[PATCH 1/2] f2fs: remove folio_detach_private() in .invalidate_folio and .release_folio

[PATCH 1/2] f2fs: remove folio_detach_private() in .invalidate_folio and .release_folio

[Chao Yu]

We have maintain PagePrivate and page_private and page reference
w/ {set,clear}_page_private_*, it doesn't need to call
folio_detach_private() in the end of .invalidate_folio and
.release_folio, remove it and use f2fs_bug_on instead.

Signed-off-by: Chao Yu <chao@kernel.org>
---
 fs/f2fs/data.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 4946df6dd253..8b179b4bdc03 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -3737,7 +3737,8 @@ void f2fs_invalidate_folio(struct folio *folio, size_t offset, size_t length)
 			inode->i_ino == F2FS_COMPRESS_INO(sbi))
 		clear_page_private_data(&folio->page);
 
-	folio_detach_private(folio);
+	f2fs_bug_on(sbi, PagePrivate(&folio->page));
+	f2fs_bug_on(sbi, page_private(&folio->page));
 }
 
 bool f2fs_release_folio(struct folio *folio, gfp_t wait)
@@ -3759,7 +3760,9 @@ bool f2fs_release_folio(struct folio *folio, gfp_t wait)
 	clear_page_private_reference(&folio->page);
 	clear_page_private_gcing(&folio->page);
 
-	folio_detach_private(folio);
+	f2fs_bug_on(sbi, PagePrivate(&folio->page));
+	f2fs_bug_on(sbi, page_private(&folio->page));
+
 	return true;
 }
 
-- 
2.25.1

[PATCH 2/2] f2fs: clean up with {attach,detach}_page_private()

[Chao Yu]

No logic changes.

Signed-off-by: Chao Yu <chao@kernel.org>
---
 fs/f2fs/f2fs.h | 32 ++++++++------------------------
 1 file changed, 8 insertions(+), 24 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index ec8387da7f74..c378aedcadea 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1416,11 +1416,8 @@ static inline bool page_private_##name(struct page *page) \
 #define PAGE_PRIVATE_SET_FUNC(name, flagname) \
 static inline void set_page_private_##name(struct page *page) \
 { \
-	if (!PagePrivate(page)) { \
-		get_page(page); \
-		SetPagePrivate(page); \
-		set_page_private(page, 0); \
-	} \
+	if (!PagePrivate(page)) \
+		attach_page_private(page, (void *)page->private); \
 	set_bit(PAGE_PRIVATE_NOT_POINTER, &page_private(page)); \
 	set_bit(PAGE_PRIVATE_##flagname, &page_private(page)); \
 }
@@ -1429,13 +1426,8 @@ static inline void set_page_private_##name(struct page *page) \
 static inline void clear_page_private_##name(struct page *page) \
 { \
 	clear_bit(PAGE_PRIVATE_##flagname, &page_private(page)); \
-	if (page_private(page) == BIT(PAGE_PRIVATE_NOT_POINTER)) { \
-		set_page_private(page, 0); \
-		if (PagePrivate(page)) { \
-			ClearPagePrivate(page); \
-			put_page(page); \
-		}\
-	} \
+	if (page_private(page) == BIT(PAGE_PRIVATE_NOT_POINTER)) \
+		detach_page_private(page); \
 }
 
 PAGE_PRIVATE_GET_FUNC(nonpointer, NOT_POINTER);
@@ -1464,11 +1456,8 @@ static inline unsigned long get_page_private_data(struct page *page)
 
 static inline void set_page_private_data(struct page *page, unsigned long data)
 {
-	if (!PagePrivate(page)) {
-		get_page(page);
-		SetPagePrivate(page);
-		set_page_private(page, 0);
-	}
+	if (!PagePrivate(page))
+		attach_page_private(page, 0);
 	set_bit(PAGE_PRIVATE_NOT_POINTER, &page_private(page));
 	page_private(page) |= data << PAGE_PRIVATE_MAX;
 }
@@ -1476,13 +1465,8 @@ static inline void set_page_private_data(struct page *page, unsigned long data)
 static inline void clear_page_private_data(struct page *page)
 {
 	page_private(page) &= GENMASK(PAGE_PRIVATE_MAX - 1, 0);
-	if (page_private(page) == BIT(PAGE_PRIVATE_NOT_POINTER)) {
-		set_page_private(page, 0);
-		if (PagePrivate(page)) {
-			ClearPagePrivate(page);
-			put_page(page);
-		}
-	}
+	if (page_private(page) == BIT(PAGE_PRIVATE_NOT_POINTER))
+		detach_page_private(page);
 }
 
