Re: [PATCH] f2fs: fix to redirty page if fail to gc data page

[Jaegeuk Kim]

On Fri, Jun 03, 2016 at 01:59:15PM +0800, Chao Yu wrote:
...

> >>> Do we have another expectation?
> >>
> >> ENOMEM or EIO?
> > 
> > EIO will stop everything.
> > ENOMEM would be better to wait for a while from page reclaim?
> 
> Agree, but for ioctl path, IMO, we don't need to let user waiting for ENOMEM
> case looping.

Well, if user wanted to do a synchronous gc, we need that, IMO.

Re: [PATCH] f2fs: fix to redirty page if fail to gc data page

[Jaegeuk Kim]

On Fri, Jun 03, 2016 at 01:59:15PM +0800, Chao Yu wrote:
...

> >>> Do we have another expectation?
> >>
> >> ENOMEM or EIO?
> > 
> > EIO will stop everything.
> > ENOMEM would be better to wait for a while from page reclaim?
> 
> Agree, but for ioctl path, IMO, we don't need to let user waiting for ENOMEM
> case looping.

Well, if user wanted to do a synchronous gc, we need that, IMO.

Re: [PATCH] f2fs: fix to redirty page if fail to gc data page

[Chao Yu]

On 2016/6/3 13:17, Jaegeuk Kim wrote:
> On Fri, Jun 03, 2016 at 01:13:21PM +0800, Chao Yu wrote:
>> On 2016/6/3 13:08, Jaegeuk Kim wrote:
>>> On Tue, May 31, 2016 at 02:10:50PM +0800, Chao Yu wrote:
 Hi Jaegeuk,

 On 2016/5/30 10:37, Jaegeuk Kim wrote:
> Hi Chao,
>
> On Sat, May 21, 2016 at 01:19:11PM +0800, Chao Yu wrote:
>> From: Chao Yu 
>>
>> If we fail to move data page during foreground GC, we should give another
>> chance to writeback that page which was set dirty previously by writer.
>>
>> Signed-off-by: Chao Yu 
>> ---
>>  fs/f2fs/gc.c | 5 -
>>  1 file changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
>> index 38d56f6..ee213a8 100644
>> --- a/fs/f2fs/gc.c
>> +++ b/fs/f2fs/gc.c
>> @@ -653,12 +653,15 @@ static void move_data_page(struct inode *inode, 
>> block_t bidx, int gc_type)
>>  .page = page,
>>  .encrypted_page = NULL,
>>  };
>> +bool is_dirty = PageDirty(page);
>> +
>>  set_page_dirty(page);
>>  f2fs_wait_on_page_writeback(page, DATA, true);
>>  if (clear_page_dirty_for_io(page))
>>  inode_dec_dirty_pages(inode);
>>  set_cold_data(page);
>> -do_write_data_page();
>> +if (do_write_data_page() && is_dirty)
>> +set_page_dirty(page);
>
> If this page is truncated with -ENOENT, we don't need to set it dirty 
> again.

 Agree

> I expect that, if we get an error here, do_garbage_collect() would retry 
> FG_GC

 IIRC, you have reworked the FG_GC flows changed from an infinite loop to 
 trying
 do the movement just one time. Here, I think if there are just few of 
 blocks are
 failed to be moved, we can give one more time for retrying. How do you 
 think?
>>>
>>> Mostly I expected here -ENOENT caused by race condition.
>>
>> If we hit ENOENT case, we can pass get_valid_blocks check, so we don't need 
>> to
>> worry about this case, right?
>>
>>> Do we have another expectation?
>>
>> ENOMEM or EIO?
> 
> EIO will stop everything.
> ENOMEM would be better to wait for a while from page reclaim?

Agree, but for ioctl path, IMO, we don't need to let user waiting for ENOMEM
case looping.

