46 lines
903 B
C
46 lines
903 B
C
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// SPDX-License-Identifier: GPL-2.0-only
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/* Copyright (c) 2020 Facebook */
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#include <stddef.h>
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#include <linux/bpf.h>
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#include <bpf/bpf_helpers.h>
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#include "bpf_misc.h"
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#define MAX_STACK (512 - 3 * 32 + 8)
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static __attribute__ ((noinline))
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int f0(int var, struct __sk_buff *skb)
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{
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return skb->len;
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}
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__attribute__ ((noinline))
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int f1(struct __sk_buff *skb)
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{
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volatile char buf[MAX_STACK] = {};
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return f0(0, skb) + skb->len;
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}
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int f3(int, struct __sk_buff *skb, int);
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__attribute__ ((noinline))
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int f2(int val, struct __sk_buff *skb)
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{
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return f1(skb) + f3(val, skb, 1);
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}
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__attribute__ ((noinline))
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int f3(int val, struct __sk_buff *skb, int var)
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{
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volatile char buf[MAX_STACK] = {};
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return skb->ifindex * val * var;
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}
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SEC("tc")
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__failure __msg("combined stack size of 4 calls is 544")
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int global_func1(struct __sk_buff *skb)
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{
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return f0(1, skb) + f1(skb) + f2(2, skb) + f3(3, skb, 4);
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}
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