tools/testing/selftests/bpf/progs/pro_epilogue.c

Source file repositories/reference/linux-study-clean/tools/testing/selftests/bpf/progs/pro_epilogue.c

File Facts

System
Linux kernel
Corpus path
tools/testing/selftests/bpf/progs/pro_epilogue.c
Extension
.c
Size
3541 bytes
Lines
155
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: implementation source
Status
source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */

#include <vmlinux.h>
#include <bpf/bpf_tracing.h>
#include "bpf_misc.h"
#include "../test_kmods/bpf_testmod.h"
#include "../test_kmods/bpf_testmod_kfunc.h"

char _license[] SEC("license") = "GPL";

void __kfunc_btf_root(void)
{
	bpf_kfunc_st_ops_inc10(NULL);
}

static __noinline __used int subprog(struct st_ops_args *args)
{
	args->a += 1;
	return args->a;
}

__success
/* prologue */
__xlated("0: r6 = *(u64 *)(r1 +0)")
__xlated("1: r7 = *(u64 *)(r6 +0)")
__xlated("2: r7 += 1000")
__xlated("3: *(u64 *)(r6 +0) = r7")
/* main prog */
__xlated("4: r1 = *(u64 *)(r1 +0)")
__xlated("5: r6 = r1")
__xlated("6: call kernel-function")
__xlated("7: r1 = r6")
__xlated("8: call pc+1")
__xlated("9: exit")
SEC("struct_ops/test_prologue")
__naked int test_prologue(void)
{
	asm volatile (
	"r1 = *(u64 *)(r1 +0);"
	"r6 = r1;"
	"call %[bpf_kfunc_st_ops_inc10];"
	"r1 = r6;"
	"call subprog;"
	"exit;"
	:
	: __imm(bpf_kfunc_st_ops_inc10)
	: __clobber_all);
}

__success
/* save __u64 *ctx to stack */
__xlated("0: *(u64 *)(r10 -8) = r1")
/* main prog */
__xlated("1: r1 = *(u64 *)(r1 +0)")
__xlated("2: r6 = r1")
__xlated("3: call kernel-function")
__xlated("4: r1 = r6")
__xlated("5: call pc+")
/* epilogue */
__xlated("6: r1 = *(u64 *)(r10 -8)")
__xlated("7: r1 = *(u64 *)(r1 +0)")
__xlated("8: r6 = *(u64 *)(r1 +0)")
__xlated("9: r6 += 10000")
__xlated("10: *(u64 *)(r1 +0) = r6")
__xlated("11: r0 = r6")
__xlated("12: r0 *= 2")
__xlated("13: exit")
SEC("struct_ops/test_epilogue")
__naked int test_epilogue(void)
{
	asm volatile (
	"r1 = *(u64 *)(r1 +0);"
	"r6 = r1;"
	"call %[bpf_kfunc_st_ops_inc10];"
	"r1 = r6;"
	"call subprog;"
	"exit;"
	:
	: __imm(bpf_kfunc_st_ops_inc10)
	: __clobber_all);
}

__success
/* prologue */
__xlated("0: r6 = *(u64 *)(r1 +0)")
__xlated("1: r7 = *(u64 *)(r6 +0)")
__xlated("2: r7 += 1000")
__xlated("3: *(u64 *)(r6 +0) = r7")
/* save __u64 *ctx to stack */

Annotation

Implementation Notes