On Thu, Feb 13, 2025 at 8:20 AM Leon Hwang <leon.hwang@xxxxxxxxx> wrote:
>
> If the arch, like s390x, does not support percpu insn, this case won't
> test global percpu data by checking -EOPNOTSUPP after loading prog.
>
> The following APIs have been tested for global percpu data:
> 1. bpf_map__set_initial_value()
> 2. bpf_map__initial_value()
> 3. generated percpu struct pointer pointing to internal map's mmaped
> 4. bpf_map__lookup_elem() for global percpu data map
> 5. bpf_map__is_internal_percpu()
>
> At the same time, the case is also tested with 'bpftool gen skeleton -L'.
>
> 125 global_percpu_data_init:OK
> 126 global_percpu_data_lskel:OK
> Summary: 2/0 PASSED, 0 SKIPPED, 0 FAILED
>
> Signed-off-by: Leon Hwang <leon.hwang@xxxxxxxxx>
> ---
> tools/testing/selftests/bpf/Makefile | 2 +-
> .../bpf/prog_tests/global_data_init.c | 217 +++++++++++++++++-
> .../bpf/progs/test_global_percpu_data.c | 20 ++
> 3 files changed, 237 insertions(+), 2 deletions(-)
> create mode 100644 tools/testing/selftests/bpf/progs/test_global_percpu_data.c
>
> diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
> index 0d552bfcfe7da..7991de79d55c5 100644
> --- a/tools/testing/selftests/bpf/Makefile
> +++ b/tools/testing/selftests/bpf/Makefile
> @@ -503,7 +503,7 @@ LSKELS := fentry_test.c fexit_test.c fexit_sleep.c atomics.c \
>
> # Generate both light skeleton and libbpf skeleton for these
> LSKELS_EXTRA := test_ksyms_module.c test_ksyms_weak.c kfunc_call_test.c \
> - kfunc_call_test_subprog.c
> + kfunc_call_test_subprog.c test_global_percpu_data.c
> SKEL_BLACKLIST += $$(LSKELS)
>
> test_static_linked.skel.h-deps := test_static_linked1.bpf.o test_static_linked2.bpf.o
> diff --git a/tools/testing/selftests/bpf/prog_tests/global_data_init.c b/tools/testing/selftests/bpf/prog_tests/global_data_init.c
> index 8466332d7406f..5ace86a0eace7 100644
> --- a/tools/testing/selftests/bpf/prog_tests/global_data_init.c
> +++ b/tools/testing/selftests/bpf/prog_tests/global_data_init.c
> @@ -1,5 +1,8 @@
> // SPDX-License-Identifier: GPL-2.0
> #include <test_progs.h>
> +#include "bpf/libbpf_internal.h"
> +#include "test_global_percpu_data.skel.h"
> +#include "test_global_percpu_data.lskel.h"
>
> void test_global_data_init(void)
> {
> @@ -8,7 +11,7 @@ void test_global_data_init(void)
> __u8 *buff = NULL, *newval = NULL;
> struct bpf_object *obj;
> struct bpf_map *map;
> - __u32 duration = 0;
> + __u32 duration = 0;
> size_t sz;
>
> obj = bpf_object__open_file(file, NULL);
> @@ -60,3 +63,215 @@ void test_global_data_init(void)
> free(newval);
> bpf_object__close(obj);
> }
> +
> +void test_global_percpu_data_init(void)
> +{
> + struct test_global_percpu_data__percpu init_value, *init_data, *data, *percpu_data;
> + int key, prog_fd, err, num_cpus, num_online, comm_fd = -1, i;
> + struct test_global_percpu_data *skel = NULL;
> + __u64 args[2] = {0x1234ULL, 0x5678ULL};
> + size_t elem_sz, init_data_sz;
> + char buf[] = "new_name";
> + struct bpf_map *map;
> + bool *online;
> + LIBBPF_OPTS(bpf_test_run_opts, topts,
> + .ctx_in = args,
> + .ctx_size_in = sizeof(args),
> + .flags = BPF_F_TEST_RUN_ON_CPU,
> + );
> +
> + num_cpus = libbpf_num_possible_cpus();
> + if (!ASSERT_GT(num_cpus, 0, "libbpf_num_possible_cpus"))
> + return;
> +
> + err = parse_cpu_mask_file("/sys/devices/system/cpu/online",
> + &online, &num_online);
> + if (!ASSERT_OK(err, "parse_cpu_mask_file"))
> + return;
> +
> + elem_sz = sizeof(*percpu_data);
> + percpu_data = calloc(num_cpus, elem_sz);
> + if (!ASSERT_OK_PTR(percpu_data, "calloc percpu_data"))
> + goto out;
> +
> + skel = test_global_percpu_data__open();
> + if (!ASSERT_OK_PTR(skel, "test_global_percpu_data__open"))
> + goto out;
> + if (!ASSERT_OK_PTR(skel->percpu, "skel->percpu"))
> + goto out;
> +
> + ASSERT_EQ(skel->percpu->data, -1, "skel->percpu->data");
> + ASSERT_FALSE(skel->percpu->run, "skel->percpu->run");
> + ASSERT_EQ(skel->percpu->data2, 0, "skel->percpu->data2");
this will only check the value on cpu0, right?
