On Wed, Dec 27, 2023 at 6:01 PM Philo Lu <lulie@xxxxxxxxxxxxxxxxx> wrote:
>
> The operations of relay map create, update_elem, and output are tested.
> The test is borrowed from ringbuf tests, where 2 samples are written
> into the relay channel, and we get the samples by reading the files.
> Overwriting mode is also tested, where the size of relay buffer equals
> sample size and just the last sample can be seen.
>
> Signed-off-by: Philo Lu <lulie@xxxxxxxxxxxxxxxxx>
> ---
> tools/include/uapi/linux/bpf.h | 7 +
> tools/testing/selftests/bpf/Makefile | 2 +-
> tools/testing/selftests/bpf/config | 1 +
> .../selftests/bpf/prog_tests/relay_map.c | 197 ++++++++++++++++++
> .../selftests/bpf/progs/test_relay_map.c | 69 ++++++
> 5 files changed, 275 insertions(+), 1 deletion(-)
> create mode 100644 tools/testing/selftests/bpf/prog_tests/relay_map.c
> create mode 100644 tools/testing/selftests/bpf/progs/test_relay_map.c
>
> diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
> index 7f24d898efbb..1e545bfe701f 100644
> --- a/tools/include/uapi/linux/bpf.h
> +++ b/tools/include/uapi/linux/bpf.h
> @@ -951,6 +951,7 @@ enum bpf_map_type {
> BPF_MAP_TYPE_BLOOM_FILTER,
> BPF_MAP_TYPE_USER_RINGBUF,
> BPF_MAP_TYPE_CGRP_STORAGE,
> + BPF_MAP_TYPE_RELAY,
> };
>
> /* Note that tracing related programs such as
> @@ -1330,6 +1331,9 @@ enum {
>
> /* Get path from provided FD in BPF_OBJ_PIN/BPF_OBJ_GET commands */
> BPF_F_PATH_FD = (1U << 14),
> +
> +/* Enable overwrite for relay map */
> + BPF_F_OVERWRITE = (1U << 15),
> };
>
> /* Flags for BPF_PROG_QUERY. */
> @@ -1401,6 +1405,9 @@ union bpf_attr {
> * BPF_MAP_TYPE_BLOOM_FILTER - the lowest 4 bits indicate the
> * number of hash functions (if 0, the bloom filter will default
> * to using 5 hash functions).
> + *
> + * BPF_MAP_TYPE_RELAY - the lowest 32 bits indicate the number of
> + * relay subbufs (if 0, the number will be set to 8 by default).
> */
> __u64 map_extra;
> };
> diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
> index 617ae55c3bb5..8cebb3810d50 100644
> --- a/tools/testing/selftests/bpf/Makefile
> +++ b/tools/testing/selftests/bpf/Makefile
> @@ -427,7 +427,7 @@ LINKED_SKELS := test_static_linked.skel.h linked_funcs.skel.h \
> LSKELS := fentry_test.c fexit_test.c fexit_sleep.c atomics.c \
> trace_printk.c trace_vprintk.c map_ptr_kern.c \
> core_kern.c core_kern_overflow.c test_ringbuf.c \
> - test_ringbuf_map_key.c
> + test_ringbuf_map_key.c test_relay_map.c
>
> # Generate both light skeleton and libbpf skeleton for these
> LSKELS_EXTRA := test_ksyms_module.c test_ksyms_weak.c kfunc_call_test.c \
> diff --git a/tools/testing/selftests/bpf/config b/tools/testing/selftests/bpf/config
> index c125c441abc7..8de1adf587f0 100644
> --- a/tools/testing/selftests/bpf/config
> +++ b/tools/testing/selftests/bpf/config
> @@ -87,3 +87,4 @@ CONFIG_VSOCKETS=y
> CONFIG_VXLAN=y
> CONFIG_XDP_SOCKETS=y
> CONFIG_XFRM_INTERFACE=y
> +CONFIG_RELAY=y
> diff --git a/tools/testing/selftests/bpf/prog_tests/relay_map.c b/tools/testing/selftests/bpf/prog_tests/relay_map.c
> new file mode 100644
> index 000000000000..bd9c1e62ca78
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/prog_tests/relay_map.c
> @@ -0,0 +1,197 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#define _GNU_SOURCE
> +#include <linux/compiler.h>
> +#include <linux/bpf.h>
> +#include <sys/sysinfo.h>
> +#include <test_progs.h>
> +#include <sched.h>
> +
> +#include "test_relay_map.lskel.h"
> +
> +static int duration;
> +
> +/* file names in debugfs */
> +static const char dirname[] = "relay_map_selftest";
