linux.git/mm/z3fold.c, branch master

mm: z3fold: remove z3fold

2025-03-17T05:06:01+00:00

Patch series "mm: zswap: remove z3fold and zbud", v2.

After 2 cycles of deprecating z3fold, remove it as well as zbud (rationale
in specific patches).


This patch (of 2):

Z3fold has been marked as deprecated for 2 cycles and no one complained,
as expected.  As there are no known users, remove the code now.

Link: https://lkml.kernel.org/r/20250129180633.3501650-1-yosry.ahmed@linux.dev
Link: https://lkml.kernel.org/r/20250129180633.3501650-2-yosry.ahmed@linux.dev
Signed-off-by: Yosry Ahmed 
Acked-by: Johannes Weiner 
Reviewed-by: Shakeel Butt 
Acked-by: Nhat Pham 
Cc: Alexander Gordeev 
Cc: Chengming Zhou 
Cc: Christian Borntraeger 
Cc: Dan Streetman 
Cc: Heiko Carstens 
Cc: Huacai Chen 
Cc: Miaohe Lin 
Cc: Seth Jennings 
Cc: Sven Schnelle 
Cc: Vasily Gorbik 
Cc: Vitaly Wool 
Cc: Vlastimil Babka 
Cc: WANG Xuerui 
Signed-off-by: Andrew Morton

mm/z3fold: add __percpu annotation to *unbuddied pointer in struct z3fold_pool

2024-09-02T03:25:56+00:00

Compiling z3fold.c results in several sparse warnings:

z3fold.c:797:21: warning: incorrect type in initializer (different address spaces)
z3fold.c:797:21:    expected void const [noderef] __percpu *__vpp_verify
z3fold.c:797:21:    got struct list_head *
z3fold.c:852:37: warning: incorrect type in initializer (different address spaces)
z3fold.c:852:37:    expected void const [noderef] __percpu *__vpp_verify
z3fold.c:852:37:    got struct list_head *
z3fold.c:924:25: warning: incorrect type in assignment (different address spaces)
z3fold.c:924:25:    expected struct list_head *unbuddied
z3fold.c:924:25:    got void [noderef] __percpu *_res
z3fold.c:930:33: warning: incorrect type in initializer (different address spaces)
z3fold.c:930:33:    expected void const [noderef] __percpu *__vpp_verify
z3fold.c:930:33:    got struct list_head *
z3fold.c:949:25: warning: incorrect type in argument 1 (different address spaces)
z3fold.c:949:25:    expected void [noderef] __percpu *__pdata
z3fold.c:949:25:    got struct list_head *unbuddied
z3fold.c:979:25: warning: incorrect type in argument 1 (different address spaces)
z3fold.c:979:25:    expected void [noderef] __percpu *__pdata
z3fold.c:979:25:    got struct list_head *unbuddied

Add __percpu annotation to *unbuddied pointer to fix these warnings.

Link: https://lkml.kernel.org/r/20240730123445.5875-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak 
Reviewed-by: Miaohe Lin 
Cc: Vitaly Wool 
Signed-off-by: Andrew Morton

mm: zpool: return pool size in pages

2024-04-26T03:55:48+00:00

All zswap backends track their pool sizes in pages.  Currently they
multiply by PAGE_SIZE for zswap, only for zswap to divide again in order
to do limit math.  Report pages directly.

Link: https://lkml.kernel.org/r/20240312153901.3441-2-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner 
Acked-by: Yosry Ahmed 
Reviewed-by: Chengming Zhou 
Reviewed-by: Nhat Pham 
Cc: Yosry Ahmed 
Signed-off-by: Andrew Morton

mm/z3fold: fix the comment for __encode_handle()

2024-02-24T01:48:31+00:00

The comment is confusing that Pool lock should be held as this function
accesses first_num above the __encode_handle() because first_num is the
element of z3fold_header which is protected by z3fold_header->page_lock.

I found the same comment for encode_handle() in zbud.c by accident ,Pool
lock should be held as this function accesses first|last_chunks, which is
the element of zbud_header and it does not have any lock, so pool lock
should be held.

Z3fold is based on zbud, maybe the comment come from zbud, but it was
wrong, so fix it.

