1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Test weak ksyms. 4 * 5 * Copyright (c) 2021 Google 6 */ 7 8 #include "vmlinux.h" 9 10 #include <bpf/bpf_helpers.h> 11 12 int out__existing_typed = -1; 13 __u64 out__existing_typeless = -1; 14 15 __u64 out__non_existent_typeless = -1; 16 __u64 out__non_existent_typed = -1; 17 18 /* existing weak symbols */ 19 20 /* test existing weak symbols can be resolved. */ 21 extern const struct rq runqueues __ksym __weak; /* typed */ 22 extern const void bpf_prog_active __ksym __weak; /* typeless */ 23 24 25 /* non-existent weak symbols. */ 26 27 /* typeless symbols, default to zero. */ 28 extern const void bpf_link_fops1 __ksym __weak; 29 30 /* typed symbols, default to zero. */ 31 extern const int bpf_link_fops2 __ksym __weak; 32 33 SEC("raw_tp/sys_enter") 34 int pass_handler(const void *ctx) 35 { 36 struct rq *rq; 37 38 /* tests existing symbols. */ 39 rq = (struct rq *)bpf_per_cpu_ptr(&runqueues, 0); 40 if (rq) 41 out__existing_typed = rq->cpu; 42 out__existing_typeless = (__u64)&bpf_prog_active; 43 44 /* tests non-existent symbols. */ 45 out__non_existent_typeless = (__u64)&bpf_link_fops1; 46 47 /* tests non-existent symbols. */ 48 out__non_existent_typed = (__u64)&bpf_link_fops2; 49 50 if (&bpf_link_fops2) /* can't happen */ 51 out__non_existent_typed = (__u64)bpf_per_cpu_ptr(&bpf_link_fops2, 0); 52 53 return 0; 54 } 55 56 char _license[] SEC("license") = "GPL"; 57