1// SPDX-License-Identifier: GPL-2.0-only 2/* Copyright (c) 2020 Facebook */ 3#include <stddef.h> 4#include <linux/bpf.h> 5#include <bpf/bpf_helpers.h> 6#include "bpf_misc.h" 7 8#define MAX_STACK (512 - 3 * 32) 9 10static __attribute__ ((noinline)) 11int f0(int var, struct __sk_buff *skb) 12{ 13 return skb->len; 14} 15 16__attribute__ ((noinline)) 17int f1(struct __sk_buff *skb) 18{ 19 volatile char buf[MAX_STACK] = {}; 20 21 __sink(buf[MAX_STACK - 1]); 22 23 return f0(0, skb) + skb->len; 24} 25 26int f3(int, struct __sk_buff *skb, int); 27 28__attribute__ ((noinline)) 29int f2(int val, struct __sk_buff *skb) 30{ 31 return f1(skb) + f3(val, skb, 1); 32} 33 34__attribute__ ((noinline)) 35int f3(int val, struct __sk_buff *skb, int var) 36{ 37 volatile char buf[MAX_STACK] = {}; 38 39 __sink(buf[MAX_STACK - 1]); 40 41 return skb->ifindex * val * var; 42} 43 44SEC("tc") 45__success 46int global_func2(struct __sk_buff *skb) 47{ 48 return f0(1, skb) + f1(skb) + f2(2, skb) + f3(3, skb, 4); 49} 50