> 
>>
>> Thanks,
>>
>>>
>>> Thanks,
>>>

> again.
>
> Thanks,
>
>>  clear_cold_data(page);
>>  }
>>  out:
>> -- 
>> 2.7.2
> .
>
>>> .
>>>
> .
> 

Re: [PATCH] f2fs: fix to redirty page if fail to gc data page

[Chao Yu]

On 2016/6/3 13:17, Jaegeuk Kim wrote:
> On Fri, Jun 03, 2016 at 01:13:21PM +0800, Chao Yu wrote:
>> On 2016/6/3 13:08, Jaegeuk Kim wrote:
>>> On Tue, May 31, 2016 at 02:10:50PM +0800, Chao Yu wrote:
 Hi Jaegeuk,

 On 2016/5/30 10:37, Jaegeuk Kim wrote:
> Hi Chao,
>
> On Sat, May 21, 2016 at 01:19:11PM +0800, Chao Yu wrote:
>> From: Chao Yu 
>>
>> If we fail to move data page during foreground GC, we should give another
>> chance to writeback that page which was set dirty previously by writer.
>>
>> Signed-off-by: Chao Yu 
>> ---
>>  fs/f2fs/gc.c | 5 -
>>  1 file changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
>> index 38d56f6..ee213a8 100644
>> --- a/fs/f2fs/gc.c
>> +++ b/fs/f2fs/gc.c
>> @@ -653,12 +653,15 @@ static void move_data_page(struct inode *inode, 
>> block_t bidx, int gc_type)
>>  .page = page,
>>  .encrypted_page = NULL,
>>  };
>> +bool is_dirty = PageDirty(page);
>> +
>>  set_page_dirty(page);
>>  f2fs_wait_on_page_writeback(page, DATA, true);
>>  if (clear_page_dirty_for_io(page))
>>  inode_dec_dirty_pages(inode);
>>  set_cold_data(page);
>> -do_write_data_page();
>> +if (do_write_data_page() && is_dirty)
>> +set_page_dirty(page);
>
> If this page is truncated with -ENOENT, we don't need to set it dirty 
> again.

 Agree

> I expect that, if we get an error here, do_garbage_collect() would retry 
> FG_GC

 IIRC, you have reworked the FG_GC flows changed from an infinite loop to 
 trying
 do the movement just one time. Here, I think if there are just few of 
 blocks are
 failed to be moved, we can give one more time for retrying. How do you 
 think?
>>>
>>> Mostly I expected here -ENOENT caused by race condition.
>>
>> If we hit ENOENT case, we can pass get_valid_blocks check, so we don't need 
>> to
>> worry about this case, right?
>>
>>> Do we have another expectation?
>>
>> ENOMEM or EIO?
> 
> EIO will stop everything.
> ENOMEM would be better to wait for a while from page reclaim?

Agree, but for ioctl path, IMO, we don't need to let user waiting for ENOMEM
case looping.

> 
>>
>> Thanks,
>>
>>>
>>> Thanks,
>>>

> again.
>
> Thanks,
>
>>  clear_cold_data(page);
>>  }
>>  out:
>> -- 
>> 2.7.2
> .
>
>>> .
>>>
> .
> 

Re: [PATCH] f2fs: fix to redirty page if fail to gc data page

[Jaegeuk Kim]