 /* For compression */
-- 
2.25.1

Re: [PATCH 1/2] f2fs: remove folio_detach_private() in .invalidate_folio and .release_folio

[Jaegeuk Kim]

On 04/10, Chao Yu wrote:
> We have maintain PagePrivate and page_private and page reference
> w/ {set,clear}_page_private_*, it doesn't need to call
> folio_detach_private() in the end of .invalidate_folio and
> .release_folio, remove it and use f2fs_bug_on instead.
> 
> Signed-off-by: Chao Yu <chao@kernel.org>
> ---
>  fs/f2fs/data.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> index 4946df6dd253..8b179b4bdc03 100644
> --- a/fs/f2fs/data.c
> +++ b/fs/f2fs/data.c
> @@ -3737,7 +3737,8 @@ void f2fs_invalidate_folio(struct folio *folio, size_t offset, size_t length)
>  			inode->i_ino == F2FS_COMPRESS_INO(sbi))
>  		clear_page_private_data(&folio->page);
>  
> -	folio_detach_private(folio);
> +	f2fs_bug_on(sbi, PagePrivate(&folio->page));
> +	f2fs_bug_on(sbi, page_private(&folio->page));

I think we can just check page_private() only.

>  }
>  
>  bool f2fs_release_folio(struct folio *folio, gfp_t wait)
> @@ -3759,7 +3760,9 @@ bool f2fs_release_folio(struct folio *folio, gfp_t wait)
>  	clear_page_private_reference(&folio->page);
>  	clear_page_private_gcing(&folio->page);
>  
> -	folio_detach_private(folio);
> +	f2fs_bug_on(sbi, PagePrivate(&folio->page));
> +	f2fs_bug_on(sbi, page_private(&folio->page));
> +
>  	return true;
>  }
>  
> -- 
> 2.25.1

Re: [PATCH 2/2] f2fs: clean up with {attach,detach}_page_private()

[Jaegeuk Kim]

On 04/10, Chao Yu wrote:
> No logic changes.
> 
> Signed-off-by: Chao Yu <chao@kernel.org>
> ---
>  fs/f2fs/f2fs.h | 32 ++++++++------------------------
>  1 file changed, 8 insertions(+), 24 deletions(-)
> 
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index ec8387da7f74..c378aedcadea 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -1416,11 +1416,8 @@ static inline bool page_private_##name(struct page *page) \
>  #define PAGE_PRIVATE_SET_FUNC(name, flagname) \
>  static inline void set_page_private_##name(struct page *page) \
>  { \
> -	if (!PagePrivate(page)) { \
> -		get_page(page); \
> -		SetPagePrivate(page); \
> -		set_page_private(page, 0); \
> -	} \
> +	if (!PagePrivate(page)) \
> +		attach_page_private(page, (void *)page->private); \

		attach_page_private(page, (void *)0);

