Re: [PATCH v2] f2fs: provide f2fs_balance_fs to __write_node_page

[Chao Yu]

Hi Yunlong,

On 2017/7/27 20:13, Yunlong Song wrote:
> v1->v2, fix some dead lock problems under some heavy load test
> 
> On 2017/7/27 20:11, Yunlong Song wrote:
>> Let node writeback also do f2fs_balance_fs to ensure there are always enough free
>> segments.

Could we cover __write_data_page of directory inode with this logic?

Thanks,

>>
>> Signed-off-by: Yunlong Song <yunlong.song@xxxxxxxxxx>
>> ---
>>   fs/f2fs/checkpoint.c |  2 +-
>>   fs/f2fs/f2fs.h       |  2 +-
>>   fs/f2fs/node.c       | 14 ++++++++------
>>   3 files changed, 10 insertions(+), 8 deletions(-)
>>
>> diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
>> index 5b876f6..3c84a25 100644
>> --- a/fs/f2fs/checkpoint.c
>> +++ b/fs/f2fs/checkpoint.c
>> @@ -1017,7 +1017,7 @@ static int block_operations(struct f2fs_sb_info *sbi)
>>   
>>   	if (get_pages(sbi, F2FS_DIRTY_NODES)) {
>>   		up_write(&sbi->node_write);
>> -		err = sync_node_pages(sbi, &wbc);
>> +		err = sync_node_pages(sbi, &wbc, false);
>>   		if (err) {
>>   			up_write(&sbi->node_change);
>>   			f2fs_unlock_all(sbi);
>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>> index 94a88b2..f69051b 100644
>> --- a/fs/f2fs/f2fs.h
>> +++ b/fs/f2fs/f2fs.h
>> @@ -2293,7 +2293,7 @@ struct page *new_node_page(struct dnode_of_data *dn,
>>   void move_node_page(struct page *node_page, int gc_type);
>>   int fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode,
>>   			struct writeback_control *wbc, bool atomic);
>> -int sync_node_pages(struct f2fs_sb_info *sbi, struct writeback_control *wbc);
>> +int sync_node_pages(struct f2fs_sb_info *sbi, struct writeback_control *wbc, bool need);
>>   void build_free_nids(struct f2fs_sb_info *sbi, bool sync, bool mount);
>>   bool alloc_nid(struct f2fs_sb_info *sbi, nid_t *nid);
>>   void alloc_nid_done(struct f2fs_sb_info *sbi, nid_t nid);
>> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
>> index d53fe62..210ec25 100644
>> --- a/fs/f2fs/node.c
>> +++ b/fs/f2fs/node.c
>> @@ -1326,7 +1326,7 @@ static struct page *last_fsync_dnode(struct f2fs_sb_info *sbi, nid_t ino)
>>   }
>>   
>>   static int __write_node_page(struct page *page, bool atomic, bool *submitted,
>> -				struct writeback_control *wbc)
>> +				struct writeback_control *wbc, bool need)
>>   {
>>   	struct f2fs_sb_info *sbi = F2FS_P_SB(page);
>>   	nid_t nid;
>> @@ -1387,6 +1387,8 @@ static int __write_node_page(struct page *page, bool atomic, bool *submitted,
>>   	}
>>   
>>   	unlock_page(page);
>> +	if (need)
>> +		f2fs_balance_fs(sbi, false);
>>   
>>   	if (unlikely(f2fs_cp_error(sbi))) {
>>   		f2fs_submit_merged_write(sbi, NODE);
>> @@ -1405,7 +1407,7 @@ static int __write_node_page(struct page *page, bool atomic, bool *submitted,
>>   static int f2fs_write_node_page(struct page *page,
>>   				struct writeback_control *wbc)
>>   {
>> -	return __write_node_page(page, false, NULL, wbc);
>> +	return __write_node_page(page, false, NULL, wbc, false);
>>   }
>>   
>>   int fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode,
>> @@ -1493,7 +1495,7 @@ int fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode,
>>   
>>   			ret = __write_node_page(page, atomic &&
>>   						page == last_page,
>> -						&submitted, wbc);
>> +						&submitted, wbc, true);
>>   			if (ret) {
>>   				unlock_page(page);
>>   				f2fs_put_page(last_page, 0);
>> @@ -1530,7 +1532,7 @@ int fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode,
>>   	return ret ? -EIO: 0;
>>   }
>>   
>> -int sync_node_pages(struct f2fs_sb_info *sbi, struct writeback_control *wbc)
>> +int sync_node_pages(struct f2fs_sb_info *sbi, struct writeback_control *wbc, bool need)
>>   {
>>   	pgoff_t index, end;
>>   	struct pagevec pvec;
>> @@ -1608,7 +1610,7 @@ int sync_node_pages(struct f2fs_sb_info *sbi, struct writeback_control *wbc)
>>   			set_fsync_mark(page, 0);
>>   			set_dentry_mark(page, 0);
>>   
>> -			ret = __write_node_page(page, false, &submitted, wbc);
>> +			ret = __write_node_page(page, false, &submitted, wbc, need);
>>   			if (ret)
>>   				unlock_page(page);
>>   			else if (submitted)
>> @@ -1697,7 +1699,7 @@ static int f2fs_write_node_pages(struct address_space *mapping,
>>   	diff = nr_pages_to_write(sbi, NODE, wbc);
>>   	wbc->sync_mode = WB_SYNC_NONE;
>>   	blk_start_plug(&plug);
>> -	sync_node_pages(sbi, wbc);
>> +	sync_node_pages(sbi, wbc, true);
>>   	blk_finish_plug(&plug);
>>   	wbc->nr_to_write = max((long)0, wbc->nr_to_write - diff);
>>   	return 0;
>