Re: [PATCH] f2fs: add bio cache for IPU
From: Chao Yu
Date: Thu Nov 15 2018 - 03:32:48 EST
Hi Jaeguek,
On 2018/11/15 15:52, Jaegeuk Kim wrote:
> Hi Chao,
>
> I suspect this brings a system stuck by missing bio being flushed. Please check
> the changes.
Oh, let me check this patch.
Thanks,
>
> Thanks,
>
> On 10/23, Chao Yu wrote:
>> SQLite in Wal mode may trigger sequential IPU write in db-wal file, after
>> commit d1b3e72d5490 ("f2fs: submit bio of in-place-update pages"), we
>> lost the chance of merging page in inner managed bio cache, result in
>> submitting more small-sized IO.
>>
>> So let's add temporary bio in writepages() to cache mergeable write IO as
>> much as possible.
>>
>> Test case:
>> 1. xfs_io -f /mnt/f2fs/file -c "pwrite 0 65536" -c "fsync"
>> 2. xfs_io -f /mnt/f2fs/file -c "pwrite 0 65536" -c "fsync"
>>
>> Before:
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65544, size = 4096
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65552, size = 4096
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65560, size = 4096
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65568, size = 4096
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65576, size = 4096
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65584, size = 4096
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65592, size = 4096
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65600, size = 4096
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65608, size = 4096
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65616, size = 4096
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65624, size = 4096
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65632, size = 4096
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65640, size = 4096
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65648, size = 4096
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65656, size = 4096
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65664, size = 4096
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), NODE, sector = 57352, size = 4096
>>
>> After:
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), DATA, sector = 65544, size = 65536
>> f2fs_submit_write_bio: dev = (251,0)/(251,0), rw = WRITE(S), NODE, sector = 57368, size = 4096
>>
>> Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
>> ---
>> fs/f2fs/data.c | 57 +++++++++++++++++++++++++++++++++++++++++++++--
>> fs/f2fs/f2fs.h | 3 +++
>> fs/f2fs/segment.c | 5 ++++-
>> 3 files changed, 62 insertions(+), 3 deletions(-)
>>
>> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
>> index 01b7f59523dc..0c8f18dc140d 100644
>> --- a/fs/f2fs/data.c
>> +++ b/fs/f2fs/data.c
>> @@ -491,6 +491,49 @@ int f2fs_submit_page_bio(struct f2fs_io_info *fio)
>> return 0;
>> }
>>
>> +int f2fs_merge_page_bio(struct f2fs_io_info *fio)
>> +{
>> + struct bio *bio = *fio->bio;
>> + struct page *page = fio->encrypted_page ?
>> + fio->encrypted_page : fio->page;
>> +
>> + if (!f2fs_is_valid_blkaddr(fio->sbi, fio->new_blkaddr,
>> + __is_meta_io(fio) ? META_GENERIC : DATA_GENERIC))
>> + return -EFAULT;
>> +
>> + trace_f2fs_submit_page_bio(page, fio);
>> + f2fs_trace_ios(fio, 0);
>> +
>> + if (bio && (*fio->last_block + 1 != fio->new_blkaddr ||
>> + !__same_bdev(fio->sbi, fio->new_blkaddr, bio))) {
>> + __submit_bio(fio->sbi, bio, fio->type);
>> + bio = NULL;
>> + }
>> +alloc_new:
>> + if (!bio) {
>> + bio = __bio_alloc(fio->sbi, fio->new_blkaddr, fio->io_wbc,
>> + BIO_MAX_PAGES, false, fio->type, fio->temp);
>> + *fio->last_block = fio->new_blkaddr;
>> + bio_set_op_attrs(bio, fio->op, fio->op_flags);
>> + }
>> +
>> + if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