>  	set_bit(PAGE_PRIVATE_NOT_POINTER, &page_private(page)); \
>  	set_bit(PAGE_PRIVATE_##flagname, &page_private(page)); \
>  }
> @@ -1429,13 +1426,8 @@ static inline void set_page_private_##name(struct page *page) \
>  static inline void clear_page_private_##name(struct page *page) \
>  { \
>  	clear_bit(PAGE_PRIVATE_##flagname, &page_private(page)); \
> -	if (page_private(page) == BIT(PAGE_PRIVATE_NOT_POINTER)) { \
> -		set_page_private(page, 0); \
> -		if (PagePrivate(page)) { \
> -			ClearPagePrivate(page); \
> -			put_page(page); \
> -		}\
> -	} \
> +	if (page_private(page) == BIT(PAGE_PRIVATE_NOT_POINTER)) \
> +		detach_page_private(page); \
>  }
>  
>  PAGE_PRIVATE_GET_FUNC(nonpointer, NOT_POINTER);
> @@ -1464,11 +1456,8 @@ static inline unsigned long get_page_private_data(struct page *page)
>  
>  static inline void set_page_private_data(struct page *page, unsigned long data)
>  {
> -	if (!PagePrivate(page)) {
> -		get_page(page);
> -		SetPagePrivate(page);
> -		set_page_private(page, 0);
> -	}
> +	if (!PagePrivate(page))
> +		attach_page_private(page, 0);
>  	set_bit(PAGE_PRIVATE_NOT_POINTER, &page_private(page));
>  	page_private(page) |= data << PAGE_PRIVATE_MAX;
>  }
> @@ -1476,13 +1465,8 @@ static inline void set_page_private_data(struct page *page, unsigned long data)
>  static inline void clear_page_private_data(struct page *page)
>  {
>  	page_private(page) &= GENMASK(PAGE_PRIVATE_MAX - 1, 0);
> -	if (page_private(page) == BIT(PAGE_PRIVATE_NOT_POINTER)) {
> -		set_page_private(page, 0);
> -		if (PagePrivate(page)) {
> -			ClearPagePrivate(page);
> -			put_page(page);
> -		}
> -	}
> +	if (page_private(page) == BIT(PAGE_PRIVATE_NOT_POINTER))
> +		detach_page_private(page);
>  }
>  
>  /* For compression */
> -- 
> 2.25.1

Re: [PATCH 1/2] f2fs: remove folio_detach_private() in .invalidate_folio and .release_folio

[Chao Yu]

On 2023/4/11 2:33, Jaegeuk Kim wrote:
> On 04/10, Chao Yu wrote:
>> We have maintain PagePrivate and page_private and page reference
>> w/ {set,clear}_page_private_*, it doesn't need to call
>> folio_detach_private() in the end of .invalidate_folio and
>> .release_folio, remove it and use f2fs_bug_on instead.
>>
>> Signed-off-by: Chao Yu <chao@kernel.org>
>> ---
>>   fs/f2fs/data.c | 7 +++++--
>>   1 file changed, 5 insertions(+), 2 deletions(-)
>>
>> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
>> index 4946df6dd253..8b179b4bdc03 100644
>> --- a/fs/f2fs/data.c
>> +++ b/fs/f2fs/data.c
>> @@ -3737,7 +3737,8 @@ void f2fs_invalidate_folio(struct folio *folio, size_t offset, size_t length)
>>   			inode->i_ino == F2FS_COMPRESS_INO(sbi))
>>   		clear_page_private_data(&folio->page);
>>   
>> -	folio_detach_private(folio);
>> +	f2fs_bug_on(sbi, PagePrivate(&folio->page));
>> +	f2fs_bug_on(sbi, page_private(&folio->page));
> 
> I think we can just check page_private() only.

Why? how about the case PagePrivate was set, but page_private was't? It must
be a bug as well?

Thanks,

> 
>>   }
>>   
>>   bool f2fs_release_folio(struct folio *folio, gfp_t wait)
>> @@ -3759,7 +3760,9 @@ bool f2fs_release_folio(struct folio *folio, gfp_t wait)
>>   	clear_page_private_reference(&folio->page);
>>   	clear_page_private_gcing(&folio->page);
>>   
>> -	folio_detach_private(folio);
>> +	f2fs_bug_on(sbi, PagePrivate(&folio->page));
>> +	f2fs_bug_on(sbi, page_private(&folio->page));
>> +
>>   	return true;
>>   }
>>   
>> -- 
>> 2.25.1

Re: [PATCH 2/2] f2fs: clean up with {attach,detach}_page_private()

[Chao Yu]

On 2023/4/11 2:47, Jaegeuk Kim wrote:
> On 04/10, Chao Yu wrote:
>> No logic changes.
>>
>> Signed-off-by: Chao Yu <chao@kernel.org>
>> ---
>>   fs/f2fs/f2fs.h | 32 ++++++++------------------------
>>   1 file changed, 8 insertions(+), 24 deletions(-)
>>
>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>> index ec8387da7f74..c378aedcadea 100644
>> --- a/fs/f2fs/f2fs.h
>> +++ b/fs/f2fs/f2fs.h
>> @@ -1416,11 +1416,8 @@ static inline bool page_private_##name(struct page *page) \
>>   #define PAGE_PRIVATE_SET_FUNC(name, flagname) \
>>   static inline void set_page_private_##name(struct page *page) \
>>   { \
>> -	if (!PagePrivate(page)) { \
>> -		get_page(page); \
>> -		SetPagePrivate(page); \
>> -		set_page_private(page, 0); \
>> -	} \
>> +	if (!PagePrivate(page)) \
>> +		attach_page_private(page, (void *)page->private); \
> 
> 		attach_page_private(page, (void *)0);

Correct, thanks for fixing this.

