[PATCH bpf-next 0/7] Auto-guess program type on bpf_object__open

[PATCH bpf-next 0/7] Auto-guess program type on bpf_object__open

[Andrii Nakryiko]

This patch set's main goal is to teach bpf_object__open() (and its variants)
to automatically derive BPF program type/expected attach type from section
names, similarly to how bpf_prog_load() was doing it. This significantly
improves user experience by eliminating yet another
obvious-only-in-the-hindsight surprise, when using libbpf APIs.

There are a bunch of auxiliary clean-ups and improvements. E.g.,
bpf_program__get_type() and bpf_program__get_expected_attach_type() are added
for completeness and symmetry with corresponding setter APIs. Some clean up
and fixes in selftests/bpf are done as well.

Andrii Nakryiko (7):
  tools: sync if_link.h
  libbpf: add bpf_program__get_{type, expected_attach_type) APIs
  libbpf: add uprobe/uretprobe and tp/raw_tp section suffixes
  libbpf: teach bpf_object__open to guess program types
  selftests/bpf: make a copy of subtest name
  selftests/bpf: make reference_tracking test use subtests
  selftest/bpf: get rid of a bunch of explicit BPF program type setting

 tools/include/uapi/linux/if_link.h            |  2 +
 tools/lib/bpf/libbpf.c                        | 80 ++++++++++++-------
 tools/lib/bpf/libbpf.h                        |  5 ++
 tools/lib/bpf/libbpf.map                      |  2 +
 .../selftests/bpf/prog_tests/attach_probe.c   |  5 --
 .../selftests/bpf/prog_tests/core_reloc.c     |  1 -
 .../selftests/bpf/prog_tests/rdonly_maps.c    |  4 -
 .../bpf/prog_tests/reference_tracking.c       |  3 +-
 .../selftests/bpf/progs/test_sk_lookup_kern.c | 18 ++---
 tools/testing/selftests/bpf/test_maps.c       |  4 -
 tools/testing/selftests/bpf/test_progs.c      | 17 ++--
 11 files changed, 83 insertions(+), 58 deletions(-)

-- 
2.17.1

[PATCH bpf-next 1/7] tools: sync if_link.h

[Andrii Nakryiko]

Sync if_link.h into tools/ and get rid of annoying libbpf Makefile warning.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
---
 tools/include/uapi/linux/if_link.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tools/include/uapi/linux/if_link.h b/tools/include/uapi/linux/if_link.h
index 4a8c02cafa9a..8aec8769d944 100644
--- a/tools/include/uapi/linux/if_link.h
+++ b/tools/include/uapi/linux/if_link.h
@@ -167,6 +167,8 @@ enum {
 	IFLA_NEW_IFINDEX,
 	IFLA_MIN_MTU,
 	IFLA_MAX_MTU,
+	IFLA_PROP_LIST,
+	IFLA_ALT_IFNAME, /* Alternative ifname */
 	__IFLA_MAX
 };
 
-- 
2.17.1

[PATCH bpf-next 2/7] libbpf: add bpf_program__get_{type, expected_attach_type) APIs

[Andrii Nakryiko]

There are bpf_program__set_type() and
bpf_program__set_expected_attach_type(), but no corresponding getters,
which seems rather incomplete. Fix this.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
---
 tools/lib/bpf/libbpf.c   | 11 +++++++++++
 tools/lib/bpf/libbpf.h   |  5 +++++
 tools/lib/bpf/libbpf.map |  2 ++
 3 files changed, 18 insertions(+)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index cccfd9355134..39163e68dc1e 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -4468,6 +4468,11 @@ int bpf_program__nth_fd(const struct bpf_program *prog, int n)
 	return fd;
 }
 
+enum bpf_prog_type bpf_program__get_type(struct bpf_program *prog)
+{
+	return prog->type;
+}
+
 void bpf_program__set_type(struct bpf_program *prog, enum bpf_prog_type type)
 {
 	prog->type = type;
@@ -4502,6 +4507,12 @@ BPF_PROG_TYPE_FNS(raw_tracepoint, BPF_PROG_TYPE_RAW_TRACEPOINT);
 BPF_PROG_TYPE_FNS(xdp, BPF_PROG_TYPE_XDP);
 BPF_PROG_TYPE_FNS(perf_event, BPF_PROG_TYPE_PERF_EVENT);
 
