[PATCH bpf-next v4 0/9] bpf/selftests: page size fixes

[PATCH bpf-next v4 0/9] bpf/selftests: page size fixes

[Yauheni Kaliuta]

A set of fixes for selftests to make them working on systems with PAGE_SIZE > 4K
+ cleanup (version) and ringbuf_multi extention.

--
v3->v4:
- zero initialize BPF programs' static variables;
- add bpf_map__inner_map to libbpf.map in alphabetical order;
- add bpf_map__set_inner_map_fd test to ringbuf_multi;

v2->v3:
 - reorder: move version removing patch first to keep main patches in
   one group;
 - rename "selftests/bpf: pass page size from userspace in sockopt_sk"
   as suggested;
 - convert sockopt_sk test to use ASSERT macros;
 - set page size from userspace
 - split patches to pairs userspace/bpf. It's easier to check that
   every conversion works as expected;

v1->v2:

- add missed 'selftests/bpf: test_progs/sockopt_sk: Convert to use BPF skeleton'



Yauheni Kaliuta (9):
  selftests/bpf: test_progs/sockopt_sk: remove version
  selftests/bpf: test_progs/sockopt_sk: Convert to use BPF skeleton
  selftests/bpf: pass page size from userspace in sockopt_sk
  selftests/bpf: pass page size from userspace in map_ptr
  selftests/bpf: mmap: use runtime page size
  selftests/bpf: ringbuf: use runtime page size
  libbpf: add bpf_map__inner_map API
  selftests/bpf: ringbuf_multi: use runtime page size
  selftests/bpf: ringbuf_multi: test bpf_map__set_inner_map_fd

 tools/lib/bpf/libbpf.c                        | 10 +++
 tools/lib/bpf/libbpf.h                        |  1 +
 tools/lib/bpf/libbpf.map                      |  1 +
 .../selftests/bpf/prog_tests/map_ptr.c        | 15 ++++-
 tools/testing/selftests/bpf/prog_tests/mmap.c | 24 +++++--
 .../selftests/bpf/prog_tests/ringbuf.c        | 17 +++--
 .../selftests/bpf/prog_tests/ringbuf_multi.c  | 34 +++++++++-
 .../selftests/bpf/prog_tests/sockopt_sk.c     | 65 +++++--------------
 .../selftests/bpf/progs/map_ptr_kern.c        |  4 +-
 .../testing/selftests/bpf/progs/sockopt_sk.c  | 11 ++--
 tools/testing/selftests/bpf/progs/test_mmap.c |  2 -
 .../selftests/bpf/progs/test_ringbuf.c        |  1 -
 .../selftests/bpf/progs/test_ringbuf_multi.c  | 12 +++-
 13 files changed, 123 insertions(+), 74 deletions(-)

-- 
2.31.1

[PATCH bpf-next v4 1/9] selftests/bpf: test_progs/sockopt_sk: remove version

[Yauheni Kaliuta]

As pointed by Andrii Nakryiko, _version is useless now, remove it.

Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
---
 tools/testing/selftests/bpf/progs/sockopt_sk.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/tools/testing/selftests/bpf/progs/sockopt_sk.c b/tools/testing/selftests/bpf/progs/sockopt_sk.c
index d3597f81e6e9..978a68005966 100644
--- a/tools/testing/selftests/bpf/progs/sockopt_sk.c
+++ b/tools/testing/selftests/bpf/progs/sockopt_sk.c
@@ -6,7 +6,6 @@
 #include <bpf/bpf_helpers.h>
 
 char _license[] SEC("license") = "GPL";
-__u32 _version SEC("version") = 1;
 
 #ifndef PAGE_SIZE
 #define PAGE_SIZE 4096
-- 
2.31.1

[PATCH bpf-next v4 2/9] selftests/bpf: test_progs/sockopt_sk: Convert to use BPF skeleton

[Yauheni Kaliuta]

Switch the test to use BPF skeleton to save some boilerplate and
make it easy to access bpf program bss segment.

