[LU-13246] osd_otable_it_next() can miss spin_unlock()

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.14.0
• Severity: 3
• Assignee: Alex Zhuravlev
• Reporter: Alex Zhuravlev

Description

osd_otable_it_next() in osd-zfs can leave the spinlock locked because of race:

	if (!scrub->os_full_speed)
		spin_lock(&scrub->os_lock);
	it->ooi_prefetched--;
	if (!scrub->os_full_speed) {
		if (scrub->os_waiting) {
			scrub->os_waiting = 0;
			wake_up_all(&thread->t_ctl_waitq);
		}
		spin_unlock(&scrub->os_lock);
	}

os_full_speed may chane in-between which sometimes happens in my testing.