-hard
stuff later :P

So:

Reviewed-by: Lorenzo Stoakes <ljs@kernel.org>

But also - do we want to rename swap.h to folio_lru.h? Actually that's less
clear as we have actual swap stuff in there too.

I do also need to do more work on the softleaf conversion for e.g. swapops.h.

> ---
>  Documentation/admin-guide/sysctl/vm.rst | 2 +-
>  Documentation/core-api/mm-api.rst       | 2 +-
>  MAINTAINERS                             | 3 +--
>  mm/Makefile                             | 2 +-
>  mm/{swap.c => folio_lru.c}              | 2 +-
>  5 files changed, 5 insertions(+), 6 deletions(-)
>
> diff --git a/Documentation/admin-guide/sysctl/vm.rst b/Documentation/admin-guide/sysctl/vm.rst
> index 97e12359775c..31d135e107cb 100644
> --- a/Documentation/admin-guide/sysctl/vm.rst
> +++ b/Documentation/admin-guide/sysctl/vm.rst
> @@ -20,7 +20,7 @@ of the virtual memory (VM) subsystem of the Linux kernel and
>  the writeout of dirty data to disk.
>
>  Default values and initialization routines for most of these
> -files can be found in mm/swap.c.
> +files can be found in mm/swap_state.c.
>
>  Currently, these files are in /proc/sys/vm:
>
> diff --git a/Documentation/core-api/mm-api.rst b/Documentation/core-api/mm-api.rst
> index aabdd3cba58e..d6d189b9a996 100644
> --- a/Documentation/core-api/mm-api.rst
> +++ b/Documentation/core-api/mm-api.rst
> @@ -117,7 +117,7 @@ More Memory Management Functions
>  .. #kernel-doc:: mm/hmm.c (build warnings)
>  .. kernel-doc:: mm/memremap.c
>  .. kernel-doc:: mm/hugetlb.c
> -.. kernel-doc:: mm/swap.c
> +.. kernel-doc:: mm/folio_lru.c
>  .. kernel-doc:: mm/memcontrol.c
>  .. #kernel-doc:: mm/memory-tiers.c (build warnings)
>  .. kernel-doc:: mm/shmem.c
> diff --git a/MAINTAINERS b/MAINTAINERS
> index e3ee97f5474e..6bd39e0afceb 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -16900,7 +16900,7 @@ F:	Documentation/admin-guide/mm/multigen_lru.rst
>  F:	Documentation/mm/multigen_lru.rst
>  F:	include/linux/mm_inline.h
>  F:	include/linux/mmzone.h
> -F:	mm/swap.c
> +F:	mm/folio_lru.c
>  F:	mm/vmscan.c
>  F:	mm/workingset.c
>
> @@ -17045,7 +17045,6 @@ F:	include/linux/swap.h
>  F:	include/linux/swapfile.h
>  F:	include/linux/swapops.h
>  F:	mm/page_io.c
> -F:	mm/swap.c
>  F:	mm/swap.h
>  F:	mm/swap_table.h
>  F:	mm/swap_state.c
> diff --git a/mm/Makefile b/mm/Makefile
> index eff9f9e7e061..5f712f9bbe73 100644
> --- a/mm/Makefile
> +++ b/mm/Makefile
> @@ -50,7 +50,7 @@ endif
>
>  obj-y			:= filemap.o mempool.o oom_kill.o fadvise.o \
>  			   maccess.o page-writeback.o folio-compat.o \
> -			   readahead.o swap.o truncate.o vmscan.o shrinker.o \
> +			   readahead.o folio_lru.o truncate.o vmscan.o shrinker.o \
>  			   shmem.o util.o mmzone.o vmstat.o backing-dev.o \
>  			   mm_init.o percpu.o slab_common.o \
>  			   compaction.o show_mem.o \
> diff --git a/mm/swap.c b/mm/folio_lru.c
> similarity index 99%
> rename from mm/swap.c
> rename to mm/folio_lru.c
> index e4b3dadaa6dc..7dab6a544d94 100644
> --- a/mm/swap.c
> +++ b/mm/folio_lru.c
> @@ -1,6 +1,6 @@
>  // SPDX-License-Identifier: GPL-2.0-only
>  /*
> - *  linux/mm/swap.c
> + *  linux/mm/folio_lru.c
>   *
>   *  Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
>   */
>
> --
> 2.43.0
>