On Fri, Jun 03, 2016 at 01:13:21PM +0800, Chao Yu wrote:
> On 2016/6/3 13:08, Jaegeuk Kim wrote:
> > On Tue, May 31, 2016 at 02:10:50PM +0800, Chao Yu wrote:
> >> Hi Jaegeuk,
> >>
> >> On 2016/5/30 10:37, Jaegeuk Kim wrote:
> >>> Hi Chao,
> >>>
> >>> On Sat, May 21, 2016 at 01:19:11PM +0800, Chao Yu wrote:
>  From: Chao Yu 
> 
>  If we fail to move data page during foreground GC, we should give another
>  chance to writeback that page which was set dirty previously by writer.
> 
>  Signed-off-by: Chao Yu 
>  ---
>   fs/f2fs/gc.c | 5 -
>   1 file changed, 4 insertions(+), 1 deletion(-)
> 
>  diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
>  index 38d56f6..ee213a8 100644
>  --- a/fs/f2fs/gc.c
>  +++ b/fs/f2fs/gc.c
>  @@ -653,12 +653,15 @@ static void move_data_page(struct inode *inode, 
>  block_t bidx, int gc_type)
>   .page = page,
>   .encrypted_page = NULL,
>   };
>  +bool is_dirty = PageDirty(page);
>  +
>   set_page_dirty(page);
>   f2fs_wait_on_page_writeback(page, DATA, true);
>   if (clear_page_dirty_for_io(page))
>   inode_dec_dirty_pages(inode);
>   set_cold_data(page);
>  -do_write_data_page();
>  +if (do_write_data_page() && is_dirty)
>  +set_page_dirty(page);
> >>>
> >>> If this page is truncated with -ENOENT, we don't need to set it dirty 
> >>> again.
> >>
> >> Agree
> >>
> >>> I expect that, if we get an error here, do_garbage_collect() would retry 
> >>> FG_GC
> >>
> >> IIRC, you have reworked the FG_GC flows changed from an infinite loop to 
> >> trying
> >> do the movement just one time. Here, I think if there are just few of 
> >> blocks are
> >> failed to be moved, we can give one more time for retrying. How do you 
> >> think?
> > 
> > Mostly I expected here -ENOENT caused by race condition.
> 
> If we hit ENOENT case, we can pass get_valid_blocks check, so we don't need to
> worry about this case, right?
> 
> > Do we have another expectation?
> 
> ENOMEM or EIO?

EIO will stop everything.
ENOMEM would be better to wait for a while from page reclaim?

> 
> Thanks,
> 
> > 
> > Thanks,
> > 
> >>
> >>> again.
> >>>
> >>> Thanks,
> >>>
>   clear_cold_data(page);
>   }
>   out:
>  -- 
>  2.7.2
> >>> .
> >>>
> > .
> > 

Re: [PATCH] f2fs: fix to redirty page if fail to gc data page

[Jaegeuk Kim]

On Fri, Jun 03, 2016 at 01:13:21PM +0800, Chao Yu wrote:
> On 2016/6/3 13:08, Jaegeuk Kim wrote:
> > On Tue, May 31, 2016 at 02:10:50PM +0800, Chao Yu wrote:
> >> Hi Jaegeuk,
> >>
> >> On 2016/5/30 10:37, Jaegeuk Kim wrote:
> >>> Hi Chao,
> >>>
> >>> On Sat, May 21, 2016 at 01:19:11PM +0800, Chao Yu wrote:
>  From: Chao Yu 
> 
>  If we fail to move data page during foreground GC, we should give another
>  chance to writeback that page which was set dirty previously by writer.
> 
>  Signed-off-by: Chao Yu 
>  ---
>   fs/f2fs/gc.c | 5 -
>   1 file changed, 4 insertions(+), 1 deletion(-)
> 
>  diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
>  index 38d56f6..ee213a8 100644
>  --- a/fs/f2fs/gc.c
>  +++ b/fs/f2fs/gc.c
>  @@ -653,12 +653,15 @@ static void move_data_page(struct inode *inode, 
>  block_t bidx, int gc_type)
>   .page = page,
>   .encrypted_page = NULL,
>   };
>  +bool is_dirty = PageDirty(page);
>  +
>   set_page_dirty(page);
>   f2fs_wait_on_page_writeback(page, DATA, true);
>   if (clear_page_dirty_for_io(page))
>   inode_dec_dirty_pages(inode);
>   set_cold_data(page);
>  -do_write_data_page();
>  +if (do_write_data_page() && is_dirty)
>  +set_page_dirty(page);
> >>>
> >>> If this page is truncated with -ENOENT, we don't need to set it dirty 
> >>> again.
> >>
> >> Agree
> >>
> >>> I expect that, if we get an error here, do_garbage_collect() would retry 
> >>> FG_GC
> >>
> >> IIRC, you have reworked the FG_GC flows changed from an infinite loop to 
> >> trying
> >> do the movement just one time. Here, I think if there are just few of 
> >> blocks are
> >> failed to be moved, we can give one more time for retrying. How do you 
> >> think?
> > 
> > Mostly I expected here -ENOENT caused by race condition.
> 
> If we hit ENOENT case, we can pass get_valid_blocks check, so we don't need to
> worry about this case, right?
> 
> > Do we have another expectation?
> 
> ENOMEM or EIO?

