Re: [PATCH] mm: migrate: remove unused includes

[Kefeng Wang <wangkefeng.wang@huawei.com>]

On 2024/9/5 4:54, Andrew Morton wrote:
> On Wed, 4 Sep 2024 17:58:49 +0800 Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
> 
>> Some includes are not need anymore, remove them.
>>
> 
> Please define "not needed".  Does migrate.c simply not refer to
Agree.

> anything which these headers provide?  Or does migrate.c already pick
> up these headers via nested includes?
> 
> If the latter then that can be a problem - build breakage under rare
> configs, or as code generally evolves.  Not a *big* problem - we detect
> and fix such things quickly, but I do think general good practice is to
> directly include whatever the .c file requires.

Yes, I could add more infos,

random.h not needed since commit 6c542ab75714 ("mm/demotion: build 
demotion targets based on explicit memory tiers"), all functions moved
into memory-tiers.

nsproxy.h not needed since commit 228ebcbe634a ("Uninline 
find_task_by_xxx set of functions"), no nsproxy, we only call
find_task_by_vpid() now.

hugetlb_cgroup.h not needed since commit ab5ac90aecf5 ("mm, hugetlb: do 
not rely on overcommit limit during migration"), move_hugetlb_state() is
called and it belongs to hugetlb.h, which is already included.


memremap.h, userfaultfd_k.h and oom.h are introduced for zone device
page migration, but all functions are moved into migrate_device.c, so no
needed too.