int i;
ni->nid = nid;
-
+retry:
/* Check nat cache */
down_read(&nm_i->nat_tree_lock);
e = __lookup_nat_cache(nm_i, nid);
return 0;
}
- memset(&ne, 0, sizeof(struct f2fs_nat_entry));
+ /*
+ * Check current segment summary by trying to grab journal_rwsem first.
+ * This sem is on the critical path on the checkpoint requiring the above
+ * nat_tree_lock. Therefore, we should retry, if we failed to grab here
+ * while not bothering checkpoint.
+ */
+ if (!rwsem_is_locked(&sbi->cp_global_sem)) {
+ down_read(&curseg->journal_rwsem);
+ } else if (!down_read_trylock(&curseg->journal_rwsem)) {
+ up_read(&nm_i->nat_tree_lock);
+ goto retry;
+ }
- /* Check current segment summary */
- down_read(&curseg->journal_rwsem);
i = f2fs_lookup_journal_in_cursum(journal, NAT_JOURNAL, nid, 0);
if (i >= 0) {
ne = nat_in_journal(journal, i);