Let's check it on all ?
> + map = skel->maps.percpu;
> + if (!ASSERT_EQ(bpf_map__type(map), BPF_MAP_TYPE_PERCPU_ARRAY, "bpf_map__type"))
> + goto out;
> + if (!ASSERT_TRUE(bpf_map__is_internal_percpu(map), "bpf_map__is_internal_percpu"))
> + goto out;
> +
> + init_value.data = 2;
> + init_value.run = false;
> + err = bpf_map__set_initial_value(map, &init_value, sizeof(init_value));
> + if (!ASSERT_OK(err, "bpf_map__set_initial_value"))
> + goto out;
> +
> + init_data = bpf_map__initial_value(map, &init_data_sz);
> + if (!ASSERT_OK_PTR(init_data, "bpf_map__initial_value"))
> + goto out;
> +
> + ASSERT_EQ(init_data->data, init_value.data, "initial_value data");
> + ASSERT_EQ(init_data->run, init_value.run, "initial_value run");
> + ASSERT_EQ(init_data_sz, sizeof(init_value), "initial_value size");
> + ASSERT_EQ((void *) init_data, (void *) skel->percpu, "skel->percpu eq init_data");
> + ASSERT_EQ(skel->percpu->data, init_value.data, "skel->percpu->data");
> + ASSERT_EQ(skel->percpu->run, init_value.run, "skel->percpu->run");
> +
> + err = test_global_percpu_data__load(skel);
> + if (err == -EOPNOTSUPP) {
> + test__skip();
> + goto out;
> + }
> + if (!ASSERT_OK(err, "test_global_percpu_data__load"))
> + goto out;
> +
> + ASSERT_NULL(skel->percpu, "NULL skel->percpu");
> +
> + err = test_global_percpu_data__attach(skel);
> + if (!ASSERT_OK(err, "test_global_percpu_data__attach"))
> + goto out;
> +
> + comm_fd = open("/proc/self/comm", O_WRONLY|O_TRUNC);
> + if (!ASSERT_GE(comm_fd, 0, "open /proc/self/comm"))
> + goto out;
> +
> + err = write(comm_fd, buf, sizeof(buf));
> + if (!ASSERT_GE(err, 0, "task rename"))
> + goto out;
> +
> + prog_fd = bpf_program__fd(skel->progs.update_percpu_data);
> +
> + /* run on every CPU */
> + for (i = 0; i < num_online; i++) {
> + if (!online[i])
> + continue;
> +
> + topts.cpu = i;
> + topts.retval = 0;
> + err = bpf_prog_test_run_opts(prog_fd, &topts);
> + ASSERT_OK(err, "bpf_prog_test_run_opts");
> + ASSERT_EQ(topts.retval, 0, "bpf_prog_test_run_opts retval");
> + }
> +
> + key = 0;
> + err = bpf_map__lookup_elem(map, &key, sizeof(key), percpu_data,
> + elem_sz * num_cpus, 0);
> + if (!ASSERT_OK(err, "bpf_map__lookup_elem"))
> + goto out;
> +
> + for (i = 0; i < num_online; i++) {
> + if (!online[i])
> + continue;
> +
> + data = percpu_data + i;
> + ASSERT_EQ(data->data, 1, "percpu_data->data");
> + ASSERT_TRUE(data->run, "percpu_data->run");
> + ASSERT_EQ(data->data2, 0xc0de, "percpu_data->data2");
> + }
> +
> +out:
> + close(comm_fd);
> + test_global_percpu_data__destroy(skel);
> + if (percpu_data)
> + free(percpu_data);
> + free(online);
> +}
> +
> +void test_global_percpu_data_lskel(void)
> +{
> + int key, prog_fd, map_fd, err, num_cpus, num_online, comm_fd = -1, i;
> + struct test_global_percpu_data__percpu *data, *percpu_data;
> + struct test_global_percpu_data_lskel *lskel = NULL;
> + __u64 args[2] = {0x1234ULL, 0x5678ULL};
> + char buf[] = "new_name";
> + bool *online;
> + LIBBPF_OPTS(bpf_test_run_opts, topts,
> + .ctx_in = args,
