linuxdebug/tools/testing/selftests/bpf/progs/test_ksyms_weak.c

57 lines
1.3 KiB
C

// 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 */
/* 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;
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)
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);
return 0;
}
char _license[] SEC("license") = "GPL";