EIO will stop everything.
ENOMEM would be better to wait for a while from page reclaim?

> 
> Thanks,
> 
> > 
> > Thanks,
> > 
> >>
> >>> again.
> >>>
> >>> Thanks,
> >>>
>   clear_cold_data(page);
>   }
>   out:
>  -- 
>  2.7.2
> >>> .
> >>>
> > .
> > 

Re: [PATCH] f2fs: fix to redirty page if fail to gc data page

[Chao Yu]

On 2016/6/3 13:08, Jaegeuk Kim wrote:
> On Tue, May 31, 2016 at 02:10:50PM +0800, Chao Yu wrote:
>> Hi Jaegeuk,
>>
>> On 2016/5/30 10:37, Jaegeuk Kim wrote:
>>> Hi Chao,
>>>
>>> On Sat, May 21, 2016 at 01:19:11PM +0800, Chao Yu wrote:
 From: Chao Yu 

 If we fail to move data page during foreground GC, we should give another
 chance to writeback that page which was set dirty previously by writer.

 Signed-off-by: Chao Yu 
 ---
  fs/f2fs/gc.c | 5 -
  1 file changed, 4 insertions(+), 1 deletion(-)

 diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
 index 38d56f6..ee213a8 100644
 --- a/fs/f2fs/gc.c
 +++ b/fs/f2fs/gc.c
 @@ -653,12 +653,15 @@ static void move_data_page(struct inode *inode, 
 block_t bidx, int gc_type)
.page = page,
.encrypted_page = NULL,
};
 +  bool is_dirty = PageDirty(page);
 +
set_page_dirty(page);
f2fs_wait_on_page_writeback(page, DATA, true);
if (clear_page_dirty_for_io(page))
inode_dec_dirty_pages(inode);
set_cold_data(page);
 -  do_write_data_page();
 +  if (do_write_data_page() && is_dirty)
 +  set_page_dirty(page);
>>>
>>> If this page is truncated with -ENOENT, we don't need to set it dirty again.
>>
>> Agree
>>
>>> I expect that, if we get an error here, do_garbage_collect() would retry 
>>> FG_GC
>>
>> IIRC, you have reworked the FG_GC flows changed from an infinite loop to 
>> trying
>> do the movement just one time. Here, I think if there are just few of blocks 
>> are
>> failed to be moved, we can give one more time for retrying. How do you think?
> 
> Mostly I expected here -ENOENT caused by race condition.

If we hit ENOENT case, we can pass get_valid_blocks check, so we don't need to
worry about this case, right?

> Do we have another expectation?

ENOMEM or EIO?

Thanks,

> 
> Thanks,
> 
>>
>>> again.
>>>
>>> Thanks,
>>>
clear_cold_data(page);
}
  out:
 -- 
 2.7.2
>>> .
>>>
> .
> 

Re: [PATCH] f2fs: fix to redirty page if fail to gc data page

[Chao Yu]

On 2016/6/3 13:08, Jaegeuk Kim wrote:
> On Tue, May 31, 2016 at 02:10:50PM +0800, Chao Yu wrote:
>> Hi Jaegeuk,
>>
>> On 2016/5/30 10:37, Jaegeuk Kim wrote:
>>> Hi Chao,
>>>
>>> On Sat, May 21, 2016 at 01:19:11PM +0800, Chao Yu wrote:
 From: Chao Yu 

 If we fail to move data page during foreground GC, we should give another
 chance to writeback that page which was set dirty previously by writer.

