- bch2_journal_pin_update(&c->journal, trans->journal_res.seq,
- &ck->journal, bch2_btree_key_cache_journal_flush);
+ /*
+ * To minimize lock contention, we only add the journal pin here and
+ * defer pin updates to the flush callback via ->seq. Be careful not to
+ * update ->seq on nojournal commits because we don't want to update the
+ * pin to a seq that doesn't include journal updates on disk. Otherwise
+ * we risk losing the update after a crash.
+ *
+ * The only exception is if the pin is not active in the first place. We
+ * have to add the pin because journal reclaim drives key cache
+ * flushing. The flush callback will not proceed unless ->seq matches
+ * the latest pin, so make sure it starts with a consistent value.
+ */
+ if (!(insert_entry->flags & BTREE_UPDATE_NOJOURNAL) ||
+ !journal_pin_active(&ck->journal)) {
+ ck->seq = trans->journal_res.seq;
+ }
+ bch2_journal_pin_add(&c->journal, trans->journal_res.seq,
+ &ck->journal, bch2_btree_key_cache_journal_flush);