+enum bpf_attach_type
+bpf_program__get_expected_attach_type(struct bpf_program *prog)
+{
+	return prog->expected_attach_type;
+}
+
 void bpf_program__set_expected_attach_type(struct bpf_program *prog,
 					   enum bpf_attach_type type)
 {
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index 53ce212764e0..0fdf086beba7 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -302,8 +302,13 @@ LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog);
 LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog);
 LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog);
 LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog);
+
+LIBBPF_API enum bpf_prog_type bpf_program__get_type(struct bpf_program *prog);
 LIBBPF_API void bpf_program__set_type(struct bpf_program *prog,
 				      enum bpf_prog_type type);
+
+LIBBPF_API enum bpf_attach_type
+bpf_program__get_expected_attach_type(struct bpf_program *prog);
 LIBBPF_API void
 bpf_program__set_expected_attach_type(struct bpf_program *prog,
 				      enum bpf_attach_type type);
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 4d241fd92dd4..d1473ea4d7a5 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -195,4 +195,6 @@ LIBBPF_0.0.6 {
 	global:
 		bpf_object__open_file;
 		bpf_object__open_mem;
+		bpf_program__get_expected_attach_type;
+		bpf_program__get_type;
 } LIBBPF_0.0.5;
-- 
2.17.1

[PATCH bpf-next 3/7] libbpf: add uprobe/uretprobe and tp/raw_tp section suffixes

[Andrii Nakryiko]

Map uprobe/uretprobe into KPROBE program type. tp/raw_tp are just an
alias for more verbose tracepoint/raw_tracepoint, respectively.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
---
 tools/lib/bpf/libbpf.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 39163e68dc1e..bf0c94fe74ca 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -4552,11 +4552,15 @@ static const struct {
 } section_names[] = {
 	BPF_PROG_SEC("socket",			BPF_PROG_TYPE_SOCKET_FILTER),
 	BPF_PROG_SEC("kprobe/",			BPF_PROG_TYPE_KPROBE),
+	BPF_PROG_SEC("uprobe/",			BPF_PROG_TYPE_KPROBE),
 	BPF_PROG_SEC("kretprobe/",		BPF_PROG_TYPE_KPROBE),
+	BPF_PROG_SEC("uretprobe/",		BPF_PROG_TYPE_KPROBE),
 	BPF_PROG_SEC("classifier",		BPF_PROG_TYPE_SCHED_CLS),
 	BPF_PROG_SEC("action",			BPF_PROG_TYPE_SCHED_ACT),
 	BPF_PROG_SEC("tracepoint/",		BPF_PROG_TYPE_TRACEPOINT),
+	BPF_PROG_SEC("tp/",			BPF_PROG_TYPE_TRACEPOINT),
 	BPF_PROG_SEC("raw_tracepoint/",		BPF_PROG_TYPE_RAW_TRACEPOINT),
+	BPF_PROG_SEC("raw_tp/",			BPF_PROG_TYPE_RAW_TRACEPOINT),
 	BPF_PROG_BTF("tp_btf/",			BPF_PROG_TYPE_RAW_TRACEPOINT),
 	BPF_PROG_SEC("xdp",			BPF_PROG_TYPE_XDP),
 	BPF_PROG_SEC("perf_event",		BPF_PROG_TYPE_PERF_EVENT),
-- 
2.17.1

[PATCH bpf-next 4/7] libbpf: teach bpf_object__open to guess program types

[Andrii Nakryiko]

Teach bpf_object__open how to guess program type and expected attach
type from section names, similar to what bpf_prog_load() does. This
seems like a really useful features and an oversight to not have this
done during bpf_object_open(). To preserver backwards compatible
behavior of bpf_prog_load(), its attr->prog_type is treated as an
override of bpf_object__open() decisions, if attr->prog_type is not
UNSPECIFIED.

