bpf: Do per-instruction state dumping in verifier when log_level > 1.

If log_level > 1, do a state dump every instruction and emit it in
a more compact way (without a leading newline).

This will facilitate more sophisticated test cases which inspect the
verifier log for register state.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>

kernel/bpf/verifier.c

@@ -2926,8 +2926,12 @@ static int do_check(struct bpf_verifier_env *env)
 			goto process_bpf_exit;
 		}
 
-		if (log_level && do_print_state) {
-			verbose("\nfrom %d to %d:", prev_insn_idx, insn_idx);
+		if (log_level > 1 || (log_level && do_print_state)) {
+			if (log_level > 1)
+				verbose("%d:", insn_idx);
+			else
+				verbose("\nfrom %d to %d:",
+					prev_insn_idx, insn_idx);
 			print_verifier_state(&env->cur_state);
 			do_print_state = false;
 		}