[v2] f2fs: free_user_blocks should use reserved_segments instead
diff mbox

Message ID 1502781273-97035-1-git-send-email-yunlong.song@huawei.com
State New
Headers show

Commit Message

Yunlong Song Aug. 15, 2017, 7:14 a.m. UTC
The part (overprovision_segments - reserved_segments) can still be used for LFS
in some case, e.g., there are lots of invalid block from dirty segments, then
the part (overprovision_segments - reserved_segments) can be safely used. So
free_use_blocks should use reserved_segments instead, rather than directly use
overprovision_segments. BTW, we also add the constraint of sbi->reserved_blocks.

Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
---
 fs/f2fs/gc.h | 18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)

Comments

Yunlong Song Aug. 18, 2017, 10:02 a.m. UTC | #1
ping...

On 2017/8/15 15:14, Yunlong Song wrote:
> The part (overprovision_segments - reserved_segments) can still be used for LFS
> in some case, e.g., there are lots of invalid block from dirty segments, then
> the part (overprovision_segments - reserved_segments) can be safely used. So
> free_use_blocks should use reserved_segments instead, rather than directly use
> overprovision_segments. BTW, we also add the constraint of sbi->reserved_blocks.
>
> Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
> ---
>   fs/f2fs/gc.h | 18 +++++++++++++++---
>   1 file changed, 15 insertions(+), 3 deletions(-)
>
> diff --git a/fs/f2fs/gc.h b/fs/f2fs/gc.h
> index 9325191..542612a 100644
> --- a/fs/f2fs/gc.h
> +++ b/fs/f2fs/gc.h
> @@ -49,11 +49,23 @@ struct gc_inode_list {
>    */
>   static inline block_t free_user_blocks(struct f2fs_sb_info *sbi)
>   {
> -	if (free_segments(sbi) < overprovision_segments(sbi))
> +	block_t avail_user_block_count, free_blocks, avail_free_blocks;
> +	block_t reserved_blocks;
> +
> +	avail_user_block_count = sbi->user_block_count - sbi->reserved_blocks;
> +
> +	if (unlikely(sbi->total_valid_block_count > avail_user_block_count))
> +		return 0;
> +
> +	free_blocks = free_segments(sbi) << sbi->log_blocks_per_seg;
> +	avail_free_blocks = min(free_blocks, avail_user_block_count -
> +								sbi->total_valid_block_count);
> +	reserved_blocks = reserved_segments(sbi) << sbi->log_blocks_per_seg;
> +
> +	if (avail_free_blocks < reserved_blocks)
>   		return 0;
>   	else
> -		return (free_segments(sbi) - overprovision_segments(sbi))
> -			<< sbi->log_blocks_per_seg;
> +		return avail_free_blocks - reserved_blocks;
>   }
>   
>   static inline block_t limit_invalid_user_blocks(struct f2fs_sb_info *sbi)
Chao Yu Aug. 18, 2017, 3:19 p.m. UTC | #2
Hi Yunlong,

I think you have changed original implication of the function, IMO, it would be
more accurate to use user_free_segment_blocks instead of free_user_blocks.

Thanks,

On 2017/8/18 18:02, Yunlong Song wrote:
> ping...
> 
> On 2017/8/15 15:14, Yunlong Song wrote:
>> The part (overprovision_segments - reserved_segments) can still be used for LFS
>> in some case, e.g., there are lots of invalid block from dirty segments, then
>> the part (overprovision_segments - reserved_segments) can be safely used. So
>> free_use_blocks should use reserved_segments instead, rather than directly use
>> overprovision_segments. BTW, we also add the constraint of sbi->reserved_blocks.
>>
>> Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
>> ---
>>   fs/f2fs/gc.h | 18 +++++++++++++++---
>>   1 file changed, 15 insertions(+), 3 deletions(-)
>>
>> diff --git a/fs/f2fs/gc.h b/fs/f2fs/gc.h
>> index 9325191..542612a 100644
>> --- a/fs/f2fs/gc.h
>> +++ b/fs/f2fs/gc.h
>> @@ -49,11 +49,23 @@ struct gc_inode_list {
>>    */
>>   static inline block_t free_user_blocks(struct f2fs_sb_info *sbi)
>>   {
>> -    if (free_segments(sbi) < overprovision_segments(sbi))
>> +    block_t avail_user_block_count, free_blocks, avail_free_blocks;
>> +    block_t reserved_blocks;
>> +
>> +    avail_user_block_count = sbi->user_block_count - sbi->reserved_blocks;
>> +
>> +    if (unlikely(sbi->total_valid_block_count > avail_user_block_count))
>> +        return 0;
>> +
>> +    free_blocks = free_segments(sbi) << sbi->log_blocks_per_seg;
>> +    avail_free_blocks = min(free_blocks, avail_user_block_count -
>> +                                sbi->total_valid_block_count);
>> +    reserved_blocks = reserved_segments(sbi) << sbi->log_blocks_per_seg;
>> +
>> +    if (avail_free_blocks < reserved_blocks)
>>           return 0;
>>       else
>> -        return (free_segments(sbi) - overprovision_segments(sbi))
>> -            << sbi->log_blocks_per_seg;
>> +        return avail_free_blocks - reserved_blocks;
>>   }
>>     static inline block_t limit_invalid_user_blocks(struct f2fs_sb_info *sbi)
>

Patch
diff mbox

diff --git a/fs/f2fs/gc.h b/fs/f2fs/gc.h
index 9325191..542612a 100644
--- a/fs/f2fs/gc.h
+++ b/fs/f2fs/gc.h
@@ -49,11 +49,23 @@  struct gc_inode_list {
  */
 static inline block_t free_user_blocks(struct f2fs_sb_info *sbi)
 {
-	if (free_segments(sbi) < overprovision_segments(sbi))
+	block_t avail_user_block_count, free_blocks, avail_free_blocks;
+	block_t reserved_blocks;
+
+	avail_user_block_count = sbi->user_block_count - sbi->reserved_blocks;
+
+	if (unlikely(sbi->total_valid_block_count > avail_user_block_count))
+		return 0;
+
+	free_blocks = free_segments(sbi) << sbi->log_blocks_per_seg;
+	avail_free_blocks = min(free_blocks, avail_user_block_count -
+								sbi->total_valid_block_count);
+	reserved_blocks = reserved_segments(sbi) << sbi->log_blocks_per_seg;
+
+	if (avail_free_blocks < reserved_blocks)
 		return 0;
 	else
-		return (free_segments(sbi) - overprovision_segments(sbi))
-			<< sbi->log_blocks_per_seg;
+		return avail_free_blocks - reserved_blocks;
 }
 
 static inline block_t limit_invalid_user_blocks(struct f2fs_sb_info *sbi)