Re: [PATCH v2 bpf-next 2/4] selftests/bpf: convert test_cgrp2_attach2 example into kselftest

From: Yonghong Song
Date: Thu May 23 2019 - 01:42:27 EST




On 5/22/19 4:20 PM, Roman Gushchin wrote:
> Convert test_cgrp2_attach2 example into a proper test_cgroup_attach
> kselftest. It's better because we do run kselftest on a constant
> basis, so there are better chances to spot a potential regression.
>
> Also make it slightly less verbose to conform kselftests output style.
>
> Output example:
> $ ./test_cgroup_attach
> #override:PASS
> #multi:PASS
> test_cgroup_attach:PASS
>
> Signed-off-by: Roman Gushchin <guro@xxxxxx>
Ack except the nit below.
Acked-by: Yonghong Song <yhs@xxxxxx>
> ---
> samples/bpf/Makefile | 2 -
> tools/testing/selftests/bpf/Makefile | 4 +-
> .../selftests/bpf/test_cgroup_attach.c | 48 ++++++++++++-------
> 3 files changed, 35 insertions(+), 19 deletions(-)
> rename samples/bpf/test_cgrp2_attach2.c => tools/testing/selftests/bpf/test_cgroup_attach.c (92%)
>
> diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
> index 4f0a1cdbfe7c..253e5a2856be 100644
> --- a/samples/bpf/Makefile
> +++ b/samples/bpf/Makefile
> @@ -26,7 +26,6 @@ hostprogs-y += map_perf_test
> hostprogs-y += test_overhead
> hostprogs-y += test_cgrp2_array_pin
> hostprogs-y += test_cgrp2_attach
> -hostprogs-y += test_cgrp2_attach2
> hostprogs-y += test_cgrp2_sock
> hostprogs-y += test_cgrp2_sock2
> hostprogs-y += xdp1
> @@ -81,7 +80,6 @@ map_perf_test-objs := bpf_load.o map_perf_test_user.o
> test_overhead-objs := bpf_load.o test_overhead_user.o
> test_cgrp2_array_pin-objs := test_cgrp2_array_pin.o
> test_cgrp2_attach-objs := test_cgrp2_attach.o
> -test_cgrp2_attach2-objs := test_cgrp2_attach2.o $(CGROUP_HELPERS)
> test_cgrp2_sock-objs := test_cgrp2_sock.o
> test_cgrp2_sock2-objs := bpf_load.o test_cgrp2_sock2.o
> xdp1-objs := xdp1_user.o
> diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
> index 66f2dca1dee1..e09f419f4d7e 100644
> --- a/tools/testing/selftests/bpf/Makefile
> +++ b/tools/testing/selftests/bpf/Makefile
> @@ -23,7 +23,8 @@ TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test
> test_align test_verifier_log test_dev_cgroup test_tcpbpf_user \
> test_sock test_btf test_sockmap test_lirc_mode2_user get_cgroup_id_user \
> test_socket_cookie test_cgroup_storage test_select_reuseport test_section_names \
> - test_netcnt test_tcpnotify_user test_sock_fields test_sysctl
> + test_netcnt test_tcpnotify_user test_sock_fields test_sysctl \
> + test_cgroup_attach
>
> BPF_OBJ_FILES = $(patsubst %.c,%.o, $(notdir $(wildcard progs/*.c)))
> TEST_GEN_FILES = $(BPF_OBJ_FILES)
> @@ -96,6 +97,7 @@ $(OUTPUT)/test_cgroup_storage: cgroup_helpers.c
> $(OUTPUT)/test_netcnt: cgroup_helpers.c
> $(OUTPUT)/test_sock_fields: cgroup_helpers.c
> $(OUTPUT)/test_sysctl: cgroup_helpers.c
> +$(OUTPUT)/test_cgroup_attach: cgroup_helpers.c
>
> .PHONY: force
>
> diff --git a/samples/bpf/test_cgrp2_attach2.c b/tools/testing/selftests/bpf/test_cgroup_attach.c
> similarity index 92%
> rename from samples/bpf/test_cgrp2_attach2.c
> rename to tools/testing/selftests/bpf/test_cgroup_attach.c
> index 0bb6507256b7..93d4fe295e7d 100644
> --- a/samples/bpf/test_cgrp2_attach2.c
> +++ b/tools/testing/selftests/bpf/test_cgroup_attach.c
> @@ -1,3 +1,5 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> /* eBPF example program:
> *
> * - Creates arraymap in kernel with 4 bytes keys and 8 byte values
