2021-03-20 11:46:38

by Miaohe Lin

Subject: [PATCH 1/5] mm/migrate.c: remove unnecessary VM_BUG_ON_PAGE on putback_movable_page()

The !PageLocked() check is implicitly done in PageMovable(). Remove this
explicit one.

Signed-off-by: Miaohe Lin <[email protected]>
---
mm/migrate.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/mm/migrate.c b/mm/migrate.c
index 47df0df8f21a..e4ca5ef508ea 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -146,7 +146,6 @@ void putback_movable_page(struct page *page)
struct address_space *mapping;

VM_BUG_ON_PAGE(!PageLocked(page), page);
- VM_BUG_ON_PAGE(!PageMovable(page), page);
VM_BUG_ON_PAGE(!PageIsolated(page), page);

mapping = page_mapping(page);
--
2.19.1

2021-03-20 14:13:27

by Rafael Aquini

Subject: Re: [PATCH 1/5] mm/migrate.c: remove unnecessary VM_BUG_ON_PAGE on putback_movable_page()

On Sat, Mar 20, 2021 at 05:36:57AM -0400, Miaohe Lin wrote:
> The !PageLocked() check is implicitly done in PageMovable(). Remove this
> explicit one.
>

I'd just keep the explicit assertion in place, regardless.
But if you're going to stick with this patch, please fix it because it's
removing the wrong assertion.


> Signed-off-by: Miaohe Lin <[email protected]>
> ---
> mm/migrate.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/mm/migrate.c b/mm/migrate.c
> index 47df0df8f21a..e4ca5ef508ea 100644
> --- a/mm/migrate.c
> +++ b/mm/migrate.c
> @@ -146,7 +146,6 @@ void putback_movable_page(struct page *page)
> struct address_space *mapping;
>
> VM_BUG_ON_PAGE(!PageLocked(page), page);
> - VM_BUG_ON_PAGE(!PageMovable(page), page);
> VM_BUG_ON_PAGE(!PageIsolated(page), page);
>
> mapping = page_mapping(page);
> --
> 2.19.1
>
>

2021-03-22 01:54:04

by Miaohe Lin

Subject: Re: [PATCH 1/5] mm/migrate.c: remove unnecessary VM_BUG_ON_PAGE on putback_movable_page()

Hi:
On 2021/3/20 22:11, Rafael Aquini wrote:
> On Sat, Mar 20, 2021 at 05:36:57AM -0400, Miaohe Lin wrote:
>> The !PageLocked() check is implicitly done in PageMovable(). Remove this
>> explicit one.
>>
>
> I'd just keep the explicit assertion in place, regardless.
> But if you're going to stick with this patch, please fix it because it's
> removing the wrong assertion.

Many thanks for your reply. I should have a coffee when I make this patch! :(
Will fix it. Many thanks for remind!

>
>
>> Signed-off-by: Miaohe Lin <[email protected]>
>> ---
>> mm/migrate.c | 1 -
>> 1 file changed, 1 deletion(-)
>>
>> diff --git a/mm/migrate.c b/mm/migrate.c
>> index 47df0df8f21a..e4ca5ef508ea 100644
>> --- a/mm/migrate.c
>> +++ b/mm/migrate.c
>> @@ -146,7 +146,6 @@ void putback_movable_page(struct page *page)
>> struct address_space *mapping;
>>
>> VM_BUG_ON_PAGE(!PageLocked(page), page);
>> - VM_BUG_ON_PAGE(!PageMovable(page), page);
>> VM_BUG_ON_PAGE(!PageIsolated(page), page);
>>
>> mapping = page_mapping(page);
>> --
>> 2.19.1
>>
>>
>
> .
>