Re: [f2fs-dev] [RFC PATCH v5] f2fs: support data compression

[Chao Yu]

On 2020/1/14 0:11, Jaegeuk Kim wrote:
> On 01/13, Chao Yu wrote:
>> On 2020/1/12 2:02, Jaegeuk Kim wrote:
>>> On 01/11, Chao Yu wrote:
>>>> On 2020/1/11 7:52, Jaegeuk Kim wrote:
>>>>> On 01/06, Jaegeuk Kim wrote:
>>>>>> On 01/06, Chao Yu wrote:
>>>>>>> On 2020/1/3 14:50, Chao Yu wrote:
>>>>>>>> This works to me. Could you run fsstress tests on compressed root directory?
>>>>>>>> It seems still there are some bugs.
>>>>>>>
>>>>>>> Jaegeuk,
>>>>>>>
>>>>>>> Did you mean running por_fsstress testcase?
>>>>>>>
>>>>>>> Now, at least I didn't hit any problem for normal fsstress case.
>>>>>>
>>>>>> Yup. por_fsstress
>>>>>
>>>>> Please check https://github.com/jaegeuk/f2fs/commits/g-dev-test.
>>>>> I've fixed
>>>>> - truncation offset
>>>>> - i_compressed_blocks and its lock coverage
>>>>> - error handling
>>>>> - etc
>>>>
>>>> I changed as below, and por_fsstress stops panic the system.
>>>>
>>>> Could you merge all these fixes into original patch?
>>>
>>> Yup, let m roll up some early patches first once test results become good.
>>
>> I didn't encounter issue any more, how about por_fsstress test result in your
>> enviornment? If there is, please share the call stack with me.
> 
> Sure, will do, once I hit an issue. BTW, I'm hitting another unreacheable nat
> entry issue during por_stress without compression. :(

Did you enable any features during por_fsstress test?

I only hit below warning during por_fsstress test on image w/o compression.

------------[ cut here ]------------
WARNING: CPU: 10 PID: 33483 at fs/fs-writeback.c:1448 __writeback_single_inode+0x28c/0x340
Call Trace:
 writeback_single_inode+0xad/0x120
 sync_inode_metadata+0x3d/0x60
 f2fs_sync_inode_meta+0x90/0xe0 [f2fs]
 block_operations+0x17c/0x360 [f2fs]
 f2fs_write_checkpoint+0x101/0xff0 [f2fs]
 f2fs_sync_fs+0xa8/0x130 [f2fs]
 f2fs_do_sync_file+0x19c/0x880 [f2fs]
 do_fsync+0x38/0x60
 __x64_sys_fsync+0x10/0x20
 do_syscall_64+0x5f/0x220
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Thanks,

> 
> Thanks,
> 
>>
>> Thanks,
>>
>>>
>>>>
>>>> >From bb17d7d77fe0b8a3e3632a7026550800ab9609e9 Mon Sep 17 00:00:00 2001
>>>> From: Chao Yu <yuchao0@xxxxxxxxxx>
>>>> Date: Sat, 11 Jan 2020 16:58:20 +0800
>>>> Subject: [PATCH] f2fs: compress: fix f2fs_put_rpages_mapping()
>>>>
>>>> Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
>>>> ---
>>>>  fs/f2fs/compress.c | 30 +++++++++++++++---------------
>>>>  1 file changed, 15 insertions(+), 15 deletions(-)
>>>>
>>>> diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
>>>> index 502cd0ddc2a7..5c6a31d84ce4 100644
>>>> --- a/fs/f2fs/compress.c
>>>> +++ b/fs/f2fs/compress.c
>>>> @@ -74,18 +74,10 @@ static void f2fs_put_compressed_page(struct page *page)
>>>>  }
>>>>
>>>>  static void f2fs_drop_rpages(struct compress_ctx *cc,
>>>> -		struct address_space *mapping, int len, bool unlock)
>>>> +					int len, bool unlock)
>>>>  {
>>>>  	unsigned int i;
>>>>  	for (i = 0; i < len; i++) {
>>>> -		if (mapping) {
>>>> -			pgoff_t start = start_idx_of_cluster(cc);
>>>> -			struct page *page = find_get_page(mapping, start + i);
>>>> -
>>>> -			put_page(page);
>>>> -			put_page(page);
>>>> -			cc->rpages[i] = NULL;
>>>> -		}
>>>>  		if (!cc->rpages[i])
>>>>  			continue;
>>>>  		if (unlock)
>>>> @@ -97,18 +89,25 @@ static void f2fs_drop_rpages(struct compress_ctx *cc,
>>>>
>>>>  static void f2fs_put_rpages(struct compress_ctx *cc)
>>>>  {
>>>> -	f2fs_drop_rpages(cc, NULL, cc->cluster_size, false);
>>>> +	f2fs_drop_rpages(cc, cc->cluster_size, false);
>>>>  }
>>>>
>>>>  static void f2fs_unlock_rpages(struct compress_ctx *cc, int len)
>>>>  {
>>>> -	f2fs_drop_rpages(cc, NULL, len, true);
>>>> +	f2fs_drop_rpages(cc, len, true);
>>>>  }
>>>>
>>>>  static void f2fs_put_rpages_mapping(struct compress_ctx *cc,
>>>> -				struct address_space *mapping, int len)
>>>> +				struct address_space *mapping,
>>>> +				pgoff_t start, int len)
>>>>  {
>>>> -	f2fs_drop_rpages(cc, mapping, len, false);
>>>> +	int i;
>>>> +	for (i = 0; i < len; i++) {
>>>> +		struct page *page = find_get_page(mapping, start + i);
>>>> +
>>>> +		put_page(page);
>>>> +		put_page(page);
>>>> +	}
>>>>  }
>>>>
>>>>  static void f2fs_put_rpages_wbc(struct compress_ctx *cc,
>>>> @@ -680,7 +679,8 @@ static int prepare_compress_overwrite(struct compress_ctx *cc,
>>>>
>>>>  		if (!PageUptodate(page)) {
>>>>  			f2fs_unlock_rpages(cc, i + 1);
>>>> -			f2fs_put_rpages_mapping(cc, mapping, cc->cluster_size);
>>>> +			f2fs_put_rpages_mapping(cc, mapping, start_idx,
>>>> +					cc->cluster_size);
>>>>  			f2fs_destroy_compress_ctx(cc);
>>>>  			goto retry;
>>>>  		}
>>>> @@ -714,7 +714,7 @@ static int prepare_compress_overwrite(struct compress_ctx *cc,
>>>>  unlock_pages:
>>>>  	f2fs_unlock_rpages(cc, i);
>>>>  release_pages:
>>>> -	f2fs_put_rpages_mapping(cc, mapping, i);
>>>> +	f2fs_put_rpages_mapping(cc, mapping, start_idx, i);
>>>>  	f2fs_destroy_compress_ctx(cc);
>>>>  	return ret;
>>>>  }
>>>> -- 
>>>> 2.18.0.rc1
>>>>
>>>>
>>>>
>>>>>
>>>>> One another fix in f2fs-tools as well.
>>>>> https://github.com/jaegeuk/f2fs-tools
>>>>>
>>>>>>
>>>>>>>
>>>>>>> Thanks,
>>>>> .
>>>>>
>>> .
>>>
> .
>