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SubjectRe: [f2fs-dev] [PATCH] f2fs: update dirty status for CURSEG as well
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Correct, I will update the patch.

On 2017/10/13 19:08, Chao Yu wrote:
> Hi Yunlong,
>
> On 2017/10/11 21:25, Yunlong Song wrote:
>> Without this patch, it will cause all the free segments using up in some
>> corner case. For example, there are 100 segments, and 20 of them are
>> reserved for ovp. If 79 segments are full of data, segment 80 becomes
>> CURSEG segment, write 512 blocks and then delete 511 blocks. Since it is
>> CURSEG segment, the __locate_dirty_segment will not update its dirty
>> status. Then the dirty_segments(sbi) is 0, f2fs_gc will fail to
>> get_victim, and f2fs_balance_fs will fail to trigger gc action. After
>> f2fs_balance_fs returns, f2fs can continue to write data to segment 81.
>> Again, segment 81 becomes CURSEG segment, write 512 blocks and delete
>> 511 blocks, the dirty_segments(sbi) is 0 and f2fs_gc fail again. This
>> can finally use up all the free segments and cause panic.
> Should we also remove the check in locate_dirty_segment?
>
> Thanks,
>
>> Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
>> ---
>> fs/f2fs/segment.c | 4 ----
>> 1 file changed, 4 deletions(-)
>>
>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
>> index bfbcff8..0ff52d5 100644
>> --- a/fs/f2fs/segment.c
>> +++ b/fs/f2fs/segment.c
>> @@ -686,10 +686,6 @@ static void __locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
>> {
>> struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
>>
>> - /* need not be added */
>> - if (IS_CURSEG(sbi, segno))
>> - return;
>> -
>> if (!test_and_set_bit(segno, dirty_i->dirty_segmap[dirty_type]))
>> dirty_i->nr_dirty[dirty_type]++;
>>
>>
> .
>

--
Thanks,
Yunlong Song


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