There is a slight difference in behavior for bpf_prog_load().
Previously, if bpf_prog_load() was loading BPF object with more than one
program, first program's guessed program type and expected attach type
would determine corresponding attributes of all the subsequent program
types, even if their sections names suggest otherwise. That seems like
a rather dubious behavior and with this change it will behave more
sanely: each program's type is determined individually, unless they are
forced to uniformity through attr->prog_type.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
---
 tools/lib/bpf/libbpf.c | 65 +++++++++++++++++++++++-------------------
 1 file changed, 36 insertions(+), 29 deletions(-)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index bf0c94fe74ca..51c867c85bf4 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -3616,6 +3616,7 @@ static struct bpf_object *
 __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz,
 		   struct bpf_object_open_opts *opts)
 {
+	struct bpf_program *prog;
 	struct bpf_object *obj;
 	const char *obj_name;
 	char tmp_name[64];
@@ -3655,8 +3656,24 @@ __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz,
 	CHECK_ERR(bpf_object__probe_caps(obj), err, out);
 	CHECK_ERR(bpf_object__elf_collect(obj, relaxed_maps), err, out);
 	CHECK_ERR(bpf_object__collect_reloc(obj), err, out);
-
 	bpf_object__elf_finish(obj);
+
+	bpf_object__for_each_program(prog, obj) {
+		enum bpf_prog_type prog_type;
+		enum bpf_attach_type attach_type;
+
+		err = libbpf_prog_type_by_name(prog->section_name, &prog_type,
+					       &attach_type);
+		if (err == -ESRCH)
+			/* couldn't guess, but user might manually specify */
+			continue;
+		if (err)
+			goto out;
+
+		bpf_program__set_type(prog, prog_type);
+		bpf_program__set_expected_attach_type(prog, attach_type);
+	}
+
 	return obj;
 out:
 	bpf_object__close(obj);
@@ -4696,7 +4713,7 @@ int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
 		free(type_names);
 	}
 
-	return -EINVAL;
+	return -ESRCH;
 }
 
 int libbpf_attach_type_by_name(const char *name,
@@ -4726,15 +4743,6 @@ int libbpf_attach_type_by_name(const char *name,
 	return -EINVAL;
 }
 
-static int
-bpf_program__identify_section(struct bpf_program *prog,
-			      enum bpf_prog_type *prog_type,
-			      enum bpf_attach_type *expected_attach_type)
-{
-	return libbpf_prog_type_by_name(prog->section_name, prog_type,
-					expected_attach_type);
-}
-
 int bpf_map__fd(const struct bpf_map *map)
 {
 	return map ? map->fd : -EINVAL;
@@ -4902,8 +4910,6 @@ int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
 {
 	struct bpf_object_open_attr open_attr = {};
 	struct bpf_program *prog, *first_prog = NULL;
-	enum bpf_attach_type expected_attach_type;
-	enum bpf_prog_type prog_type;
 	struct bpf_object *obj;
 	struct bpf_map *map;
 	int err;
@@ -4921,26 +4927,27 @@ int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
 		return -ENOENT;
 
 	bpf_object__for_each_program(prog, obj) {
+		enum bpf_attach_type attach_type = attr->expected_attach_type;
 		/*
-		 * If type is not specified, try to guess it based on
-		 * section name.
+		 * to preserve backwards compatibility, bpf_prog_load treats
+		 * attr->prog_type, if specified, as an override to whatever
+		 * bpf_object__open guessed
 		 */
-		prog_type = attr->prog_type;
-		prog->prog_ifindex = attr->ifindex;
-		expected_attach_type = attr->expected_attach_type;
-		if (prog_type == BPF_PROG_TYPE_UNSPEC) {
-			err = bpf_program__identify_section(prog, &prog_type,
-							    &expected_attach_type);
-			if (err < 0) {
-				bpf_object__close(obj);
-				return -EINVAL;
-			}
+		if (attr->prog_type != BPF_PROG_TYPE_UNSPEC) {
+			bpf_program__set_type(prog, attr->prog_type);
+			bpf_program__set_expected_attach_type(prog,
+							      attach_type);
+		}
+		if (bpf_program__get_type(prog) == BPF_PROG_TYPE_UNSPEC) {
+			/*
+			 * we haven't guessed from section name and user
+			 * didn't provide a fallback type, too bad...
+			 */
+			bpf_object__close(obj);
+			return -EINVAL;
 		}
 
-		bpf_program__set_type(prog, prog_type);
-		bpf_program__set_expected_attach_type(prog,
-						      expected_attach_type);
-
+		prog->prog_ifindex = attr->ifindex;
 		prog->log_level = attr->log_level;
 		prog->prog_flags = attr->prog_flags;
 		if (!first_prog)
-- 
2.17.1

