1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (c) 2021 Facebook */ 3 4 #include "vmlinux.h" 5 #include <bpf/bpf_helpers.h> 6 7 #define X_0(x) 8 #define X_1(x) x X_0(x) 9 #define X_2(x) x X_1(x) 10 #define X_3(x) x X_2(x) 11 #define X_4(x) x X_3(x) 12 #define X_5(x) x X_4(x) 13 #define X_6(x) x X_5(x) 14 #define X_7(x) x X_6(x) 15 #define X_8(x) x X_7(x) 16 #define X_9(x) x X_8(x) 17 #define X_10(x) x X_9(x) 18 #define REPEAT_256(Y) X_2(X_10(X_10(Y))) X_5(X_10(Y)) X_6(Y) 19 20 extern const int bpf_testmod_ksym_percpu __ksym; 21 extern void bpf_testmod_test_mod_kfunc(int i) __ksym; 22 extern void bpf_testmod_invalid_mod_kfunc(void) __ksym __weak; 23 24 int out_bpf_testmod_ksym = 0; 25 const volatile int x = 0; 26 27 SEC("tc") 28 int load(struct __sk_buff *skb) 29 { 30 /* This will be kept by clang, but removed by verifier. Since it is 31 * marked as __weak, libbpf and gen_loader don't error out if BTF ID 32 * is not found for it, instead imm and off is set to 0 for it. 33 */ 34 if (x) 35 bpf_testmod_invalid_mod_kfunc(); 36 bpf_testmod_test_mod_kfunc(42); 37 out_bpf_testmod_ksym = *(int *)bpf_this_cpu_ptr(&bpf_testmod_ksym_percpu); 38 return 0; 39 } 40 41 SEC("tc") 42 int load_256(struct __sk_buff *skb) 43 { 44 /* this will fail if kfunc doesn't reuse its own btf fd index */ 45 REPEAT_256(bpf_testmod_test_mod_kfunc(42);); 46 bpf_testmod_test_mod_kfunc(42); 47 return 0; 48 } 49 50 char LICENSE[] SEC("license") = "GPL"; 51