On 08/28/2020 03:03 PM, Song Liu wrote:
On Mon, Aug 24, 2020 at 10:43 PM Xiao Ni <xni@xxxxxxxxxx> wrote:For far layout, the discard region is not continuous on disks. So it needs far copies r10bio to cover all regions. It needs a way to know all r10bios have finish or not. Similar with raid10_sync_request, only the first r10bio master_bio records the discard bio. Other r10bios master_bio record the first r10bio. The first r10bio can finish after other r10bios finish and then return the discard bio. Signed-off-by: Xiao Ni <xni@xxxxxxxxxx> --- drivers/md/raid10.c | 87 +++++++++++++++++++++++++++++++++++++++-------------- drivers/md/raid10.h | 1 + 2 files changed, 65 insertions(+), 23 deletions(-) diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 257791e..f6518ea 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -1534,6 +1534,29 @@ static struct bio *raid10_split_bio(struct r10conf *conf, return bio; } +static void raid_end_discard_bio(struct r10bio *r10bio)Let's name this raid10_*
Ok
The usage of while is right here. For far layout, it needs far copies r10bio. It needs to find a method to know all r10bios finish. The first r10bio->remaining is used to achieve the target. It adds the first r10bio->remaining when preparing other r10bios. I was inspired by end_sync_request. So it should use while here. It needs to decrease the first r10bio remaining for other r10bios in the second loop.+{ + struct r10conf *conf = r10bio->mddev->private; + struct r10bio *first_r10bio; + + while (atomic_dec_and_test(&r10bio->remaining)) {Should this be "if (atomic_*"?
Are there more things you want me to modify or add? If not, I'll send the v6 to rename the function
name. Thanks for reviewing these patches :) Regards Xiao