Re: [libbpf] 651b775f02: kernel_selftests.bpf.test_section_names.fail

[Andrii Nakryiko]

On Tue, Oct 22, 2019 at 9:25 PM kernel test robot <rong.a.chen@intel.com> wrote:
>
> FYI, we noticed the following commit (built with gcc-7):
>
> commit: 651b775f027f9758740d748cc08c5a0661f13bb7 ("[PATCH bpf-next 4/7] libbpf: teach bpf_object__open to guess program types")
> url: https://github.com/0day-ci/linux/commits/Andrii-Nakryiko/Auto-guess-program-type-on-bpf_object__open/20191021-214022
> base: https://git.kernel.org/cgit/linux/kernel/git/bpf/bpf-next.git master
>
> in testcase: kernel_selftests
> with following parameters:
>
>         group: kselftests-00
>
> test-description: The kernel contains a set of "self tests" under the tools/testing/selftests/ directory. These are intended to be small unit tests to exercise individual code paths in the kernel.
> test-url: https://www.kernel.org/doc/Documentation/kselftest.txt
>
>
> on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 8G
>
> caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):
>
>
>
>
> If you fix the issue, kindly add following tag
> Reported-by: kernel test robot <rong.a.chen@intel.com>

Thanks, fixed in https://patchwork.ozlabs.org/patch/1181840/

>
>
> # selftests: bpf: test_section_names
> # libbpf: failed to guess program type based on ELF section name 'InvAliD'
> # libbpf: supported section(type) names are: socket kprobe/ uprobe/ kretprobe/ uretprobe/ classifier action tracepoint/ tp/ raw_tracepoint/ raw_tp/ tp_btf/ xdp perf_event lwt_in lwt_out lwt_xmit lwt_seg6local cgroup_skb/ingress cgroup_skb/egress cgroup/skb cgroup/sock cgroup/post_bind4 cgroup/post_bind6 cgroup/dev sockops sk_skb/stream_parser sk_skb/stream_verdict sk_skb sk_msg lirc_mode2 flow_dissector cgroup/bind4 cgroup/bind6 cgroup/connect4 cgroup/connect6 cgroup/sendmsg4 cgroup/sendmsg6 cgroup/recvmsg4 cgroup/recvmsg6 cgroup/sysctl cgroup/getsockopt cgroup/setsockopt
> # test_section_names: prog: unexpected rc=-3 for InvAliD
> # libbpf: failed to guess program type based on ELF section name 'cgroup'
> # libbpf: supported section(type) names are: socket kprobe/ uprobe/ kretprobe/ uretprobe/ classifier action tracepoint/ tp/ raw_tracepoint/ raw_tp/ tp_btf/ xdp perf_event lwt_in lwt_out lwt_xmit lwt_seg6local cgroup_skb/ingress cgroup_skb/egress cgroup/skb cgroup/sock cgroup/post_bind4 cgroup/post_bind6 cgroup/dev sockops sk_skb/stream_parser sk_skb/stream_verdict sk_skb sk_msg lirc_mode2 flow_dissector cgroup/bind4 cgroup/bind6 cgroup/connect4 cgroup/connect6 cgroup/sendmsg4 cgroup/sendmsg6 cgroup/recvmsg4 cgroup/recvmsg6 cgroup/sysctl cgroup/getsockopt cgroup/setsockopt
> # test_section_names: prog: unexpected rc=-3 for cgroup
> # Summary: 38 PASSED, 2 FAILED
> not ok 18 selftests: bpf: test_section_names
>
>
> To reproduce:
>
>         # build kernel
>         cd linux
>         cp config-5.4.0-rc1-00593-g651b775f027f9 .config
>         make HOSTCC=gcc-7 CC=gcc-7 ARCH=x86_64 olddefconfig prepare modules_prepare bzImage
>
>         git clone https://github.com/intel/lkp-tests.git
>         cd lkp-tests
>         bin/lkp qemu -k <bzImage> job-script # job-script is attached in this email
>
>
>
> Thanks,
> Rong Chen
>