Link: https://lkml.kernel.org/r/20240219024453.2240147-1-hezhongkun.hzk@bytedance.com
Signed-off-by: Zhongkun He 
Cc: Johannes Weiner 
Cc: Miaohe Lin 
Cc: Vitaly Wool 
Signed-off-by: Andrew Morton

mm/z3fold: remove obsolete comment for struct z3fold_pool

2023-08-21T20:37:51+00:00

Since commit e774a7bc7f0a ("mm: zswap: remove page reclaim logic from
z3fold"), zpool and zpool_ops have been removed, so also remove the
corresponding comments.

Link: https://lkml.kernel.org/r/20230814221142.486548-1-xiujianfeng@huaweicloud.com
Signed-off-by: Xiu Jianfeng 
Reviewed-by: Miaohe Lin 
Cc: Vitaly Wool 
Signed-off-by: Andrew Morton

mm/z3fold: use helper function put_z3fold_locked() and put_z3fold_locked_list()

2023-08-21T20:37:38+00:00

This code is already duplicated six times, use helper function
put_z3fold_locked() to release z3fold page instead of open code it to help
improve code readability a bit.  And add put_z3fold_locked_list() helper
function to be consistent with it.  No functional change involved.

Link: https://lkml.kernel.org/r/20230803113824.886413-1-ruanjinjie@huawei.com
Signed-off-by: Ruan Jinjie 
Reviewed-by: Miaohe Lin 
Cc: Vitaly Wool 
Signed-off-by: Andrew Morton

mm: zswap: remove shrink from zpool interface

2023-06-19T23:19:27+00:00

Now that all three zswap backends have removed their shrink code, it is
no longer necessary for the zpool interface to include shrink/writeback
endpoints.

Link: https://lkml.kernel.org/r/20230612093815.133504-6-cerasuolodomenico@gmail.com
Signed-off-by: Domenico Cerasuolo 
Reviewed-by: Yosry Ahmed 
Acked-by: Nhat Pham 
Acked-by: Johannes Weiner 
Reviewed-by: Sergey Senozhatsky 
Cc: Dan Streetman 
Cc: Minchan Kim 
Cc: Seth Jennings 
Cc: Vitaly Wool 
Signed-off-by: Andrew Morton

mm: zswap: remove page reclaim logic from z3fold

2023-06-19T23:19:26+00:00

Switch z3fold to the new generic zswap LRU and remove its custom
implementation.

Link: https://lkml.kernel.org/r/20230612093815.133504-4-cerasuolodomenico@gmail.com
Signed-off-by: Domenico Cerasuolo 
Acked-by: Johannes Weiner 
Cc: Dan Streetman 
Cc: Minchan Kim 
Cc: Nhat Pham 
Cc: Sergey Senozhatsky 
Cc: Seth Jennings 
Cc: Vitaly Wool 
Cc: Yosry Ahmed 
Signed-off-by: Andrew Morton

mm: remove PageMovable export

2023-01-19T01:12:57+00:00

The only in-kernel users that need PageMovable() to be exported are z3fold
and zsmalloc and they are only using it for dubious debugging
functionality.  So remove those usages and the export so that no driver
code accidentally thinks that they are allowed to use this symbol.

Link: https://lkml.kernel.org/r/20230106135900.3763622-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman 
Reviewed-by: Sergey Senozhatsky 
Reviewed-by: Miaohe Lin 
Reviewed-by: David Hildenbrand 
Reviewed-by: Christoph Hellwig 
Acked-by: Minchan Kim 
Cc: Vitaly Wool 
Signed-off-by: Andrew Morton

zpool: clean out dead code

2022-12-12T02:12:10+00:00

There is a lot of provision for flexibility that isn't actually needed or
used.  Zswap (the only zpool user) always passes zpool_ops with an .evict
method set.  The backends who reclaim only do so for zswap, so they can
also directly call zpool_ops without indirection or checks.

Finally, there is no need to check the retries parameters and bail with
-EINVAL in the reclaim function, when that's called just a few lines below
with a hard-coded 8.  There is no need to duplicate the evictable and
sleep_mapped attrs from the driver in zpool_ops.

Link: https://lkml.kernel.org/r/20221128191616.1261026-3-nphamcs@gmail.com
Reviewed-by: Sergey Senozhatsky 
Signed-off-by: Johannes Weiner 
Signed-off-by: Nhat Pham 
Cc: Dan Streetman 
Cc: Minchan Kim 
Cc: Nitin Gupta 
Cc: Seth Jennings 
Cc: Vitaly Wool 
Signed-off-by: Andrew Morton