On 2017/11/30 10:42, Yunlong Song wrote:
> SSR can make hot/warm/cold nodes written together, so why should we account
> them different?
Current segment which is using ssr allocation has only one valid type, so we
can not write data/node with different type into current segment which already
has fixed type, right?
Thanks,
>
> On 2017/11/29 19:56, Chao Yu wrote:
>> On 2017/11/27 14:54, Yunlong Song wrote:
>>> Sometimes f2fs_gc is called with no target victim (e.g. xfstest
>>> generic/027, ndirty_node:545 ndiry_dent:1 ndirty_imeta:513 rsvd_segs:21
>>> free_segs:27, has_not_enough_free_secs will return true). This patch
>>> first merges pages and then converts into sections.
>> I don't think this could be right, IMO, instead, it would be better to
>> account dirty hot/warm/cold nodes or imeta separately, as actually, they
>> will use different section, but currently, our calculation way is based
>> on that they could be written to same section.
>>
>> Thanks,
>>
>>> Signed-off-by: Yunlong Song <yunlong.song@xxxxxxxxxx>
>>> ---
>>> fs/f2fs/f2fs.h | 9 ---------
>>> fs/f2fs/segment.c | 12 +++++++-----
>>> fs/f2fs/segment.h | 13 +++++++++----
>>> 3 files changed, 16 insertions(+), 18 deletions(-)
>>>
>>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>>> index ca6b0c9..e89cff7 100644
>>> --- a/fs/f2fs/f2fs.h
>>> +++ b/fs/f2fs/f2fs.h
>>> @@ -1675,15 +1675,6 @@ static inline int get_dirty_pages(struct inode *inode)
>>> return atomic_read(&F2FS_I(inode)->dirty_pages);
>>> }
>>>
>>> -static inline int get_blocktype_secs(struct f2fs_sb_info *sbi, int block_type)
>>> -{
>>> - unsigned int pages_per_sec = sbi->segs_per_sec * sbi->blocks_per_seg;
>>> - unsigned int segs = (get_pages(sbi, block_type) + pages_per_sec - 1) >>
>>> - sbi->log_blocks_per_seg;
>>> -
>>> - return segs / sbi->segs_per_sec;
>>> -}
>>> -
>>> static inline block_t valid_user_blocks(struct f2fs_sb_info *sbi)
>>> {
>>> return sbi->total_valid_block_count;
>>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
>>> index c117e09..603f805 100644
>>> --- a/fs/f2fs/segment.c
>>> +++ b/fs/f2fs/segment.c
>>> @@ -171,17 +171,19 @@ static unsigned long __find_rev_next_zero_bit(const unsigned long *addr,
>>>
>>> bool need_SSR(struct f2fs_sb_info *sbi)
>>> {
>>> - int node_secs = get_blocktype_secs(sbi, F2FS_DIRTY_NODES);
>>> - int dent_secs = get_blocktype_secs(sbi, F2FS_DIRTY_DENTS);
>>> - int imeta_secs = get_blocktype_secs(sbi, F2FS_DIRTY_IMETA);
>>> + s64 node_pages = get_pages(sbi, F2FS_DIRTY_NODES);
>>> + s64 dent_pages = get_pages(sbi, F2FS_DIRTY_DENTS);
>>> + s64 imeta_pages = get_pages(sbi, F2FS_DIRTY_IMETA);
>>>
>>> if (test_opt(sbi, LFS))
>>> return false;
>>> if (sbi->gc_thread && sbi->gc_thread->gc_urgent)
>>> return true;
>>>
>>> - return free_sections(sbi) <= (node_secs + 2 * dent_secs + imeta_secs +
>>> - SM_I(sbi)->min_ssr_sections + reserved_sections(sbi));
>>> + return free_sections(sbi) <=
>>> + (PAGE2SEC(sbi, node_pages + imeta_pages) +
>>> + PAGE2SEC(sbi, 2 * dent_pages) +
>>> + SM_I(sbi)->min_ssr_sections + reserved_sections(sbi));
>>> }
>>>
>>> void register_inmem_page(struct inode *inode, struct page *page)
>>> diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
>>> index d1d394c..723d79e 100644
>>> --- a/fs/f2fs/segment.h
>>> +++ b/fs/f2fs/segment.h
>>> @@ -115,6 +115,10 @@
>>> #define SECTOR_TO_BLOCK(sectors) \
>>> ((sectors) >> F2FS_LOG_SECTORS_PER_BLOCK)
>>>
>>> +#define PAGE2SEC(sbi, pages) \
>>> + ((((pages) + BLKS_PER_SEC(sbi) - 1) \
>>> + >> sbi->log_blocks_per_seg) / sbi->segs_per_sec)
>>> +
>>> /*
>>> * indicate a block allocation direction: RIGHT and LEFT.
>>> * RIGHT means allocating new sections towards the end of volume.
>>> @@ -527,9 +531,9 @@ static inline bool has_curseg_enough_space(struct f2fs_sb_info *sbi)
>>> static inline bool has_not_enough_free_secs(struct f2fs_sb_info *sbi,
>>> int freed, int needed)
>>> {
>>> - int node_secs = get_blocktype_secs(sbi, F2FS_DIRTY_NODES);
>>> - int dent_secs = get_blocktype_secs(sbi, F2FS_DIRTY_DENTS);
>>> - int imeta_secs = get_blocktype_secs(sbi, F2FS_DIRTY_IMETA);
>>> + s64 node_pages = get_pages(sbi, F2FS_DIRTY_NODES);
>>> + s64 dent_pages = get_pages(sbi, F2FS_DIRTY_DENTS);
>>> + s64 imeta_pages = get_pages(sbi, F2FS_DIRTY_IMETA);
>>>
>>> if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
>>> return false;
>>> @@ -538,7 +542,8 @@ static inline bool has_not_enough_free_secs(struct f2fs_sb_info *sbi,
>>> has_curseg_enough_space(sbi))
>>> return false;
>>> return (free_sections(sbi) + freed) <=
>>> - (node_secs + 2 * dent_secs + imeta_secs +
>>> + (PAGE2SEC(sbi, node_pages + imeta_pages) +
>>> + PAGE2SEC(sbi, 2 * dent_pages) +
>>> reserved_sections(sbi) + needed);
>>> }
>>>
>>>
>> .
>>
>