[PATCH bpf-next 5/7] selftests/bpf: make a copy of subtest name

[Andrii Nakryiko]

test_progs never created a copy of subtest name, rather just stored
pointer to whatever string test provided. This is bad as that string
might be freed or modified by the end of subtest. Fix this by creating
a copy of given subtest name when subtest starts.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
---
 tools/testing/selftests/bpf/test_progs.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c
index c7e52f4194e2..a05a807840c0 100644
--- a/tools/testing/selftests/bpf/test_progs.c
+++ b/tools/testing/selftests/bpf/test_progs.c
@@ -20,7 +20,7 @@ struct prog_test_def {
 	bool tested;
 	bool need_cgroup_cleanup;
 
-	const char *subtest_name;
+	char *subtest_name;
 	int subtest_num;
 
 	/* store counts before subtest started */
@@ -81,16 +81,17 @@ void test__end_subtest()
 	fprintf(env.stdout, "#%d/%d %s:%s\n",
 	       test->test_num, test->subtest_num,
 	       test->subtest_name, sub_error_cnt ? "FAIL" : "OK");
+
+	free(test->subtest_name);
+	test->subtest_name = NULL;
 }
 
 bool test__start_subtest(const char *name)
 {
 	struct prog_test_def *test = env.test;
 
-	if (test->subtest_name) {
+	if (test->subtest_name)
 		test__end_subtest();
-		test->subtest_name = NULL;
-	}
 
 	test->subtest_num++;
 
@@ -104,7 +105,13 @@ bool test__start_subtest(const char *name)
 	if (!should_run(&env.subtest_selector, test->subtest_num, name))
 		return false;
 
-	test->subtest_name = name;
+	test->subtest_name = strdup(name);
+	if (!test->subtest_name) {
+		fprintf(env.stderr,
+			"Subtest #%d: failed to copy subtest name!\n",
+			test->subtest_num);
+		return false;
+	}
 	env.test->old_error_cnt = env.test->error_cnt;
 
 	return true;
-- 
2.17.1

[PATCH bpf-next 6/7] selftests/bpf: make reference_tracking test use subtests

[Andrii Nakryiko]

reference_tracking is actually a set of 9 sub-tests. Make it explicitly so.

Also, add explicit "classifier/" prefix to BPF program section names to
let libbpf correctly guess program type. Thus, also remove explicit
bpf_prog__set_type() call.

Cc: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
---
 .../bpf/prog_tests/reference_tracking.c        |  3 ++-
 .../selftests/bpf/progs/test_sk_lookup_kern.c  | 18 +++++++++---------
 2 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/reference_tracking.c b/tools/testing/selftests/bpf/prog_tests/reference_tracking.c
index 86cee820d4d3..4493ba277bd7 100644
--- a/tools/testing/selftests/bpf/prog_tests/reference_tracking.c
+++ b/tools/testing/selftests/bpf/prog_tests/reference_tracking.c
@@ -31,7 +31,8 @@ void test_reference_tracking(void)
 		if (strstr(title, ".text") != NULL)
 			continue;
 
-		bpf_program__set_type(prog, BPF_PROG_TYPE_SCHED_CLS);
+		if (!test__start_subtest(title))
+			continue;
 
 		/* Expect verifier failure if test name has 'fail' */
 		if (strstr(title, "fail") != NULL) {
diff --git a/tools/testing/selftests/bpf/progs/test_sk_lookup_kern.c b/tools/testing/selftests/bpf/progs/test_sk_lookup_kern.c
index e21cd736c196..cb49ccb707d1 100644
--- a/tools/testing/selftests/bpf/progs/test_sk_lookup_kern.c
+++ b/tools/testing/selftests/bpf/progs/test_sk_lookup_kern.c
@@ -53,7 +53,7 @@ static struct bpf_sock_tuple *get_tuple(void *data, __u64 nh_off,
 	return result;
 }
 
-SEC("sk_lookup_success")
+SEC("classifier/sk_lookup_success")
 int bpf_sk_lookup_test0(struct __sk_buff *skb)
 {
 	void *data_end = (void *)(long)skb->data_end;
@@ -78,7 +78,7 @@ int bpf_sk_lookup_test0(struct __sk_buff *skb)
 	return sk ? TC_ACT_OK : TC_ACT_UNSPEC;
 }
 
