Re: [PATCH bpf-next 3/5] selftests/bpf: add selftest for BPF_PROG_TYPE_USER
On Sun, Aug 2, 2020 at 9:33 PM Song Liu wrote:
>
>
>
> > On Aug 2, 2020, at 6:43 PM, Andrii Nakryiko
> > wrote:
> >
> > On Sat, Aug 1, 2020 at 1:50 AM Song Liu wrote:
> >>
> >> This test checks the correctness of BPF_PROG_TYPE_USER program, including:
> >> running on the right cpu, passing in correct args, returning retval, and
> >> being able to call bpf_get_stack|stackid.
> >>
> >> Signed-off-by: Song Liu
> >> ---
> >> .../selftests/bpf/prog_tests/user_prog.c | 52 +
> >> tools/testing/selftests/bpf/progs/user_prog.c | 56 +++
> >> 2 files changed, 108 insertions(+)
> >> create mode 100644 tools/testing/selftests/bpf/prog_tests/user_prog.c
> >> create mode 100644 tools/testing/selftests/bpf/progs/user_prog.c
> >>
> >> diff --git a/tools/testing/selftests/bpf/prog_tests/user_prog.c
> >> b/tools/testing/selftests/bpf/prog_tests/user_prog.c
> >> new file mode 100644
> >> index 0..416707b3bff01
> >> --- /dev/null
> >> +++ b/tools/testing/selftests/bpf/prog_tests/user_prog.c
> >> @@ -0,0 +1,52 @@
> >> +// SPDX-License-Identifier: GPL-2.0
> >> +/* Copyright (c) 2020 Facebook */
> >> +#include
> >> +#include "user_prog.skel.h"
> >> +
> >> +static int duration;
> >> +
> >> +void test_user_prog(void)
> >> +{
> >> + struct bpf_user_prog_args args = {{0, 1, 2, 3, 4}};
> >> + struct bpf_prog_test_run_attr attr = {};
> >> + struct user_prog *skel;
> >> + int i, numcpu, ret;
> >> +
> >> + skel = user_prog__open_and_load();
> >> +
> >> + if (CHECK(!skel, "user_prog__open_and_load",
> >> + "skeleton open_and_laod failed\n"))
> >> + return;
> >> +
> >> + numcpu = libbpf_num_possible_cpus();
> >
> > nit: possible doesn't mean online right now, so it will fail on
> > offline or non-present CPUs
>
> Just found parse_cpu_mask_file(), will use it to fix this.
>
> [...]
>
> >> +
> >> +volatile int cpu_match = 1;
> >> +volatile __u64 sum = 1;
> >> +volatile int get_stack_success = 0;
> >> +volatile int get_stackid_success = 0;
> >> +volatile __u64 stacktrace[PERF_MAX_STACK_DEPTH];
> >
> > nit: no need for volatile for non-static variables
> >
> >> +
> >> +SEC("user")
> >> +int user_func(struct bpf_user_prog_ctx *ctx)
> >
> > If you put args in bpf_user_prog_ctx as a first field, you should be
> > able to re-use the BPF_PROG macro to access those arguments in a more
> > user-friendly way.
>
> I am not sure I am following here. Do you mean something like:
>
> struct bpf_user_prog_ctx {
> __u64 args[BPF_USER_PROG_MAX_ARGS];
> struct pt_regs *regs;
> };
>
> (swap args and regs)?
>
Yes, BPF_PROG assumes that context is a plain u64[5] array, so if you
put args at the beginning, it will work nicely with BPF_PROG.
> Thanks,
> Song
>
>
Re: [PATCH bpf-next 3/5] selftests/bpf: add selftest for BPF_PROG_TYPE_USER
> On Aug 2, 2020, at 6:43 PM, Andrii Nakryiko wrote:
>
> On Sat, Aug 1, 2020 at 1:50 AM Song Liu wrote:
>>
>> This test checks the correctness of BPF_PROG_TYPE_USER program, including:
>> running on the right cpu, passing in correct args, returning retval, and
>> being able to call bpf_get_stack|stackid.