> +static const char mapname[] = "relay_map";
> +static const char mapname_ow[] = "relay_map_ow";
> +struct relay_sample {
> + int pid;
> + int seq;
> + long value;
> + char comm[16];
> +};
> +
> +static int sample_cnt;
> +static int overwrite;
> +
> +static void process_sample(struct relay_sample *s)
> +{
> + ++sample_cnt;
> +
> + switch (s->seq) {
> + case 0:
> + /* sample1 will not appear in overwrite mode */
> + CHECK(overwrite != 0, "overwrite_mode",
> + "sample1 appears in overwrite mode\n");
> + CHECK(s->value != 333, "sample1_value", "exp %ld, got %ld\n",
> + 333L, s->value);
> + break;
> + case 1:
> + CHECK(s->value != 777, "sample2_value", "exp %ld, got %ld\n",
> + 777L, s->value);
> + break;
> + default:
> + break;
> + }
> +}
> +
> +static int relaymap_read(const char *mapname)
> +{
> + int cpu = libbpf_num_possible_cpus();
> + char name[NAME_MAX];
> + struct relay_sample data;
> + int maxloop;
> + FILE *fp;
> +
> + for (int i = 0; i < cpu; ++i) {
> + sprintf(name, "/sys/kernel/debug/%s/%s%d", dirname, mapname, i);
> + fp = fopen(name, "r");
fclose() is missed.
> + if (CHECK(!fp, "fopen", "relay file open failed\n"))
> + return -1;
> +
> + maxloop = 0;
> + while (fread(&data, sizeof(data), 1, fp)) {
> + process_sample(&data);
> +
> + /* just 2 samples output */
> + if (++maxloop > 2)
> + return -1;
> + }
> + }
> + return 0;
> +}
> +
> +static struct test_relay_map_lskel *skel;
> +
> +static void trigger_samples(void)
> +{
> + skel->bss->dropped = 0;
> + skel->bss->total = 0;
> + skel->bss->seq = 0;
> +
> + /* trigger exactly two samples */
> + skel->bss->value = 333;
> + syscall(__NR_getpgid);
> + skel->bss->value = 777;
> + syscall(__NR_getpgid);
> +}
> +
> +static void relaymap_subtest(void)
> +{
> + int err, map_fd;
> +
> + skel = test_relay_map_lskel__open();
> + if (CHECK(!skel, "skel_open", "skeleton open failed\n"))
> + return;
> +
> + /* setup relay param */
> + skel->maps.relay_map.max_entries = 1024;
> +
> + err = test_relay_map_lskel__load(skel);
> + if (CHECK(err, "skel_load", "skeleton load failed\n"))
> + goto cleanup;
> +
> + /* only trigger BPF program for current process */
> + skel->bss->pid = getpid();
> +
> + /* turn off overwrite */
> + skel->bss->overwrite_enable = 0;
> + overwrite = skel->bss->overwrite_enable;
> +
> + err = test_relay_map_lskel__attach(skel);
> + if (CHECK(err, "skel_attach", "skeleton attachment failed: %d\n", err))
> + goto cleanup;
> +
> + /* before file setup - output failed */
> + trigger_samples();
> + CHECK(skel->bss->dropped != 2, "err_dropped", "exp %ld, got %ld\n",
> + 0L, skel->bss->dropped);
> + CHECK(skel->bss->total != 2, "err_total", "exp %ld, got %ld\n",
> + 2L, skel->bss->total);
> +
> + /* after file setup - output succ */
> + map_fd = skel->maps.relay_map.map_fd;
> + err = bpf_map_update_elem(map_fd, NULL, dirname, 0);
> + if (CHECK(err, "map_update", "map update failed: %d\n", err))
> + goto cleanup;
> + trigger_samples();
> + CHECK(skel->bss->dropped != 0, "err_dropped", "exp %ld, got %ld\n",
> + 0L, skel->bss->dropped);
> + CHECK(skel->bss->total != 2, "err_total", "exp %ld, got %ld\n",
> + 2L, skel->bss->total);
> +
> + sample_cnt = 0;
> + err = relaymap_read(mapname);
> + CHECK(sample_cnt != 2, "sample_cnt", "exp %d samples, got %d\n",
> + 2, sample_cnt);
> +
> + test_relay_map_lskel__detach(skel);
> +cleanup:
> + test_relay_map_lskel__destroy(skel);
> +}
> +
> +static void relaymap_overwrite_subtest(void)
> +{
> + int err, map_fd;
> +
> + skel = test_relay_map_lskel__open();