-SEC("sk_lookup_success_simple")
+SEC("classifier/sk_lookup_success_simple")
 int bpf_sk_lookup_test1(struct __sk_buff *skb)
 {
 	struct bpf_sock_tuple tuple = {};
@@ -90,7 +90,7 @@ int bpf_sk_lookup_test1(struct __sk_buff *skb)
 	return 0;
 }
 
-SEC("fail_use_after_free")
+SEC("classifier/fail_use_after_free")
 int bpf_sk_lookup_uaf(struct __sk_buff *skb)
 {
 	struct bpf_sock_tuple tuple = {};
@@ -105,7 +105,7 @@ int bpf_sk_lookup_uaf(struct __sk_buff *skb)
 	return family;
 }
 
-SEC("fail_modify_sk_pointer")
+SEC("classifier/fail_modify_sk_pointer")
 int bpf_sk_lookup_modptr(struct __sk_buff *skb)
 {
 	struct bpf_sock_tuple tuple = {};
@@ -120,7 +120,7 @@ int bpf_sk_lookup_modptr(struct __sk_buff *skb)
 	return 0;
 }
 
-SEC("fail_modify_sk_or_null_pointer")
+SEC("classifier/fail_modify_sk_or_null_pointer")
 int bpf_sk_lookup_modptr_or_null(struct __sk_buff *skb)
 {
 	struct bpf_sock_tuple tuple = {};
@@ -134,7 +134,7 @@ int bpf_sk_lookup_modptr_or_null(struct __sk_buff *skb)
 	return 0;
 }
 
-SEC("fail_no_release")
+SEC("classifier/fail_no_release")
 int bpf_sk_lookup_test2(struct __sk_buff *skb)
 {
 	struct bpf_sock_tuple tuple = {};
@@ -143,7 +143,7 @@ int bpf_sk_lookup_test2(struct __sk_buff *skb)
 	return 0;
 }
 
-SEC("fail_release_twice")
+SEC("classifier/fail_release_twice")
 int bpf_sk_lookup_test3(struct __sk_buff *skb)
 {
 	struct bpf_sock_tuple tuple = {};
@@ -155,7 +155,7 @@ int bpf_sk_lookup_test3(struct __sk_buff *skb)
 	return 0;
 }
 
-SEC("fail_release_unchecked")
+SEC("classifier/fail_release_unchecked")
 int bpf_sk_lookup_test4(struct __sk_buff *skb)
 {
 	struct bpf_sock_tuple tuple = {};
@@ -172,7 +172,7 @@ void lookup_no_release(struct __sk_buff *skb)
 	bpf_sk_lookup_tcp(skb, &tuple, sizeof(tuple), BPF_F_CURRENT_NETNS, 0);
 }
 
-SEC("fail_no_release_subcall")
+SEC("classifier/fail_no_release_subcall")
 int bpf_sk_lookup_test5(struct __sk_buff *skb)
 {
 	lookup_no_release(skb);
-- 
2.17.1

[PATCH bpf-next 7/7] selftest/bpf: get rid of a bunch of explicit BPF program type setting

[Andrii Nakryiko]

Now that libbpf can correctly guess BPF program types from section
names, remove a bunch of explicit bpf_program__set_type() calls
throughout tests.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
---
 tools/testing/selftests/bpf/prog_tests/attach_probe.c | 5 -----
 tools/testing/selftests/bpf/prog_tests/core_reloc.c   | 1 -
 tools/testing/selftests/bpf/prog_tests/rdonly_maps.c  | 4 ----
 tools/testing/selftests/bpf/test_maps.c               | 4 ----
 4 files changed, 14 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/attach_probe.c b/tools/testing/selftests/bpf/prog_tests/attach_probe.c
index 4f50d32c4abb..0ee1ce100a4a 100644
--- a/tools/testing/selftests/bpf/prog_tests/attach_probe.c
+++ b/tools/testing/selftests/bpf/prog_tests/attach_probe.c
@@ -99,11 +99,6 @@ void test_attach_probe(void)
 		  "prog '%s' not found\n", uretprobe_name))
 		goto cleanup;
 