>>
>> Signed-off-by: Song Liu
>> ---
>> .../selftests/bpf/prog_tests/user_prog.c | 52 +
>> tools/testing/selftests/bpf/progs/user_prog.c | 56 +++
>> 2 files changed, 108 insertions(+)
>> create mode 100644 tools/testing/selftests/bpf/prog_tests/user_prog.c
>> create mode 100644 tools/testing/selftests/bpf/progs/user_prog.c
>>
>> diff --git a/tools/testing/selftests/bpf/prog_tests/user_prog.c
>> b/tools/testing/selftests/bpf/prog_tests/user_prog.c
>> new file mode 100644
>> index 0..416707b3bff01
>> --- /dev/null
>> +++ b/tools/testing/selftests/bpf/prog_tests/user_prog.c
>> @@ -0,0 +1,52 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/* Copyright (c) 2020 Facebook */
>> +#include
>> +#include "user_prog.skel.h"
>> +
>> +static int duration;
>> +
>> +void test_user_prog(void)
>> +{
>> + struct bpf_user_prog_args args = {{0, 1, 2, 3, 4}};
>> + struct bpf_prog_test_run_attr attr = {};
>> + struct user_prog *skel;
>> + int i, numcpu, ret;
>> +
>> + skel = user_prog__open_and_load();
>> +
>> + if (CHECK(!skel, "user_prog__open_and_load",
>> + "skeleton open_and_laod failed\n"))
>> + return;
>> +
>> + numcpu = libbpf_num_possible_cpus();
>
> nit: possible doesn't mean online right now, so it will fail on
> offline or non-present CPUs
Just found parse_cpu_mask_file(), will use it to fix this.
[...]
>> +
>> +volatile int cpu_match = 1;
>> +volatile __u64 sum = 1;
>> +volatile int get_stack_success = 0;
>> +volatile int get_stackid_success = 0;
>> +volatile __u64 stacktrace[PERF_MAX_STACK_DEPTH];
>
> nit: no need for volatile for non-static variables
>
>> +
>> +SEC("user")
>> +int user_func(struct bpf_user_prog_ctx *ctx)
>
> If you put args in bpf_user_prog_ctx as a first field, you should be
> able to re-use the BPF_PROG macro to access those arguments in a more
> user-friendly way.
I am not sure I am following here. Do you mean something like:
struct bpf_user_prog_ctx {
__u64 args[BPF_USER_PROG_MAX_ARGS];
struct pt_regs *regs;
};
(swap args and regs)?
Thanks,
Song
Re: [PATCH bpf-next 3/5] selftests/bpf: add selftest for BPF_PROG_TYPE_USER
On Sat, Aug 1, 2020 at 1:50 AM Song Liu wrote:
>
> This test checks the correctness of BPF_PROG_TYPE_USER program, including:
> running on the right cpu, passing in correct args, returning retval, and
> being able to call bpf_get_stack|stackid.
>
> Signed-off-by: Song Liu
> ---
> .../selftests/bpf/prog_tests/user_prog.c | 52 +
> tools/testing/selftests/bpf/progs/user_prog.c | 56 +++
> 2 files changed, 108 insertions(+)
> create mode 100644 tools/testing/selftests/bpf/prog_tests/user_prog.c
> create mode 100644 tools/testing/selftests/bpf/progs/user_prog.c
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/user_prog.c
> b/tools/testing/selftests/bpf/prog_tests/user_prog.c
> new file mode 100644
> index 0..416707b3bff01
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/prog_tests/user_prog.c
> @@ -0,0 +1,52 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright (c) 2020 Facebook */
> +#include
> +#include "user_prog.skel.h"
> +
> +static int duration;
> +
> +void test_user_prog(void)
> +{
> + struct bpf_user_prog_args args = {{0, 1, 2, 3, 4}};
> + struct bpf_prog_test_run_attr attr = {};
> + struct user_prog *skel;
> + int i, numcpu, ret;
> +
> + skel = user_prog__open_and_load();
> +
> + if (CHECK(!skel, "user_prog__open_and_load",