Thanks,

> 
>>   	set_bit(PAGE_PRIVATE_NOT_POINTER, &page_private(page)); \
>>   	set_bit(PAGE_PRIVATE_##flagname, &page_private(page)); \
>>   }
>> @@ -1429,13 +1426,8 @@ static inline void set_page_private_##name(struct page *page) \
>>   static inline void clear_page_private_##name(struct page *page) \
>>   { \
>>   	clear_bit(PAGE_PRIVATE_##flagname, &page_private(page)); \
>> -	if (page_private(page) == BIT(PAGE_PRIVATE_NOT_POINTER)) { \
>> -		set_page_private(page, 0); \
>> -		if (PagePrivate(page)) { \
>> -			ClearPagePrivate(page); \
>> -			put_page(page); \
>> -		}\
>> -	} \
>> +	if (page_private(page) == BIT(PAGE_PRIVATE_NOT_POINTER)) \
>> +		detach_page_private(page); \
>>   }
>>   
>>   PAGE_PRIVATE_GET_FUNC(nonpointer, NOT_POINTER);
>> @@ -1464,11 +1456,8 @@ static inline unsigned long get_page_private_data(struct page *page)
>>   
>>   static inline void set_page_private_data(struct page *page, unsigned long data)
>>   {
>> -	if (!PagePrivate(page)) {
>> -		get_page(page);
>> -		SetPagePrivate(page);
>> -		set_page_private(page, 0);
>> -	}
>> +	if (!PagePrivate(page))
>> +		attach_page_private(page, 0);
>>   	set_bit(PAGE_PRIVATE_NOT_POINTER, &page_private(page));
>>   	page_private(page) |= data << PAGE_PRIVATE_MAX;
>>   }
>> @@ -1476,13 +1465,8 @@ static inline void set_page_private_data(struct page *page, unsigned long data)
>>   static inline void clear_page_private_data(struct page *page)
>>   {
>>   	page_private(page) &= GENMASK(PAGE_PRIVATE_MAX - 1, 0);
>> -	if (page_private(page) == BIT(PAGE_PRIVATE_NOT_POINTER)) {
>> -		set_page_private(page, 0);
>> -		if (PagePrivate(page)) {
>> -			ClearPagePrivate(page);
>> -			put_page(page);
>> -		}
>> -	}
>> +	if (page_private(page) == BIT(PAGE_PRIVATE_NOT_POINTER))
>> +		detach_page_private(page);
>>   }
>>   
>>   /* For compression */
>> -- 
>> 2.25.1

Re: [PATCH 1/2] f2fs: remove folio_detach_private() in .invalidate_folio and .release_folio

[Jaegeuk Kim]

On 04/11, Chao Yu wrote:
> On 2023/4/11 2:33, Jaegeuk Kim wrote:
> > On 04/10, Chao Yu wrote:
> > > We have maintain PagePrivate and page_private and page reference
> > > w/ {set,clear}_page_private_*, it doesn't need to call
> > > folio_detach_private() in the end of .invalidate_folio and
> > > .release_folio, remove it and use f2fs_bug_on instead.
> > > 
> > > Signed-off-by: Chao Yu <chao@kernel.org>
> > > ---
> > >   fs/f2fs/data.c | 7 +++++--
> > >   1 file changed, 5 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> > > index 4946df6dd253..8b179b4bdc03 100644
> > > --- a/fs/f2fs/data.c
> > > +++ b/fs/f2fs/data.c
> > > @@ -3737,7 +3737,8 @@ void f2fs_invalidate_folio(struct folio *folio, size_t offset, size_t length)
> > >   			inode->i_ino == F2FS_COMPRESS_INO(sbi))
> > >   		clear_page_private_data(&folio->page);
> > > -	folio_detach_private(folio);
> > > +	f2fs_bug_on(sbi, PagePrivate(&folio->page));
> > > +	f2fs_bug_on(sbi, page_private(&folio->page));
> > 
> > I think we can just check page_private() only.
> 
> Why? how about the case PagePrivate was set, but page_private was't? It must
> be a bug as well?

