Due to an iput race, the "unlink wait for open on other mount"
subtest can fail. If the unlink happens inline, then the test
passes. But if the orphan scanner has to complete the unlink
work, it's possible that there won't be enough log merge work
for the scanner to do the cleanup before we look at the seq index.
Add SCOUTFS_TRIGGER_LOG_MERGE_FORCE_FINALIZE_OURS, to allow
forcing a log merge. Add new counters, log_merges_start and
log_merge_complete, so that tests can see that a merge has happened.
Then we have to wait for the orphan scanner to do its work.
Add a new counter, orphan_scan_empty, that increments each time
the scanner walks the entire inode space without finding any
orphans. Once the test sees that counter increment, it should be
safe to check the seq index and see that the unlinked inode is gone.
Signed-off-by: Chris Kirby <ckirby@versity.com>
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