> + "skeleton open_and_laod failed\n"))
> + return;
> +
> + numcpu = libbpf_num_possible_cpus();
nit: possible doesn't mean online right now, so it will fail on
offline or non-present CPUs
> +
> + attr.prog_fd = bpf_program__fd(skel->progs.user_func);
> + attr.data_size_in = sizeof(args);
> + attr.data_in =
> +
> + /* start from -1, so we test cpu_plus == 0 */
> + for (i = -1; i < numcpu; i++) {
> + args.args[0] = i + 1;
> + attr.cpu_plus = i + 1;
> + ret = bpf_prog_test_run_xattr();
> + CHECK(ret, "bpf_prog_test_run_xattr", "returns error\n");
> +
> + /* skip two tests for i == -1 */
> + if (i == -1)
> + continue;
> + CHECK(attr.retval != i + 2, "bpf_prog_test_run_xattr",
> + "doesn't get expected retval\n");
> + CHECK(skel->data->sum != 11 + i, "user_prog_args_test",
> + "sum of args doesn't match\n");
> + }
> +
> + CHECK(skel->data->cpu_match == 0, "cpu_match_test", "failed\n");
> + CHECK(skel->bss->get_stack_success != numcpu + 1,
> "test_bpf_get_stack",
> + "failed on %d cores\n", numcpu - skel->bss->get_stack_success);
> + CHECK(skel->bss->get_stackid_success != numcpu + 1,
> + "test_bpf_get_stackid",
> + "failed on %d cores\n",
> + numcpu + 1 - skel->bss->get_stackid_success);
> +
> + user_prog__destroy(skel);
> +}
> diff --git a/tools/testing/selftests/bpf/progs/user_prog.c
> b/tools/testing/selftests/bpf/progs/user_prog.c
> new file mode 100644
> index 0..cf320e97f107a
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/progs/user_prog.c
> @@ -0,0 +1,56 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright (c) 2020 Facebook */
> +#include "vmlinux.h"
> +#include
> +#include
> +
> +char _license[] SEC("license") = "GPL";
> +
> +#ifndef PERF_MAX_STACK_DEPTH
> +#define PERF_MAX_STACK_DEPTH 127
> +#endif
> +
> +typedef __u64 stack_trace_t[PERF_MAX_STACK_DEPTH];
> +
> +struct {
> + __uint(type, BPF_MAP_TYPE_STACK_TRACE);
> + __uint(max_entries, 16384);
> + __uint(key_size, sizeof(__u32));
> + __uint(value_size, sizeof(stack_trace_t));
> +} stackmap SEC(".maps");
> +
> +volatile int cpu_match = 1;
> +volatile __u64 sum = 1;
> +volatile int get_stack_success = 0;
> +volatile int get_stackid_success = 0;
> +volatile __u64 stacktrace[PERF_MAX_STACK_DEPTH];
nit: no need for volatile for non-static variables
> +
> +SEC("user")
> +int user_func(struct bpf_user_prog_ctx *ctx)
If you put args in bpf_user_prog_ctx as a first field, you should be
able to re-use the BPF_PROG macro to access those arguments in a more
user-friendly way.
> +{
> + int cpu = bpf_get_smp_processor_id();
> + __u32 key = cpu;
> + long stackid, err;
> +
> + /* check the program runs on the right cpu */
> + if (ctx->args[0] && ctx->args[0] != cpu + 1)
> + cpu_match = 0;
> +
> + /* check the sum of arguments are correct */
> + sum = ctx->args[0] + ctx->args[1] + ctx->args[2] +
> + ctx->args[3] + ctx->args[4];
> +
> + /* check bpf_get_stackid works */
> + stackid = bpf_get_stackid(ctx, , 0);
> + if (stackid >= 0)
> + get_stackid_success++;
> +
> + /* check bpf_get_stack works */
> + err = bpf_get_stack(ctx, (void *)stacktrace,
> + PERF_MAX_STACK_DEPTH * sizeof(__u64),
> +
[PATCH bpf-next 3/5] selftests/bpf: add selftest for BPF_PROG_TYPE_USER
This test checks the correctness of BPF_PROG_TYPE_USER program, including:
running on the right cpu, passing in correct args, returning retval, and
being able to call bpf_get_stack|stackid.
