Re: [f2fs-dev] [PATCH] f2fs-tools: allocate logs after conventional area for HM zoned devices

[Yongpeng Yang <yangyongpeng1@oppo.com>]

On 1/31/2024 2:00 AM, Daeho Jeong wrote:
> On Mon, Jan 29, 2024 at 6:17 PM Yongpeng Yang <yangyongpeng1@oppo.com> wrote:
>>
>> cur_seg[CURSEG_COLD_DATA] will exceed end boundary of main area when:
>> device[1]: zone device size = [2 MB ~ 10MB]
>>
>> So, if there are not enough seq zones for six cursegs, we should still
>> assign 0 to c.cur_seg[CURSEG_HOT_NODE] or reserve several conv zones for
>> cursegs.
> 
> To tackle that case, how about this?
> 
>          } else if (c.zoned_mode) {
>                  c.cur_seg[CURSEG_HOT_NODE] = 0;
>                  if (c.zoned_model == F2FS_ZONED_HM) {
>                          uint32_t conv_zones =
>                                  c.devices[0].total_segments / c.segs_per_zone
>                                  - total_meta_zones;
> 
>                          if (total_zones - conv_zones >= avail_zones)
>                                  c.cur_seg[CURSEG_HOT_NODE] =
>                                          (c.devices[1].start_blkaddr -
>                                           get_sb(main_blkaddr)) / c.blks_per_seg;
>                  }
>
It seems fine, thanks.
>>
>> On 1/29/2024 11:47 PM, Daeho Jeong wrote:
>>> On Sun, Jan 28, 2024 at 5:27 PM Chao Yu <chao@kernel.org> wrote:
>>>>
>>>> On 2024/1/27 2:17, Daeho Jeong wrote:
>>>>> On Thu, Jan 25, 2024 at 5:27 PM Chao Yu <chao@kernel.org> wrote:
>>>>>>
>>>>>> On 2024/1/26 0:25, Daeho Jeong wrote:
>>>>>>> On Wed, Jan 24, 2024 at 7:34 PM Chao Yu <chao@kernel.org> wrote:
>>>>>>>>
>>>>>>>> +Cc Yongpeng Yang
>>>>>>>>
>>>>>>>> Daeho,
>>>>>>>>
>>>>>>>> Yongpeng reports a potential issue: if c.devices[0].total_segments is
>>>>>>>> larger than segments of mainarea, c.cur_seg[CURSEG_HOT_NODE] will exceed
>>>>>>>> end boundary of mainarea. Could you please check that? though it's a corner
>>>>>>>> case.
>>>>>>>
>>>>>>> Can you elaborate more?
>>>>>>
>>>>>> Since c.cur_seg[CURSEG_HOT_NODE] is an offset started from main_blkaddr.
>>>>>
>>>>> Oh, Got it.
>>>>> Then, how about this?
>>>>>
>>>>>             c.cur_seg[CURSEG_HOT_NODE] = c.zoned_model == F2FS_ZONED_HM ?
>>>>>                             (c.devices[1].start_blkaddr -
>>>>> get_sb(main_blkaddr)) / c.blks_per_seg : 0;
>>>>
>>>> Better, but log header should align to start blkaddr of zone?
>>>
>>> It's already aligned here.
>>>
>>>           if (c.zoned_mode && c.ndevs > 1)
>>>                   zone_align_start_offset +=
>>>                           (c.devices[0].total_sectors * c.sector_size) %
>>> zone_size_bytes;
>>>
>>> ...
>>>
>>>           for (i = 0; i < c.ndevs; i++) {
>>>                   if (i == 0) {
>>>                           c.devices[i].total_segments =
>>>                                   (c.devices[i].total_sectors *
>>>                                   c.sector_size - zone_align_start_offset) /
>>>                                   segment_size_bytes;
>>>                           c.devices[i].start_blkaddr = 0;
>>>                           c.devices[i].end_blkaddr = c.devices[i].total_segments *
>>>                                                   c.blks_per_seg - 1 +
>>>                                                   sb->segment0_blkaddr;
>>>                   } else {
>>>                           c.devices[i].total_segments =
>>>                                   c.devices[i].total_sectors /
>>>                                   (c.sectors_per_blk * c.blks_per_seg);
>>>                           c.devices[i].start_blkaddr =
>>>                                           c.devices[i - 1].end_blkaddr + 1;
>>>
>>> ...
