On Sun, Jan 10, 2021 at 8:18 PM Yonghong Song <yhs@xxxxxx> wrote:
>
>
>
> On 1/8/21 2:09 PM, Andrii Nakryiko wrote:
> > Add per-CPU variable to bpf_testmod.ko and use those from new selftest to
> > validate it works end-to-end.
> >
> > Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
>
> Ack with a nit below.
>
> Acked-by: Yonghong Song <yhs@xxxxxx>
>
> > ---
> > .../selftests/bpf/bpf_testmod/bpf_testmod.c | 3 ++
> > .../selftests/bpf/prog_tests/ksyms_module.c | 33 +++++++++++++++++++
> > .../selftests/bpf/progs/test_ksyms_module.c | 26 +++++++++++++++
> > 3 files changed, 62 insertions(+)
> > create mode 100644 tools/testing/selftests/bpf/prog_tests/ksyms_module.c
> > create mode 100644 tools/testing/selftests/bpf/progs/test_ksyms_module.c
> >
> > diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
> > index 2df19d73ca49..0b991e115d1f 100644
> > --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
> > +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
> > @@ -3,6 +3,7 @@
> > #include <linux/error-injection.h>
> > #include <linux/init.h>
> > #include <linux/module.h>
> > +#include <linux/percpu-defs.h>
> > #include <linux/sysfs.h>
> > #include <linux/tracepoint.h>
> > #include "bpf_testmod.h"
> > @@ -10,6 +11,8 @@
> > #define CREATE_TRACE_POINTS
> > #include "bpf_testmod-events.h"
> >
> > +DEFINE_PER_CPU(int, bpf_testmod_ksym_percpu) = 123;
> > +
> > noinline ssize_t
> > bpf_testmod_test_read(struct file *file, struct kobject *kobj,
> > struct bin_attribute *bin_attr,
> > diff --git a/tools/testing/selftests/bpf/prog_tests/ksyms_module.c b/tools/testing/selftests/bpf/prog_tests/ksyms_module.c
> > new file mode 100644
> > index 000000000000..7fa3d8b6ca30
> > --- /dev/null
> > +++ b/tools/testing/selftests/bpf/prog_tests/ksyms_module.c
> > @@ -0,0 +1,33 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/* Copyright (c) 2021 Facebook */
> > +
> > +#include <test_progs.h>
> > +#include <bpf/libbpf.h>
> > +#include <bpf/btf.h>
> > +#include "test_ksyms_module.skel.h"
> > +
> > +static int duration;
> > +
> > +void test_ksyms_module(void)
> > +{
> > + struct test_ksyms_module* skel;
> > + struct test_ksyms_module__bss *bss;
> > + int err;
> > +
> > + skel = test_ksyms_module__open_and_load();
> > + if (CHECK(!skel, "skel_open", "failed to open skeleton\n"))
> > + return;
> > + bss = skel->bss;
> > +
> > + err = test_ksyms_module__attach(skel);
> > + if (CHECK(err, "skel_attach", "skeleton attach failed: %d\n", err))
> > + goto cleanup;
> > +
> > + usleep(1);
>
> The above bss = skel->bss might be moved here for better readability.
> Or better, you can remove definition bss and just use skel->bss
> in below two ASSERT_EQs.
Sure, I'll just inline for such a short test.
>
> > + ASSERT_EQ(bss->triggered, true, "triggered");
> > + ASSERT_EQ(bss->out_mod_ksym_global, 123, "global_ksym_val");
> > +
> > +cleanup:
> > + test_ksyms_module__destroy(skel);
> > +}
> > diff --git a/tools/testing/selftests/bpf/progs/test_ksyms_module.c b/tools/testing/selftests/bpf/progs/test_ksyms_module.c
> > new file mode 100644
> > index 000000000000..d6a0b3086b90
> > --- /dev/null
> > +++ b/tools/testing/selftests/bpf/progs/test_ksyms_module.c
> > @@ -0,0 +1,26 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/* Copyright (c) 2021 Facebook */
> > +
> > +#include "vmlinux.h"
> > +
> > +#include <bpf/bpf_helpers.h>
> > +
> > +extern const int bpf_testmod_ksym_percpu __ksym;
> > +
> > +int out_mod_ksym_global = 0;
> > +bool triggered = false;
> > +
> > +SEC("raw_tp/sys_enter")
> > +int handler(const void *ctx)
> > +{
> > + int *val;
> > + __u32 cpu;
> > +
> > + val = (int *)bpf_this_cpu_ptr(&bpf_testmod_ksym_percpu);
> > + out_mod_ksym_global = *val;
> > + triggered = true;
> > +
> > + return 0;
> > +}
> > +
> > +char LICENSE[] SEC("license") = "GPL";
> >
