Re: [PATCH -next v2 3/7] md: delay choosing sync direction to md_start_sync()

[Yu Kuai]

Hi,

在 2023/08/15 23:54, Song Liu 写道:
> On Tue, Aug 15, 2023 at 2:00 PM Yu Kuai <yukuai1@xxxxxxxxxxxxxxx> wrote:
> [...]
> > > +
> > > +not_running:
> > > +     clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
> > > +     clear_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
> > > +     clear_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
> > > +     clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
> > > +     clear_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
> > > +     mddev_unlock(mddev);
> > > +
> > > +     wake_up(&resync_wait);
> > > +     if (test_and_clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery) &&
> > > +         mddev->sysfs_action)
> > > +             sysfs_notify_dirent_safe(mddev->sysfs_action);
> > >    }
> > >
> > >    /*
> > > @@ -9379,7 +9402,6 @@ void md_check_recovery(struct mddev *mddev)
> > >                return;
> > >
> > >        if (mddev_trylock(mddev)) {
> > > -             int spares = 0;
> > >                bool try_set_sync = mddev->safemode != 0;
> > >
> > >                if (!mddev->external && mddev->safemode == 1)
> > > @@ -9467,29 +9489,11 @@ void md_check_recovery(struct mddev *mddev)
> > >                clear_bit(MD_RECOVERY_DONE, &mddev->recovery);
> > >
> > >                if (!test_and_clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
> > > -                 test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
> > > -                     goto not_running;
> > > -             if (!md_choose_sync_direction(mddev, &spares))
> > > -                     goto not_running;
> > > -             if (mddev->pers->sync_request) {
> > > -                     if (spares) {
> > > -                             /* We are adding a device or devices to an array
> > > -                              * which has the bitmap stored on all devices.
> > > -                              * So make sure all bitmap pages get written
> > > -                              */
> > > -                             md_bitmap_write_all(mddev->bitmap);
> > > -                     }
> > > +                 test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) {
> >
> > Sorry that I made a mistake here while rebasing v2, here should be
> >
> > !test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)
> >
> > With this fixed, there are no new regression for mdadm tests using loop
> > devicein my VM.
>
>                  if (!test_and_clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
>                      !test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) {
>                          queue_work(md_misc_wq, &mddev->sync_work);
>                  } else {
>
> This doesn't look right. Should we do
>
>                  if (test_and_clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery) &&
>                      !test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) {
>                          queue_work(md_misc_wq, &mddev->sync_work);
>                  } else {
>
> instead?

Yes you're right, this is exactly what I did in v1, sorry that I keep
making mistake while rebasing.

Thanks,
Kuai

> Thanks,
> Song
> .