linux/tools/testing/selftests/bpf/progs/epilogue_exit.c
Toke Høiland-Jørgensen d6212d82bf selftests/bpf: Consolidate kernel modules into common directory
The selftests build four kernel modules which use copy-pasted Makefile
targets. This is a bit messy, and doesn't scale so well when we add more
modules, so let's consolidate these rules into a single rule generated
for each module name, and move the module sources into a single
directory.

To avoid parallel builds of the different modules stepping on each
other's toes during the 'modpost' phase of the Kbuild 'make modules',
the module files should really be a grouped target. However, make only
added explicit support for grouped targets in version 4.3, which is
newer than the minimum version supported by the kernel. However, make
implicitly treats pattern matching rules with multiple targets as a
grouped target, so we can work around this by turning the rule into a
pattern matching target. We do this by replacing '.ko' with '%ko' in the
targets with subst().

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Viktor Malik <vmalik@redhat.com>
Link: https://lore.kernel.org/bpf/20241204-bpf-selftests-mod-compile-v5-1-b96231134a49@redhat.com
2024-12-06 10:44:10 -08:00

82 lines
1.9 KiB
C

// 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";
__success
/* save __u64 *ctx to stack */
__xlated("0: *(u64 *)(r10 -8) = r1")
/* main prog */
__xlated("1: r1 = *(u64 *)(r1 +0)")
__xlated("2: r2 = *(u64 *)(r1 +0)")
__xlated("3: r3 = 0")
__xlated("4: r4 = 1")
__xlated("5: if r2 == 0x0 goto pc+10")
__xlated("6: r0 = 0")
__xlated("7: *(u64 *)(r1 +0) = r3")
/* epilogue */
__xlated("8: r1 = *(u64 *)(r10 -8)")
__xlated("9: r1 = *(u64 *)(r1 +0)")
__xlated("10: r6 = *(u64 *)(r1 +0)")
__xlated("11: r6 += 10000")
__xlated("12: *(u64 *)(r1 +0) = r6")
__xlated("13: r0 = r6")
__xlated("14: r0 *= 2")
__xlated("15: exit")
/* 2nd part of the main prog after the first exit */
__xlated("16: *(u64 *)(r1 +0) = r4")
__xlated("17: r0 = 1")
/* Clear the r1 to ensure it does not have
* off-by-1 error and ensure it jumps back to the
* beginning of epilogue which initializes
* the r1 with the ctx ptr.
*/
__xlated("18: r1 = 0")
__xlated("19: gotol pc-12")
SEC("struct_ops/test_epilogue_exit")
__naked int test_epilogue_exit(void)
{
asm volatile (
"r1 = *(u64 *)(r1 +0);"
"r2 = *(u64 *)(r1 +0);"
"r3 = 0;"
"r4 = 1;"
"if r2 == 0 goto +3;"
"r0 = 0;"
"*(u64 *)(r1 + 0) = r3;"
"exit;"
"*(u64 *)(r1 + 0) = r4;"
"r0 = 1;"
"r1 = 0;"
"exit;"
::: __clobber_all);
}
SEC(".struct_ops.link")
struct bpf_testmod_st_ops epilogue_exit = {
.test_epilogue = (void *)test_epilogue_exit,
};
SEC("syscall")
__retval(20000)
int syscall_epilogue_exit0(void *ctx)
{
struct st_ops_args args = { .a = 1 };
return bpf_kfunc_st_ops_test_epilogue(&args);
}
SEC("syscall")
__retval(20002)
int syscall_epilogue_exit1(void *ctx)
{
struct st_ops_args args = {};
return bpf_kfunc_st_ops_test_epilogue(&args);
}