> + .ctx_size_in = sizeof(args),
> + .flags = BPF_F_TEST_RUN_ON_CPU,
> + );
> +
> + num_cpus = libbpf_num_possible_cpus();
> + if (!ASSERT_GT(num_cpus, 0, "libbpf_num_possible_cpus"))
> + return;
> +
> + err = parse_cpu_mask_file("/sys/devices/system/cpu/online",
> + &online, &num_online);
> + if (!ASSERT_OK(err, "parse_cpu_mask_file"))
> + return;
> +
> + percpu_data = calloc(num_cpus, sizeof(*percpu_data));
> + if (!ASSERT_OK_PTR(percpu_data, "calloc percpu_data"))
> + goto out;
> +
> + lskel = test_global_percpu_data_lskel__open();
> + if (!ASSERT_OK_PTR(lskel, "test_global_percpu_data_lskel__open"))
> + goto out;
> +
> + err = test_global_percpu_data_lskel__load(lskel);
> + if (err == -EOPNOTSUPP) {
> + test__skip();
> + goto out;
> + }
> + if (!ASSERT_OK(err, "test_global_percpu_data_lskel__load"))
> + goto out;
> +
> + err = test_global_percpu_data_lskel__attach(lskel);
> + if (!ASSERT_OK(err, "test_global_percpu_data_lskel__attach"))
> + goto out;
> +
> + comm_fd = open("/proc/self/comm", O_WRONLY|O_TRUNC);
> + if (!ASSERT_GE(comm_fd, 0, "open /proc/self/comm"))
> + goto out;
> +
> + err = write(comm_fd, buf, sizeof(buf));
> + if (!ASSERT_GE(err, 0, "task rename"))
> + goto out;
why this odd double run of bpf prog?
First via task_rename and then directly?
Only use bpf_prog_test_run_opts() and avoiding attaching to a tracepoint?
> +
> + prog_fd = lskel->progs.update_percpu_data.prog_fd;
> +
> + /* run on every CPU */
> + for (i = 0; i < num_online; i++) {
> + if (!online[i])
> + continue;
> +
> + topts.cpu = i;
> + topts.retval = 0;
> + err = bpf_prog_test_run_opts(prog_fd, &topts);
> + ASSERT_OK(err, "bpf_prog_test_run_opts");
> + ASSERT_EQ(topts.retval, 0, "bpf_prog_test_run_opts retval");
> + }
> +
> + key = 0;
> + map_fd = lskel->maps.percpu.map_fd;
> + err = bpf_map_lookup_elem(map_fd, &key, percpu_data);
> + if (!ASSERT_OK(err, "bpf_map_lookup_elem"))
> + goto out;
> +
> + for (i = 0; i < num_online; i++) {
> + if (!online[i])
> + continue;
> +
> + data = percpu_data + i;
> + ASSERT_EQ(data->data, 1, "percpu_data->data");
> + ASSERT_TRUE(data->run, "percpu_data->run");
> + ASSERT_EQ(data->data2, 0xc0de, "percpu_data->data2");
> + }
> +
> +out:
> + close(comm_fd);
> + test_global_percpu_data_lskel__destroy(lskel);
> + if (percpu_data)
> + free(percpu_data);
> + free(online);
> +}
> diff --git a/tools/testing/selftests/bpf/progs/test_global_percpu_data.c b/tools/testing/selftests/bpf/progs/test_global_percpu_data.c
> new file mode 100644
> index 0000000000000..ada292d3a164c
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/progs/test_global_percpu_data.c
> @@ -0,0 +1,20 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright Leon Hwang */
Are you sure you can do it in your country?
Often enough copyright belongs to the company you work for.
> +#include <linux/bpf.h>
> +#include <bpf/bpf_helpers.h>
> +
> +int data SEC(".percpu") = -1;
> +int run SEC(".percpu") = 0;
> +int data2 SEC(".percpu");
Pls add u8, array of ints and struct { .. } vars for completeness.
pw-bot: cr