> + if (CHECK(!skel, "skel_open", "skeleton open failed\n"))
> + return;
> +
> + /* To test overwrite mode, we create subbuf of one-sample size */
> + skel->maps.relay_map_ow.max_entries = sizeof(struct relay_sample);
> +
> + err = test_relay_map_lskel__load(skel);
> + if (CHECK(err, "skel_load", "skeleton load failed\n"))
> + goto cleanup;
> +
> + /* only trigger BPF program for current process */
> + skel->bss->pid = getpid();
> +
> + /* turn on overwrite */
> + skel->bss->overwrite_enable = 1;
> + overwrite = skel->bss->overwrite_enable;
> +
> + err = test_relay_map_lskel__attach(skel);
> + if (CHECK(err, "skel_attach", "skeleton attachment failed: %d\n", err))
> + goto cleanup;
> +
> + map_fd = skel->maps.relay_map_ow.map_fd;
> + err = bpf_map_update_elem(map_fd, NULL, dirname, 0);
> + if (CHECK(err, "map_update", "map update failed: %d\n", err))
> + goto cleanup;
> + trigger_samples();
> + /* relay_write never fails whether overwriting or not */
> + CHECK(skel->bss->dropped != 0, "err_dropped", "exp %ld, got %ld\n",
> + 0L, skel->bss->dropped);
> + CHECK(skel->bss->total != 2, "err_total", "exp %ld, got %ld\n",
> + 2L, skel->bss->total);
> +
> + /* 2 samples are output, but only the last (val=777) could be seen */
> + sample_cnt = 0;
> + err = relaymap_read(mapname_ow);
> + CHECK(sample_cnt != 1, "sample_cnt", "exp %d samples, got %d\n",
> + 1, sample_cnt);
> +
> + test_relay_map_lskel__detach(skel);
> +cleanup:
> + test_relay_map_lskel__destroy(skel);
> +}
> +
> +void test_relaymap(void)
> +{
> + if (test__start_subtest("relaymap"))
> + relaymap_subtest();
> + if (test__start_subtest("relaymap_overwrite"))
> + relaymap_overwrite_subtest();
> +}
> diff --git a/tools/testing/selftests/bpf/progs/test_relay_map.c b/tools/testing/selftests/bpf/progs/test_relay_map.c
> new file mode 100644
> index 000000000000..1adf1be8e125
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/progs/test_relay_map.c
> @@ -0,0 +1,69 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#include <vmlinux.h>
> +#include <bpf/bpf_helpers.h>
> +#include "bpf_misc.h"
> +
> +char _license[] SEC("license") = "GPL";
> +
> +extern int bpf_relay_output(struct bpf_map *map, void *data,
> + __u64 data__sz, __u32 flags) __ksym;
> +
> +struct relay_sample {
> + int pid;
> + int seq;
> + long value;
> + char comm[16];
> +};
> +
> +struct {
> + __uint(type, BPF_MAP_TYPE_RELAY);
> + __uint(max_entries, 1024);
> +} relay_map SEC(".maps");
> +
> +struct {
> + __uint(type, BPF_MAP_TYPE_RELAY);
> + __uint(map_flags, BPF_F_OVERWRITE);
> + __uint(max_entries, 1024);
> + __uint(map_extra, 1);
> +} relay_map_ow SEC(".maps");
> +
> +/* inputs */
> +int pid = 0;
> +long value = 0;
> +int overwrite_enable = 0;
> +
> +/* outputs */
> +long total = 0;
> +long dropped = 0;
> +
> +/* inner state */
> +long seq = 0;
> +
> +SEC("fentry/" SYS_PREFIX "sys_getpgid")
> +int test_bpf_relaymap(void *ctx)
> +{
> + int cur_pid = bpf_get_current_pid_tgid() >> 32;
> + struct relay_sample sample;
> + int ret = 0;
> +
> + if (cur_pid != pid)
> + return 0;
> +
> + sample.pid = pid;
> + bpf_get_current_comm(sample.comm, sizeof(sample.comm));
> + sample.value = value;
> + sample.seq = seq++;
> + __sync_fetch_and_add(&total, 1);
> +
> + if (overwrite_enable)
> + ret = bpf_relay_output((struct bpf_map *)&relay_map_ow,
> + &sample, sizeof(sample), 0);
> + else
> + ret = bpf_relay_output((struct bpf_map *)&relay_map,
> + &sample, sizeof(sample), 0);
> +
> + if (ret)
> + __sync_fetch_and_add(&dropped, 1);
> +
> + return 0;
> +}
> --
> 2.32.0.3.g01195cf9f
>
--
Regards
Yafang