> @@ -25,20 +27,27 @@
> #include <sys/resource.h>
> #include <sys/time.h>
> #include <unistd.h>
> +#include <linux/filter.h>
>
> #include <linux/bpf.h>
> #include <bpf/bpf.h>
>
> -#include "bpf_insn.h"
> +#include "bpf_util.h"
> #include "bpf_rlimit.h"
> #include "cgroup_helpers.h"
>
> #define FOO "/foo"
> #define BAR "/foo/bar/"
> -#define PING_CMD "ping -c1 -w1 127.0.0.1 > /dev/null"
> +#define PING_CMD "ping -q -c1 -w1 127.0.0.1 > /dev/null"
>
> char bpf_log_buf[BPF_LOG_BUF_SIZE];
>
> +#ifdef DEBUG
> +#define debug(args...) printf(args)
> +#else
> +#define debug(args...)
> +#endif
> +
> static int prog_load(int verdict)
> {
> int ret;
> @@ -89,7 +98,7 @@ static int test_foo_bar(void)
> goto err;
> }
>
> - printf("Attached DROP prog. This ping in cgroup /foo should fail...\n");
> + debug("Attached DROP prog. This ping in cgroup /foo should fail...\n");
> assert(system(PING_CMD) != 0);
>
> /* Create cgroup /foo/bar, get fd, and join it */
> @@ -100,7 +109,7 @@ static int test_foo_bar(void)
> if (join_cgroup(BAR))
> goto err;
>
> - printf("Attached DROP prog. This ping in cgroup /foo/bar should fail...\n");
> + debug("Attached DROP prog. This ping in cgroup /foo/bar should fail...\n");
> assert(system(PING_CMD) != 0);
>
> if (bpf_prog_attach(allow_prog, bar, BPF_CGROUP_INET_EGRESS,
> @@ -109,7 +118,7 @@ static int test_foo_bar(void)
> goto err;
> }
>
> - printf("Attached PASS prog. This ping in cgroup /foo/bar should pass...\n");
> + debug("Attached PASS prog. This ping in cgroup /foo/bar should pass...\n");
> assert(system(PING_CMD) == 0);
>
> if (bpf_prog_detach(bar, BPF_CGROUP_INET_EGRESS)) {
> @@ -117,7 +126,7 @@ static int test_foo_bar(void)
> goto err;
> }
>
> - printf("Detached PASS from /foo/bar while DROP is attached to /foo.\n"
> + debug("Detached PASS from /foo/bar while DROP is attached to /foo.\n"
> "This ping in cgroup /foo/bar should fail...\n");
> assert(system(PING_CMD) != 0);
>
> @@ -132,7 +141,7 @@ static int test_foo_bar(void)
> goto err;
> }
>
> - printf("Attached PASS from /foo/bar and detached DROP from /foo.\n"
> + debug("Attached PASS from /foo/bar and detached DROP from /foo.\n"
> "This ping in cgroup /foo/bar should pass...\n");
> assert(system(PING_CMD) == 0);
>
> @@ -199,9 +208,9 @@ static int test_foo_bar(void)
> close(bar);
> cleanup_cgroup_environment();
> if (!rc)
> - printf("### override:PASS\n");
> + printf("#override:PASS\n");
> else
> - printf("### override:FAIL\n");
> + printf("#override:FAIL\n");
> return rc;
> }
>
> @@ -441,19 +450,26 @@ static int test_multiprog(void)
> close(cg5);
> cleanup_cgroup_environment();
> if (!rc)
> - printf("### multi:PASS\n");
> + printf("#multi:PASS\n");
> else
> - printf("### multi:FAIL\n");
> + printf("#multi:FAIL\n");
> return rc;
> }
>
> int main(int argc, char **argv)

argc and argv are not used.

currently, the debug output is controlled by macro DEBUG.
you could enable debug output with command line option.
But I am okay with the current mechanism as well.

> {
> - int rc = 0;
> + int (*tests[])(void) = {test_foo_bar, test_multiprog};
> + int errors = 0;
> + int i;
>
> - rc = test_foo_bar();
> - if (rc)
> - return rc;
> + for (i = 0; i < ARRAY_SIZE(tests); i++)
> + if (tests[i]())
> + errors++;
> +
> + if (errors)
> + printf("test_cgroup_attach:FAIL\n");
> + else
> + printf("test_cgroup_attach:PASS\n");
>
> - return test_multiprog();
> + return errors ? EXIT_FAILURE : EXIT_SUCCESS;
> }
>