>>>
>>>           total_meta_zones = ZONE_ALIGN(total_meta_segments *
>>>                                                   c.blks_per_seg);
>>>
>>>           set_sb(main_blkaddr, get_sb(segment0_blkaddr) + total_meta_zones *
>>>                                   c.segs_per_zone * c.blks_per_seg);
>>>
>>>>
>>>> Thanks,
>>>>
>>>>>
>>>>>> If c.cur_seg[CURSEG_HOT_NODE] was assigned w/ c.devices[0].total_segments,
>>>>>> and c.devices[0].total_segments is larger than segments of mainare,
>>>>>> c.cur_seg[CURSEG_HOT_NODE] will exceed the end boundary of mainarea.
>>>>>>
>>>>>>            c.cur_seg[CURSEG_HOT_NODE] = c.zoned_model == F2FS_ZONED_HM ?
>>>>>>                            c.devices[0].total_segments : 0;
>>>>>>
>>>>>>> In the case of F2FS_ZONED_HM, we have the devices[1].
>>>>>>> Do you mean the case we format the filesystem intentionally smaller
>>>>>>> than what devices have?
>>>>>>
>>>>>> I mean blew case:
>>>>>> device[0]: conventional device size = 10240 MB
>>>>>> device[1]: zone device size = 2 MB
>>>>>>
>>>>>> Thanks,
>>>>>>
>>>>>>>
>>>>>>>>
>>>>>>>> On 2024/1/18 7:00, Daeho Jeong wrote:
>>>>>>>>> From: Daeho Jeong <daehojeong@google.com>
>>>>>>>>>
>>>>>>>>> Make to allocate logs after conventional area for HM zoned devices to
>>>>>>>>> spare them for file pinning support.
>>>>>>>>>
>>>>>>>>> Signed-off-by: Daeho Jeong <daehojeong@google.com>
>>>>>>>>> ---
>>>>>>>>>       mkfs/f2fs_format.c | 3 ++-
>>>>>>>>>       1 file changed, 2 insertions(+), 1 deletion(-)
>>>>>>>>>
>>>>>>>>> diff --git a/mkfs/f2fs_format.c b/mkfs/f2fs_format.c
>>>>>>>>> index f2840c8..91a7f4b 100644
>>>>>>>>> --- a/mkfs/f2fs_format.c
>>>>>>>>> +++ b/mkfs/f2fs_format.c
>>>>>>>>> @@ -557,7 +557,8 @@ static int f2fs_prepare_super_block(void)
>>>>>>>>>                   c.cur_seg[CURSEG_COLD_DATA] = 0;
>>>>>>>>>                   c.cur_seg[CURSEG_WARM_DATA] = next_zone(CURSEG_COLD_DATA);
>>>>>>>>>           } else if (c.zoned_mode) {
>>>>>>>>> -             c.cur_seg[CURSEG_HOT_NODE] = 0;
>>>>>>>>> +             c.cur_seg[CURSEG_HOT_NODE] = c.zoned_model == F2FS_ZONED_HM ?
>>>>>>>>> +                     c.devices[0].total_segments : 0;
>>>>>>>>>                   c.cur_seg[CURSEG_WARM_NODE] = next_zone(CURSEG_HOT_NODE);
>>>>>>>>>                   c.cur_seg[CURSEG_COLD_NODE] = next_zone(CURSEG_WARM_NODE);
>>>>>>>>>                   c.cur_seg[CURSEG_HOT_DATA] = next_zone(CURSEG_COLD_NODE);