The latter will be used to pass PAGE_SIZE from userspace since there
is no convenient way for bpf program to get it from inside of the
kernel.

Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
---
 .../selftests/bpf/prog_tests/sockopt_sk.c     | 65 +++++--------------
 1 file changed, 17 insertions(+), 48 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c b/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c
index d5b44b135c00..7274b12abe17 100644
--- a/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c
+++ b/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c
@@ -3,6 +3,7 @@
 #include "cgroup_helpers.h"
 
 #include <linux/tcp.h>
+#include "sockopt_sk.skel.h"
 
 #ifndef SOL_TCP
 #define SOL_TCP IPPROTO_TCP
@@ -191,60 +192,28 @@ static int getsetsockopt(void)
 	return -1;
 }
 
-static int prog_attach(struct bpf_object *obj, int cgroup_fd, const char *title)
-{
-	enum bpf_attach_type attach_type;
-	enum bpf_prog_type prog_type;
-	struct bpf_program *prog;
-	int err;
-
-	err = libbpf_prog_type_by_name(title, &prog_type, &attach_type);
-	if (err) {
-		log_err("Failed to deduct types for %s BPF program", title);
-		return -1;
-	}
-
-	prog = bpf_object__find_program_by_title(obj, title);
-	if (!prog) {
-		log_err("Failed to find %s BPF program", title);
-		return -1;
-	}
-
-	err = bpf_prog_attach(bpf_program__fd(prog), cgroup_fd,
-			      attach_type, 0);
-	if (err) {
-		log_err("Failed to attach %s BPF program", title);
-		return -1;
-	}
-
-	return 0;
-}
-
 static void run_test(int cgroup_fd)
 {
-	struct bpf_prog_load_attr attr = {
-		.file = "./sockopt_sk.o",
-	};
-	struct bpf_object *obj;
-	int ignored;
-	int err;
-
-	err = bpf_prog_load_xattr(&attr, &obj, &ignored);
-	if (CHECK_FAIL(err))
-		return;
+	struct sockopt_sk *skel;
+
+	skel = sockopt_sk__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "skel_load"))
+		goto cleanup;
 
-	err = prog_attach(obj, cgroup_fd, "cgroup/getsockopt");
-	if (CHECK_FAIL(err))
-		goto close_bpf_object;
+	skel->links._setsockopt =
+		bpf_program__attach_cgroup(skel->progs._setsockopt, cgroup_fd);
+	if (!ASSERT_OK_PTR(skel->links._setsockopt, "setsockopt_link"))
+		goto cleanup;
 
-	err = prog_attach(obj, cgroup_fd, "cgroup/setsockopt");
-	if (CHECK_FAIL(err))
-		goto close_bpf_object;
+	skel->links._getsockopt =
+		bpf_program__attach_cgroup(skel->progs._getsockopt, cgroup_fd);
+	if (!ASSERT_OK_PTR(skel->links._getsockopt, "getsockopt_link"))
+		goto cleanup;
 
-	CHECK_FAIL(getsetsockopt());
+	ASSERT_OK(getsetsockopt(), "getsetsockopt");
 
-close_bpf_object:
-	bpf_object__close(obj);
+cleanup:
+	sockopt_sk__destroy(skel);
 }
 
 void test_sockopt_sk(void)
-- 
2.31.1

[PATCH bpf-next v4 3/9] selftests/bpf: pass page size from userspace in sockopt_sk

[Yauheni Kaliuta]

Since there is no convenient way for bpf program to get PAGE_SIZE
from inside of the kernel, pass the value from userspace.

Zero-initialize the variable in bpf prog, otherwise it will cause
problems on some versions of Clang.

Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
---
 tools/testing/selftests/bpf/prog_tests/sockopt_sk.c |  2 ++
 tools/testing/selftests/bpf/progs/sockopt_sk.c      | 10 ++++------
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c b/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c
index 7274b12abe17..4b937e5dbaca 100644
--- a/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c
+++ b/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c
@@ -200,6 +200,8 @@ static void run_test(int cgroup_fd)
 	if (!ASSERT_OK_PTR(skel, "skel_load"))
 		goto cleanup;
 
+	skel->bss->page_size = getpagesize();
+
 	skel->links._setsockopt =
 		bpf_program__attach_cgroup(skel->progs._setsockopt, cgroup_fd);
 	if (!ASSERT_OK_PTR(skel->links._setsockopt, "setsockopt_link"))
diff --git a/tools/testing/selftests/bpf/progs/sockopt_sk.c b/tools/testing/selftests/bpf/progs/sockopt_sk.c
index 978a68005966..8acdb99b5959 100644
--- a/tools/testing/selftests/bpf/progs/sockopt_sk.c
+++ b/tools/testing/selftests/bpf/progs/sockopt_sk.c
@@ -7,9 +7,7 @@
 
 char _license[] SEC("license") = "GPL";
 
-#ifndef PAGE_SIZE
-#define PAGE_SIZE 4096
-#endif
+int page_size = 0; /* userspace should set it */
 
 #ifndef SOL_TCP
 #define SOL_TCP IPPROTO_TCP
@@ -89,7 +87,7 @@ int _getsockopt(struct bpf_sockopt *ctx)
 		 * program can only see the first PAGE_SIZE
 		 * bytes of data.
 		 */
-		if (optval_end - optval != PAGE_SIZE)
+		if (optval_end - optval != page_size)
 			return 0; /* EPERM, unexpected data size */
 
 		return 1;
@@ -160,7 +158,7 @@ int _setsockopt(struct bpf_sockopt *ctx)
 
 	if (ctx->level == SOL_IP && ctx->optname == IP_FREEBIND) {
 		/* Original optlen is larger than PAGE_SIZE. */
-		if (ctx->optlen != PAGE_SIZE * 2)
+		if (ctx->optlen != page_size * 2)
 			return 0; /* EPERM, unexpected data size */
 
 		if (optval + 1 > optval_end)
@@ -174,7 +172,7 @@ int _setsockopt(struct bpf_sockopt *ctx)
 		 * program can only see the first PAGE_SIZE
 		 * bytes of data.
 		 */
-		if (optval_end - optval != PAGE_SIZE)
+		if (optval_end - optval != page_size)
 			return 0; /* EPERM, unexpected data size */
 
 		return 1;
-- 
2.31.1

[PATCH bpf-next v4 4/9] selftests/bpf: pass page size from userspace in map_ptr

[Yauheni Kaliuta]

Use ASSERT to check result but keep CHECK where format was used to
report error.

Use bpf_map__set_max_entries() to set map size dynamically from
userspace according to page size.

Zero-initialize the variable in bpf prog, otherwise it will cause
problems on some versions of Clang.

Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
---
 tools/testing/selftests/bpf/prog_tests/map_ptr.c | 15 +++++++++++++--
 tools/testing/selftests/bpf/progs/map_ptr_kern.c |  4 ++--
 2 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/map_ptr.c b/tools/testing/selftests/bpf/prog_tests/map_ptr.c
index c230a573c373..4972f92205c7 100644
--- a/tools/testing/selftests/bpf/prog_tests/map_ptr.c
+++ b/tools/testing/selftests/bpf/prog_tests/map_ptr.c
@@ -12,11 +12,22 @@ void test_map_ptr(void)
 	__u32 duration = 0, retval;
 	char buf[128];
 	int err;
+	int page_size = getpagesize();
 
-	skel = map_ptr_kern__open_and_load();
-	if (CHECK(!skel, "skel_open_load", "open_load failed\n"))
+	skel = map_ptr_kern__open();
+	if (!ASSERT_OK_PTR(skel, "skel_open"))
 		return;
 
