fs: nfsd: nfs4state.c: Use built-in RCU list checking

list_for_each_entry_rcu() has built-in RCU and lock checking.

Pass cond argument to list_for_each_entry_rcu() to silence
false lockdep warning when  CONFIG_PROVE_RCU_LIST is enabled
by default.
Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

fs/nfsd/nfs4state.c

@@ -4343,7 +4343,8 @@ find_file_locked(struct knfsd_fh *fh, unsigned int hashval)
 {
 	struct nfs4_file *fp;
 
-	hlist_for_each_entry_rcu(fp, &file_hashtbl[hashval], fi_hash) {
+	hlist_for_each_entry_rcu(fp, &file_hashtbl[hashval], fi_hash,
+				lockdep_is_held(&state_lock)) {
 		if (fh_match(&fp->fi_fhandle, fh)) {
 			if (refcount_inc_not_zero(&fp->fi_ref))
 				return fp;