Signed-off-by: Song Liu
---
.../selftests/bpf/prog_tests/user_prog.c | 52 +
tools/testing/selftests/bpf/progs/user_prog.c | 56 +++
2 files changed, 108 insertions(+)
create mode 100644 tools/testing/selftests/bpf/prog_tests/user_prog.c
create mode 100644 tools/testing/selftests/bpf/progs/user_prog.c
diff --git a/tools/testing/selftests/bpf/prog_tests/user_prog.c
b/tools/testing/selftests/bpf/prog_tests/user_prog.c
new file mode 100644
index 0..416707b3bff01
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/user_prog.c
@@ -0,0 +1,52 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2020 Facebook */
+#include
+#include "user_prog.skel.h"
+
+static int duration;
+
+void test_user_prog(void)
+{
+ struct bpf_user_prog_args args = {{0, 1, 2, 3, 4}};
+ struct bpf_prog_test_run_attr attr = {};
+ struct user_prog *skel;
+ int i, numcpu, ret;
+
+ skel = user_prog__open_and_load();
+
+ if (CHECK(!skel, "user_prog__open_and_load",
+ "skeleton open_and_laod failed\n"))
+ return;
+
+ numcpu = libbpf_num_possible_cpus();
+
+ attr.prog_fd = bpf_program__fd(skel->progs.user_func);
+ attr.data_size_in = sizeof(args);
+ attr.data_in =
+
+ /* start from -1, so we test cpu_plus == 0 */
+ for (i = -1; i < numcpu; i++) {
+ args.args[0] = i + 1;
+ attr.cpu_plus = i + 1;
+ ret = bpf_prog_test_run_xattr();
+ CHECK(ret, "bpf_prog_test_run_xattr", "returns error\n");
+
+ /* skip two tests for i == -1 */
+ if (i == -1)
+ continue;
+ CHECK(attr.retval != i + 2, "bpf_prog_test_run_xattr",
+ "doesn't get expected retval\n");
+ CHECK(skel->data->sum != 11 + i, "user_prog_args_test",
+ "sum of args doesn't match\n");
+ }
+
+ CHECK(skel->data->cpu_match == 0, "cpu_match_test", "failed\n");
+ CHECK(skel->bss->get_stack_success != numcpu + 1, "test_bpf_get_stack",
+ "failed on %d cores\n", numcpu - skel->bss->get_stack_success);
+ CHECK(skel->bss->get_stackid_success != numcpu + 1,
+ "test_bpf_get_stackid",
+ "failed on %d cores\n",
+ numcpu + 1 - skel->bss->get_stackid_success);
+
+ user_prog__destroy(skel);
+}
diff --git a/tools/testing/selftests/bpf/progs/user_prog.c
b/tools/testing/selftests/bpf/progs/user_prog.c
new file mode 100644
index 0..cf320e97f107a
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/user_prog.c
@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2020 Facebook */
+#include "vmlinux.h"
+#include
+#include
+
+char _license[] SEC("license") = "GPL";
+
+#ifndef PERF_MAX_STACK_DEPTH
+#define PERF_MAX_STACK_DEPTH 127
+#endif
+
+typedef __u64 stack_trace_t[PERF_MAX_STACK_DEPTH];
+
+struct {
+ __uint(type, BPF_MAP_TYPE_STACK_TRACE);
+ __uint(max_entries, 16384);
+ __uint(key_size, sizeof(__u32));
+ __uint(value_size, sizeof(stack_trace_t));
+} stackmap SEC(".maps");
+
+volatile int cpu_match = 1;
+volatile __u64 sum = 1;
+volatile int get_stack_success = 0;
+volatile int get_stackid_success = 0;
+volatile __u64 stacktrace[PERF_MAX_STACK_DEPTH];
+
+SEC("user")
+int user_func(struct bpf_user_prog_ctx *ctx)
+{
+ int cpu = bpf_get_smp_processor_id();
+ __u32 key = cpu;
+ long stackid, err;
+
+ /* check the program runs on the right cpu */
+ if (ctx->args[0] && ctx->args[0] != cpu + 1)
+ cpu_match = 0;
+
+ /* check the sum of arguments are correct */
+ sum = ctx->args[0] + ctx->args[1] + ctx->args[2] +
+ ctx->args[3] + ctx->args[4];
+
+ /* check bpf_get_stackid works */
+ stackid = bpf_get_stackid(ctx, , 0);
+ if (stackid >= 0)
+ get_stackid_success++;
+
+ /* check bpf_get_stack works */
+ err = bpf_get_stack(ctx, (void *)stacktrace,
+ PERF_MAX_STACK_DEPTH * sizeof(__u64),
+ BPF_F_USER_STACK);
+ if (err >= 0)
+ get_stack_success++;
+
+ return cpu + 2;
+}
--
2.24.1
