On Wed, Feb 3, 2021 at 11:42 PM Xiao Ni <xni@xxxxxxxxxx> wrote: > > Hi Song > > Please ignore the v2 version. There is a place that needs to be fix. > I'll re-send > v2 version again. What did you change in the new v2? Removing "extern" in the header? For small changes like this, I can just update it while applying the patches. If we do need resend (for bigger changes), it's better to call it v3. I was testing the first v2 in the past hour or so, it looks good in the test. I will take a closer look tomorrow. On the other hand, we are getting close to the 5.12 merge window, so it is a little too late for bigger changes like this. Therefore, I would prefer to wait until 5.13. If you need it in 5.12 for some reason, please let me know. Thanks, Song > > Regards > Xiao > > On 02/04/2021 01:57 PM, Xiao Ni wrote: > > Hi all > > > > Now mkfs on raid10 which is combined with ssd/nvme disks takes a long time. > > This patch set tries to resolve this problem. > > > > This patch set had been reverted because of a data corruption problem. This > > version fix this problem. The root cause which causes the data corruption is > > the wrong calculation of start address of near copies disks. > > > > Now we use a similar way with raid0 to handle discard request for raid10. > > Because the discard region is very big, we can calculate the start/end > > address for each disk. Then we can submit the discard request to each disk. > > But for raid10, it has copies. For near layout, if the discard request > > doesn't align with chunk size, we calculate a start_disk_offset. Now we only > > use start_disk_offset for the first disk, but it should be used for the > > near copies disks too. > > > > [ 789.709501] discard bio start : 70968, size : 191176 > > [ 789.709507] first stripe index 69, start disk index 0, start disk offset 70968 > > [ 789.709509] last stripe index 256, end disk index 0, end disk offset 262144 > > [ 789.709511] disk 0, dev start : 70968, dev end : 262144 > > [ 789.709515] disk 1, dev start : 70656, dev end : 262144 > > > > For example, in this test case, it has 2 near copies. The start_disk_offset > > for the first disk is 70968. It should use the same offset address for second disk. > > But it uses the start address of this chunk. It discard more region. This version > > simply spilt the un-aligned part with strip size. > > > > And it fixes another problem. The calculation of stripe_size is wrong in reverted version. > > > > V2: Fix problems pointed by Christoph Hellwig. > > > > Xiao Ni (5): > > md: add md_submit_discard_bio() for submitting discard bio > > md/raid10: extend r10bio devs to raid disks > > md/raid10: pull the code that wait for blocked dev into one function > > md/raid10: improve raid10 discard request > > md/raid10: improve discard request for far layout > > > > drivers/md/md.c | 20 +++ > > drivers/md/md.h | 2 + > > drivers/md/raid0.c | 14 +- > > drivers/md/raid10.c | 434 +++++++++++++++++++++++++++++++++++++++++++++------- > > drivers/md/raid10.h | 1 + > > 5 files changed, 402 insertions(+), 69 deletions(-) > > >
