linux-stable/tools/testing/selftests/bpf/progs/btf_type_tag_percpu.c

67 lines
1.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2022 Google */
#include "vmlinux.h"
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
struct bpf_testmod_btf_type_tag_1 {
int a;
};
struct bpf_testmod_btf_type_tag_2 {
struct bpf_testmod_btf_type_tag_1 *p;
};
__u64 g;
SEC("fentry/bpf_testmod_test_btf_type_tag_percpu_1")
int BPF_PROG(test_percpu1, struct bpf_testmod_btf_type_tag_1 *arg)
{
g = arg->a;
return 0;
}
SEC("fentry/bpf_testmod_test_btf_type_tag_percpu_2")
int BPF_PROG(test_percpu2, struct bpf_testmod_btf_type_tag_2 *arg)
{
g = arg->p->a;
return 0;
}
/* trace_cgroup_mkdir(struct cgroup *cgrp, const char *path)
*
* struct cgroup_rstat_cpu {
* ...
* struct cgroup *updated_children;
* ...
* };
*
* struct cgroup {
* ...
* struct cgroup_rstat_cpu __percpu *rstat_cpu;
* ...
* };
*/
SEC("tp_btf/cgroup_mkdir")
int BPF_PROG(test_percpu_load, struct cgroup *cgrp, const char *path)
{
g = (__u64)cgrp->rstat_cpu->updated_children;
return 0;
}
SEC("tp_btf/cgroup_mkdir")
int BPF_PROG(test_percpu_helper, struct cgroup *cgrp, const char *path)
{
struct cgroup_rstat_cpu *rstat;
__u32 cpu;
cpu = bpf_get_smp_processor_id();
rstat = (struct cgroup_rstat_cpu *)bpf_per_cpu_ptr(cgrp->rstat_cpu, cpu);
if (rstat) {
/* READ_ONCE */
*(volatile int *)rstat;
}
return 0;
}