 Signed-off-by: Chao Yu 
 ---
  fs/f2fs/gc.c | 5 -
  1 file changed, 4 insertions(+), 1 deletion(-)

 diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
 index 38d56f6..ee213a8 100644
 --- a/fs/f2fs/gc.c
 +++ b/fs/f2fs/gc.c
 @@ -653,12 +653,15 @@ static void move_data_page(struct inode *inode, 
 block_t bidx, int gc_type)
.page = page,
.encrypted_page = NULL,
};
 +  bool is_dirty = PageDirty(page);
 +
set_page_dirty(page);
f2fs_wait_on_page_writeback(page, DATA, true);
if (clear_page_dirty_for_io(page))
inode_dec_dirty_pages(inode);
set_cold_data(page);
 -  do_write_data_page();
 +  if (do_write_data_page() && is_dirty)
 +  set_page_dirty(page);
>>>
>>> If this page is truncated with -ENOENT, we don't need to set it dirty again.
>>
>> Agree
>>
>>> I expect that, if we get an error here, do_garbage_collect() would retry 
>>> FG_GC
>>
>> IIRC, you have reworked the FG_GC flows changed from an infinite loop to 
>> trying
>> do the movement just one time. Here, I think if there are just few of blocks 
>> are
>> failed to be moved, we can give one more time for retrying. How do you think?
> 
> Mostly I expected here -ENOENT caused by race condition.

If we hit ENOENT case, we can pass get_valid_blocks check, so we don't need to
worry about this case, right?

> Do we have another expectation?

ENOMEM or EIO?

Thanks,

> 
> Thanks,
> 
>>
>>> again.
>>>
>>> Thanks,
>>>
clear_cold_data(page);
}
  out:
 -- 
 2.7.2
>>> .
>>>
> .
> 

Re: [PATCH] f2fs: fix to redirty page if fail to gc data page

[Jaegeuk Kim]

On Tue, May 31, 2016 at 02:10:50PM +0800, Chao Yu wrote:
> Hi Jaegeuk,
> 
> On 2016/5/30 10:37, Jaegeuk Kim wrote:
> > Hi Chao,
> > 
> > On Sat, May 21, 2016 at 01:19:11PM +0800, Chao Yu wrote:
> >> From: Chao Yu 
> >>
> >> If we fail to move data page during foreground GC, we should give another
> >> chance to writeback that page which was set dirty previously by writer.
> >>
> >> Signed-off-by: Chao Yu 
> >> ---
> >>  fs/f2fs/gc.c | 5 -
> >>  1 file changed, 4 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> >> index 38d56f6..ee213a8 100644
> >> --- a/fs/f2fs/gc.c
> >> +++ b/fs/f2fs/gc.c
> >> @@ -653,12 +653,15 @@ static void move_data_page(struct inode *inode, 
> >> block_t bidx, int gc_type)
> >>.page = page,
> >>.encrypted_page = NULL,
> >>};
> >> +  bool is_dirty = PageDirty(page);
> >> +
> >>set_page_dirty(page);
> >>f2fs_wait_on_page_writeback(page, DATA, true);
> >>if (clear_page_dirty_for_io(page))
> >>inode_dec_dirty_pages(inode);
> >>set_cold_data(page);
> >> -  do_write_data_page();
> >> +  if (do_write_data_page() && is_dirty)
> >> +  set_page_dirty(page);
> > 
> > If this page is truncated with -ENOENT, we don't need to set it dirty again.
> 
> Agree
> 
> > I expect that, if we get an error here, do_garbage_collect() would retry 
> > FG_GC
> 
> IIRC, you have reworked the FG_GC flows changed from an infinite loop to 
> trying
> do the movement just one time. Here, I think if there are just few of blocks 
> are
> failed to be moved, we can give one more time for retrying. How do you think?