>> + __submit_bio(fio->sbi, bio, fio->type);
>> + bio = NULL;
>> + goto alloc_new;
>> + }
>> +
>> + if (fio->io_wbc)
>> + wbc_account_io(fio->io_wbc, page, PAGE_SIZE);
>> +
>> + *fio->last_block = fio->new_blkaddr;
>> +
>> + inc_page_count(fio->sbi, WB_DATA_TYPE(fio->page));
>> +
>> + *fio->bio = bio;
>> + return 0;
>> +}
>> +
>> void f2fs_submit_page_write(struct f2fs_io_info *fio)
>> {
>> struct f2fs_sb_info *sbi = fio->sbi;
>> @@ -1899,6 +1942,8 @@ int f2fs_do_write_data_page(struct f2fs_io_info *fio)
>> }
>>
>> static int __write_data_page(struct page *page, bool *submitted,
>> + struct bio **bio,
>> + sector_t *last_block,
>> struct writeback_control *wbc,
>> enum iostat_type io_type)
>> {
>> @@ -1924,6 +1969,8 @@ static int __write_data_page(struct page *page, bool *submitted,
>> .need_lock = LOCK_RETRY,
>> .io_type = io_type,
>> .io_wbc = wbc,
>> + .bio = bio,
>> + .last_block = last_block,
>> };
>>
>> trace_f2fs_writepage(page, DATA);
>> @@ -2051,7 +2098,7 @@ static int __write_data_page(struct page *page, bool *submitted,
>> static int f2fs_write_data_page(struct page *page,
>> struct writeback_control *wbc)
>> {
>> - return __write_data_page(page, NULL, wbc, FS_DATA_IO);
>> + return __write_data_page(page, NULL, NULL, NULL, wbc, FS_DATA_IO);
>> }
>>
>> /*
>> @@ -2067,6 +2114,8 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
>> int done = 0;
>> struct pagevec pvec;
>> struct f2fs_sb_info *sbi = F2FS_M_SB(mapping);
>> + struct bio *bio = NULL;
>> + sector_t last_block;
>> int nr_pages;
>> pgoff_t uninitialized_var(writeback_index);
>> pgoff_t index;
>> @@ -2154,7 +2203,8 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
>> if (!clear_page_dirty_for_io(page))
>> goto continue_unlock;
>>
>> - ret = __write_data_page(page, &submitted, wbc, io_type);
>> + ret = __write_data_page(page, &submitted, &bio,
>> + &last_block, wbc, io_type);
>> if (unlikely(ret)) {
>> /*
>> * keep nr_to_write, since vfs uses this to
>> @@ -2201,6 +2251,9 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
>> if (nwritten)
>> f2fs_submit_merged_write_cond(F2FS_M_SB(mapping), mapping->host,
>> NULL, 0, DATA);
>> + /* submit cached bio of IPU write */
>> + if (bio)
>> + __submit_bio(sbi, bio, DATA);
>>
>> return ret;
>> }
>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>> index 8932276015f9..6af2a105529d 100644
>> --- a/fs/f2fs/f2fs.h
>> +++ b/fs/f2fs/f2fs.h
>> @@ -1042,6 +1042,8 @@ struct f2fs_io_info {
>> bool retry; /* need to reallocate block address */
>> enum iostat_type io_type; /* io type */
>> struct writeback_control *io_wbc; /* writeback control */
>> + struct bio **bio; /* bio for ipu */
>> + sector_t *last_block; /* last block number in bio */
>> unsigned char version; /* version of the node */
>> };
>>
>> @@ -3085,6 +3087,7 @@ void f2fs_submit_merged_write_cond(struct f2fs_sb_info *sbi,
>> nid_t ino, enum page_type type);
>> void f2fs_flush_merged_writes(struct f2fs_sb_info *sbi);
>> int f2fs_submit_page_bio(struct f2fs_io_info *fio);
>> +int f2fs_merge_page_bio(struct f2fs_io_info *fio);
>> void f2fs_submit_page_write(struct f2fs_io_info *fio);
>> struct block_device *f2fs_target_device(struct f2fs_sb_info *sbi,
>> block_t blk_addr, struct bio *bio);
>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
>> index 3aa2f00262b3..b51b182dd7f4 100644
>> --- a/fs/f2fs/segment.c
>> +++ b/fs/f2fs/segment.c
>> @@ -3194,7 +3194,10 @@ int f2fs_inplace_write_data(struct f2fs_io_info *fio)
>>
>> stat_inc_inplace_blocks(fio->sbi);
>>
>> - err = f2fs_submit_page_bio(fio);
>> + if (fio->bio)
>> + err = f2fs_merge_page_bio(fio);
>> + else
>> + err = f2fs_submit_page_bio(fio);
>> if (!err)
>> update_device_state(fio);
>>
>> --
>> 2.18.0.rc1
>
> .
>