-	bpf_program__set_kprobe(kprobe_prog);
-	bpf_program__set_kprobe(kretprobe_prog);
-	bpf_program__set_kprobe(uprobe_prog);
-	bpf_program__set_kprobe(uretprobe_prog);
-
 	/* create maps && load programs */
 	err = bpf_object__load(obj);
 	if (CHECK(err, "obj_load", "err %d\n", err))
diff --git a/tools/testing/selftests/bpf/prog_tests/core_reloc.c b/tools/testing/selftests/bpf/prog_tests/core_reloc.c
index 2b3586dc6c86..523dca82dc82 100644
--- a/tools/testing/selftests/bpf/prog_tests/core_reloc.c
+++ b/tools/testing/selftests/bpf/prog_tests/core_reloc.c
@@ -391,7 +391,6 @@ void test_core_reloc(void)
 		if (CHECK(!prog, "find_probe",
 			  "prog '%s' not found\n", probe_name))
 			goto cleanup;
-		bpf_program__set_type(prog, BPF_PROG_TYPE_RAW_TRACEPOINT);
 
 		load_attr.obj = obj;
 		load_attr.log_level = 0;
diff --git a/tools/testing/selftests/bpf/prog_tests/rdonly_maps.c b/tools/testing/selftests/bpf/prog_tests/rdonly_maps.c
index 9bf9de0aaeea..d90acc13d1ec 100644
--- a/tools/testing/selftests/bpf/prog_tests/rdonly_maps.c
+++ b/tools/testing/selftests/bpf/prog_tests/rdonly_maps.c
@@ -36,10 +36,6 @@ void test_rdonly_maps(void)
 	if (CHECK(IS_ERR(obj), "obj_open", "err %ld\n", PTR_ERR(obj)))
 		return;
 
-	bpf_object__for_each_program(prog, obj) {
-		bpf_program__set_raw_tracepoint(prog);
-	}
-
 	err = bpf_object__load(obj);
 	if (CHECK(err, "obj_load", "err %d errno %d\n", err, errno))
 		goto cleanup;
diff --git a/tools/testing/selftests/bpf/test_maps.c b/tools/testing/selftests/bpf/test_maps.c
index 806b298397d3..02eae1e864c2 100644
--- a/tools/testing/selftests/bpf/test_maps.c
+++ b/tools/testing/selftests/bpf/test_maps.c
@@ -1142,7 +1142,6 @@ static void test_sockmap(unsigned int tasks, void *data)
 #define MAPINMAP_PROG "./test_map_in_map.o"
 static void test_map_in_map(void)
 {
-	struct bpf_program *prog;
 	struct bpf_object *obj;
 	struct bpf_map *map;
 	int mim_fd, fd, err;
@@ -1179,9 +1178,6 @@ static void test_map_in_map(void)
 		goto out_map_in_map;
 	}
 
-	bpf_object__for_each_program(prog, obj) {
-		bpf_program__set_xdp(prog);
-	}
 	bpf_object__load(obj);
 
 	map = bpf_object__find_map_by_name(obj, "mim_array");
-- 
2.17.1

Re: [PATCH bpf-next 0/7] Auto-guess program type on bpf_object__open

[Daniel Borkmann]

On Sun, Oct 20, 2019 at 08:38:55PM -0700, Andrii Nakryiko wrote:
> This patch set's main goal is to teach bpf_object__open() (and its variants)
> to automatically derive BPF program type/expected attach type from section
> names, similarly to how bpf_prog_load() was doing it. This significantly
> improves user experience by eliminating yet another
> obvious-only-in-the-hindsight surprise, when using libbpf APIs.
> 
> There are a bunch of auxiliary clean-ups and improvements. E.g.,
> bpf_program__get_type() and bpf_program__get_expected_attach_type() are added
> for completeness and symmetry with corresponding setter APIs. Some clean up
> and fixes in selftests/bpf are done as well.
> 
> Andrii Nakryiko (7):
>   tools: sync if_link.h
>   libbpf: add bpf_program__get_{type, expected_attach_type) APIs
>   libbpf: add uprobe/uretprobe and tp/raw_tp section suffixes
>   libbpf: teach bpf_object__open to guess program types
>   selftests/bpf: make a copy of subtest name
>   selftests/bpf: make reference_tracking test use subtests
>   selftest/bpf: get rid of a bunch of explicit BPF program type setting

Looks good, applied, thanks!