Mostly I expected here -ENOENT caused by race condition.
Do we have another expectation?

Thanks,

> 
> > again.
> > 
> > Thanks,
> > 
> >>clear_cold_data(page);
> >>}
> >>  out:
> >> -- 
> >> 2.7.2
> > .
> > 

Re: [PATCH] f2fs: fix to redirty page if fail to gc data page

[Jaegeuk Kim]

On Tue, May 31, 2016 at 02:10:50PM +0800, Chao Yu wrote:
> Hi Jaegeuk,
> 
> On 2016/5/30 10:37, Jaegeuk Kim wrote:
> > Hi Chao,
> > 
> > On Sat, May 21, 2016 at 01:19:11PM +0800, Chao Yu wrote:
> >> From: Chao Yu 
> >>
> >> If we fail to move data page during foreground GC, we should give another
> >> chance to writeback that page which was set dirty previously by writer.
> >>
> >> Signed-off-by: Chao Yu 
> >> ---
> >>  fs/f2fs/gc.c | 5 -
> >>  1 file changed, 4 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> >> index 38d56f6..ee213a8 100644
> >> --- a/fs/f2fs/gc.c
> >> +++ b/fs/f2fs/gc.c
> >> @@ -653,12 +653,15 @@ static void move_data_page(struct inode *inode, 
> >> block_t bidx, int gc_type)
> >>.page = page,
> >>.encrypted_page = NULL,
> >>};
> >> +  bool is_dirty = PageDirty(page);
> >> +
> >>set_page_dirty(page);
> >>f2fs_wait_on_page_writeback(page, DATA, true);
> >>if (clear_page_dirty_for_io(page))
> >>inode_dec_dirty_pages(inode);
> >>set_cold_data(page);
> >> -  do_write_data_page();
> >> +  if (do_write_data_page() && is_dirty)
> >> +  set_page_dirty(page);
> > 
> > If this page is truncated with -ENOENT, we don't need to set it dirty again.
> 
> Agree
> 
> > I expect that, if we get an error here, do_garbage_collect() would retry 
> > FG_GC
> 
> IIRC, you have reworked the FG_GC flows changed from an infinite loop to 
> trying
> do the movement just one time. Here, I think if there are just few of blocks 
> are
> failed to be moved, we can give one more time for retrying. How do you think?

Mostly I expected here -ENOENT caused by race condition.
Do we have another expectation?

Thanks,

> 
> > again.
> > 
> > Thanks,
> > 
> >>clear_cold_data(page);
> >>}
> >>  out:
> >> -- 
> >> 2.7.2
> > .
> > 

Re: [PATCH] f2fs: fix to redirty page if fail to gc data page

[Chao Yu]

Hi Jaegeuk,

On 2016/5/30 10:37, Jaegeuk Kim wrote:
> Hi Chao,
> 
> On Sat, May 21, 2016 at 01:19:11PM +0800, Chao Yu wrote:
>> From: Chao Yu 
>>
>> If we fail to move data page during foreground GC, we should give another
>> chance to writeback that page which was set dirty previously by writer.
>>
>> Signed-off-by: Chao Yu 
>> ---
>>  fs/f2fs/gc.c | 5 -
>>  1 file changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
>> index 38d56f6..ee213a8 100644
>> --- a/fs/f2fs/gc.c
>> +++ b/fs/f2fs/gc.c
>> @@ -653,12 +653,15 @@ static void move_data_page(struct inode *inode, 
>> block_t bidx, int gc_type)
>>  .page = page,
>>  .encrypted_page = NULL,
>>  };
>> +bool is_dirty = PageDirty(page);
>> +
>>  set_page_dirty(page);
>>  f2fs_wait_on_page_writeback(page, DATA, true);
>>  if (clear_page_dirty_for_io(page))
>>  inode_dec_dirty_pages(inode);
>>  set_cold_data(page);
>> -do_write_data_page();
>> +if (do_write_data_page() && is_dirty)
>> +set_page_dirty(page);
> 
> If this page is truncated with -ENOENT, we don't need to set it dirty again.