Given the code, I think both are set all the time. My concern is someone is
not doing set/get properly. Actually, I got a panic on page_private() when
running fsstress overnight. I'm trying to reproduce it to find which bit was
set.

> 
> Thanks,
> 
> > 
> > >   }
> > >   bool f2fs_release_folio(struct folio *folio, gfp_t wait)
> > > @@ -3759,7 +3760,9 @@ bool f2fs_release_folio(struct folio *folio, gfp_t wait)
> > >   	clear_page_private_reference(&folio->page);
> > >   	clear_page_private_gcing(&folio->page);
> > > -	folio_detach_private(folio);
> > > +	f2fs_bug_on(sbi, PagePrivate(&folio->page));
> > > +	f2fs_bug_on(sbi, page_private(&folio->page));
> > > +
> > >   	return true;
> > >   }
> > > -- 
> > > 2.25.1

Re: [f2fs-dev] [PATCH 1/2] f2fs: remove folio_detach_private() in .invalidate_folio and .release_folio

[Jaegeuk Kim]

On 04/11, Jaegeuk Kim wrote:
> On 04/11, Chao Yu wrote:
> > On 2023/4/11 2:33, Jaegeuk Kim wrote:
> > > On 04/10, Chao Yu wrote:
> > > > We have maintain PagePrivate and page_private and page reference
> > > > w/ {set,clear}_page_private_*, it doesn't need to call
> > > > folio_detach_private() in the end of .invalidate_folio and
> > > > .release_folio, remove it and use f2fs_bug_on instead.
> > > > 
> > > > Signed-off-by: Chao Yu <chao@kernel.org>
> > > > ---
> > > >   fs/f2fs/data.c | 7 +++++--
> > > >   1 file changed, 5 insertions(+), 2 deletions(-)
> > > > 
> > > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> > > > index 4946df6dd253..8b179b4bdc03 100644
> > > > --- a/fs/f2fs/data.c
> > > > +++ b/fs/f2fs/data.c
> > > > @@ -3737,7 +3737,8 @@ void f2fs_invalidate_folio(struct folio *folio, size_t offset, size_t length)
> > > >   			inode->i_ino == F2FS_COMPRESS_INO(sbi))
> > > >   		clear_page_private_data(&folio->page);
> > > > -	folio_detach_private(folio);
> > > > +	f2fs_bug_on(sbi, PagePrivate(&folio->page));
> > > > +	f2fs_bug_on(sbi, page_private(&folio->page));
> > > 
> > > I think we can just check page_private() only.
> > 
> > Why? how about the case PagePrivate was set, but page_private was't? It must
> > be a bug as well?
> 
> Given the code, I think both are set all the time. My concern is someone is
> not doing set/get properly. Actually, I got a panic on page_private() when
> running fsstress overnight. I'm trying to reproduce it to find which bit was
> set.

It turned out that inline bit is somehow set, guessing the bit was not cleared
when the first dirty page was truncated or somewhere else.

Anyway, tooking a look at the usecase of flushing inline_data to inode page
aggressively, I feel it's kinda hack and may increase the checkpoint latency.
Hence, I'd like to remove it simply.

https://lore.kernel.org/linux-f2fs-devel/20230412160810.1534632-1-jaegeuk@kernel.org/T/#t

> 
> > 
> > Thanks,
> > 
> > > 
> > > >   }
> > > >   bool f2fs_release_folio(struct folio *folio, gfp_t wait)
> > > > @@ -3759,7 +3760,9 @@ bool f2fs_release_folio(struct folio *folio, gfp_t wait)
> > > >   	clear_page_private_reference(&folio->page);
> > > >   	clear_page_private_gcing(&folio->page);
> > > > -	folio_detach_private(folio);
> > > > +	f2fs_bug_on(sbi, PagePrivate(&folio->page));
> > > > +	f2fs_bug_on(sbi, page_private(&folio->page));
> > > > +
> > > >   	return true;
> > > >   }
> > > > -- 
> > > > 2.25.1
> 
> 
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