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// SPDX-License-Identifier: GPL-2.0
/*
* Test weak ksyms.
*
* Copyright (c) 2021 Google
*/
#include "vmlinux.h"
#include <bpf/bpf_helpers.h>
int out__existing_typed = -1;
__u64 out__existing_typeless = -1;
__u64 out__non_existent_typeless = -1;
__u64 out__non_existent_typed = -1;
/* existing weak symbols */
/* test existing weak symbols can be resolved. */
extern const struct rq runqueues __ksym __weak; /* typed */
extern const void bpf_prog_active __ksym __weak; /* typeless */
struct task_struct *bpf_task_acquire(struct task_struct *p) __ksym __weak;
void bpf_testmod_test_mod_kfunc(int i) __ksym __weak;
/* non-existent weak symbols. */
/* typeless symbols, default to zero. */
extern const void bpf_link_fops1 __ksym __weak;
/* typed symbols, default to zero. */
extern const int bpf_link_fops2 __ksym __weak;
void invalid_kfunc(void) __ksym __weak;
SEC("raw_tp/sys_enter")
int pass_handler(const void *ctx)
{
struct rq *rq;
/* tests existing symbols. */
rq = (struct rq *)bpf_per_cpu_ptr(&runqueues, 0);
if (rq && bpf_ksym_exists(&runqueues))
out__existing_typed = rq->cpu;
out__existing_typeless = (__u64)&bpf_prog_active;
/* tests non-existent symbols. */
out__non_existent_typeless = (__u64)&bpf_link_fops1;
/* tests non-existent symbols. */
out__non_existent_typed = (__u64)&bpf_link_fops2;
if (&bpf_link_fops2) /* can't happen */
out__non_existent_typed = (__u64)bpf_per_cpu_ptr(&bpf_link_fops2, 0);
if (!bpf_ksym_exists(bpf_task_acquire))
/* dead code won't be seen by the verifier */
bpf_task_acquire(0);
if (!bpf_ksym_exists(bpf_testmod_test_mod_kfunc))
/* dead code won't be seen by the verifier */
bpf_testmod_test_mod_kfunc(0);
if (bpf_ksym_exists(invalid_kfunc))
/* dead code won't be seen by the verifier */
invalid_kfunc();
return 0;
}
char _license[] SEC("license") = "GPL";
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