Agree

> I expect that, if we get an error here, do_garbage_collect() would retry FG_GC

IIRC, you have reworked the FG_GC flows changed from an infinite loop to trying
do the movement just one time. Here, I think if there are just few of blocks are
failed to be moved, we can give one more time for retrying. How do you think?

> again.
> 
> Thanks,
> 
>>  clear_cold_data(page);
>>  }
>>  out:
>> -- 
>> 2.7.2
> .
> 

Re: [PATCH] f2fs: fix to redirty page if fail to gc data page

[Chao Yu]

Hi Jaegeuk,

On 2016/5/30 10:37, Jaegeuk Kim wrote:
> Hi Chao,
> 
> On Sat, May 21, 2016 at 01:19:11PM +0800, Chao Yu wrote:
>> From: Chao Yu 
>>
>> If we fail to move data page during foreground GC, we should give another
>> chance to writeback that page which was set dirty previously by writer.
>>
>> Signed-off-by: Chao Yu 
>> ---
>>  fs/f2fs/gc.c | 5 -
>>  1 file changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
>> index 38d56f6..ee213a8 100644
>> --- a/fs/f2fs/gc.c
>> +++ b/fs/f2fs/gc.c
>> @@ -653,12 +653,15 @@ static void move_data_page(struct inode *inode, 
>> block_t bidx, int gc_type)
>>  .page = page,
>>  .encrypted_page = NULL,
>>  };
>> +bool is_dirty = PageDirty(page);
>> +
>>  set_page_dirty(page);
>>  f2fs_wait_on_page_writeback(page, DATA, true);
>>  if (clear_page_dirty_for_io(page))
>>  inode_dec_dirty_pages(inode);
>>  set_cold_data(page);
>> -do_write_data_page();
>> +if (do_write_data_page() && is_dirty)
>> +set_page_dirty(page);
> 
> If this page is truncated with -ENOENT, we don't need to set it dirty again.

Agree

> I expect that, if we get an error here, do_garbage_collect() would retry FG_GC

IIRC, you have reworked the FG_GC flows changed from an infinite loop to trying
do the movement just one time. Here, I think if there are just few of blocks are
failed to be moved, we can give one more time for retrying. How do you think?

> again.
> 
> Thanks,
> 
>>  clear_cold_data(page);
>>  }
>>  out:
>> -- 
>> 2.7.2
> .
> 

Re: [PATCH] f2fs: fix to redirty page if fail to gc data page

[Jaegeuk Kim]

Hi Chao,

On Sat, May 21, 2016 at 01:19:11PM +0800, Chao Yu wrote:
> From: Chao Yu 
> 
> If we fail to move data page during foreground GC, we should give another
> chance to writeback that page which was set dirty previously by writer.
> 
> Signed-off-by: Chao Yu 
> ---
>  fs/f2fs/gc.c | 5 -
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> index 38d56f6..ee213a8 100644
> --- a/fs/f2fs/gc.c
> +++ b/fs/f2fs/gc.c
> @@ -653,12 +653,15 @@ static void move_data_page(struct inode *inode, block_t 
> bidx, int gc_type)
>   .page = page,
>   .encrypted_page = NULL,
>   };
> + bool is_dirty = PageDirty(page);
> +
>   set_page_dirty(page);
>   f2fs_wait_on_page_writeback(page, DATA, true);
>   if (clear_page_dirty_for_io(page))
>   inode_dec_dirty_pages(inode);
>   set_cold_data(page);
> - do_write_data_page();
> + if (do_write_data_page() && is_dirty)
> + set_page_dirty(page);

If this page is truncated with -ENOENT, we don't need to set it dirty again.
I expect that, if we get an error here, do_garbage_collect() would retry FG_GC
again.

Thanks,

>   clear_cold_data(page);
>   }
>  out:
> -- 
> 2.7.2

Re: [PATCH] f2fs: fix to redirty page if fail to gc data page

[Jaegeuk Kim]

Hi Chao,

On Sat, May 21, 2016 at 01:19:11PM +0800, Chao Yu wrote:
> From: Chao Yu 
> 
> If we fail to move data page during foreground GC, we should give another
> chance to writeback that page which was set dirty previously by writer.
> 
> Signed-off-by: Chao Yu 
> ---
>  fs/f2fs/gc.c | 5 -
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> index 38d56f6..ee213a8 100644
> --- a/fs/f2fs/gc.c
> +++ b/fs/f2fs/gc.c
> @@ -653,12 +653,15 @@ static void move_data_page(struct inode *inode, block_t 
> bidx, int gc_type)
>   .page = page,
>   .encrypted_page = NULL,
>   };
> + bool is_dirty = PageDirty(page);
> +
>   set_page_dirty(page);
>   f2fs_wait_on_page_writeback(page, DATA, true);
>   if (clear_page_dirty_for_io(page))
>   inode_dec_dirty_pages(inode);
>   set_cold_data(page);
> - do_write_data_page();
> + if (do_write_data_page() && is_dirty)
> + set_page_dirty(page);

If this page is truncated with -ENOENT, we don't need to set it dirty again.
I expect that, if we get an error here, do_garbage_collect() would retry FG_GC
again.

Thanks,

>   clear_cold_data(page);
>   }
>  out:
> -- 
> 2.7.2

Re: [PATCH] f2fs: fix to redirty page if fail to gc data page

[Chao Yu]

Ping,

On 2016/5/21 13:19, Chao Yu wrote:
> From: Chao Yu 
> 
> If we fail to move data page during foreground GC, we should give another
> chance to writeback that page which was set dirty previously by writer.
> 
> Signed-off-by: Chao Yu 
> ---
>  fs/f2fs/gc.c | 5 -
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> index 38d56f6..ee213a8 100644
> --- a/fs/f2fs/gc.c
> +++ b/fs/f2fs/gc.c
> @@ -653,12 +653,15 @@ static void move_data_page(struct inode *inode, block_t 
> bidx, int gc_type)
>   .page = page,
>   .encrypted_page = NULL,
>   };
> + bool is_dirty = PageDirty(page);
> +
>   set_page_dirty(page);
>   f2fs_wait_on_page_writeback(page, DATA, true);
>   if (clear_page_dirty_for_io(page))
>   inode_dec_dirty_pages(inode);
>   set_cold_data(page);
> - do_write_data_page();
> + if (do_write_data_page() && is_dirty)
> + set_page_dirty(page);
>   clear_cold_data(page);
>   }
>  out:
> 

Re: [PATCH] f2fs: fix to redirty page if fail to gc data page

[Chao Yu]

Ping,

On 2016/5/21 13:19, Chao Yu wrote:
> From: Chao Yu 
> 
> If we fail to move data page during foreground GC, we should give another
> chance to writeback that page which was set dirty previously by writer.
> 
> Signed-off-by: Chao Yu 
> ---
>  fs/f2fs/gc.c | 5 -
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> index 38d56f6..ee213a8 100644
> --- a/fs/f2fs/gc.c
> +++ b/fs/f2fs/gc.c
> @@ -653,12 +653,15 @@ static void move_data_page(struct inode *inode, block_t 
> bidx, int gc_type)
>   .page = page,
>   .encrypted_page = NULL,
>   };
> + bool is_dirty = PageDirty(page);
> +
>   set_page_dirty(page);
>   f2fs_wait_on_page_writeback(page, DATA, true);
>   if (clear_page_dirty_for_io(page))
>   inode_dec_dirty_pages(inode);
>   set_cold_data(page);
> - do_write_data_page();
> + if (do_write_data_page() && is_dirty)
> + set_page_dirty(page);
>   clear_cold_data(page);
>   }
>  out:
>