+	err = bpf_map__set_max_entries(skel->maps.m_ringbuf, page_size);
+	if (!ASSERT_OK(err, "bpf_map__set_max_entries"))
+		goto cleanup;
+
+	err = map_ptr_kern__load(skel);
+	if (!ASSERT_OK(err, "skel_load"))
+		goto cleanup;
+
+	skel->bss->page_size = page_size;
+
 	err = bpf_prog_test_run(bpf_program__fd(skel->progs.cg_skb), 1, &pkt_v4,
 				sizeof(pkt_v4), buf, NULL, &retval, NULL);
 
diff --git a/tools/testing/selftests/bpf/progs/map_ptr_kern.c b/tools/testing/selftests/bpf/progs/map_ptr_kern.c
index d8850bc6a9f1..d1d304c980f0 100644
--- a/tools/testing/selftests/bpf/progs/map_ptr_kern.c
+++ b/tools/testing/selftests/bpf/progs/map_ptr_kern.c
@@ -12,6 +12,7 @@ _Static_assert(MAX_ENTRIES < LOOP_BOUND, "MAX_ENTRIES must be < LOOP_BOUND");
 
 enum bpf_map_type g_map_type = BPF_MAP_TYPE_UNSPEC;
 __u32 g_line = 0;
+int page_size = 0; /* userspace should set it */
 
 #define VERIFY_TYPE(type, func) ({	\
 	g_map_type = type;		\
@@ -635,7 +636,6 @@ struct bpf_ringbuf_map {
 
 struct {
 	__uint(type, BPF_MAP_TYPE_RINGBUF);
-	__uint(max_entries, 1 << 12);
 } m_ringbuf SEC(".maps");
 
 static inline int check_ringbuf(void)
@@ -643,7 +643,7 @@ static inline int check_ringbuf(void)
 	struct bpf_ringbuf_map *ringbuf = (struct bpf_ringbuf_map *)&m_ringbuf;
 	struct bpf_map *map = (struct bpf_map *)&m_ringbuf;
 
-	VERIFY(check(&ringbuf->map, map, 0, 0, 1 << 12));
+	VERIFY(check(&ringbuf->map, map, 0, 0, page_size));
 
 	return 1;
 }
-- 
2.31.1

[PATCH bpf-next v4 5/9] selftests/bpf: mmap: use runtime page size

[Yauheni Kaliuta]

Replace hardcoded 4096 with runtime value in the userspace part of
the test and set bpf table sizes dynamically according to the value.

Do not switch to ASSERT macros, keep CHECK, for consistency with the
rest of the test. Can be a separate cleanup patch.

Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
---
 tools/testing/selftests/bpf/prog_tests/mmap.c | 24 +++++++++++++++----
 tools/testing/selftests/bpf/progs/test_mmap.c |  2 --
 2 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/mmap.c b/tools/testing/selftests/bpf/prog_tests/mmap.c
index 9c3c5c0f068f..37b002ca1167 100644
--- a/tools/testing/selftests/bpf/prog_tests/mmap.c
+++ b/tools/testing/selftests/bpf/prog_tests/mmap.c
@@ -29,22 +29,36 @@ void test_mmap(void)
 	struct test_mmap *skel;
 	__u64 val = 0;
 
-	skel = test_mmap__open_and_load();
-	if (CHECK(!skel, "skel_open_and_load", "skeleton open/load failed\n"))
+	skel = test_mmap__open();
+	if (CHECK(!skel, "skel_open", "skeleton open failed\n"))
 		return;
 
+	err = bpf_map__set_max_entries(skel->maps.rdonly_map, page_size);
+	if (CHECK(err != 0, "bpf_map__set_max_entries", "bpf_map__set_max_entries failed\n"))
+		goto cleanup;
+
+	/* at least 4 pages of data */
+	err = bpf_map__set_max_entries(skel->maps.data_map,
+				       4 * (page_size / sizeof(u64)));
+	if (CHECK(err != 0, "bpf_map__set_max_entries", "bpf_map__set_max_entries failed\n"))
+		goto cleanup;
+
+	err = test_mmap__load(skel);
+	if (CHECK(err != 0, "skel_load", "skeleton load failed\n"))
+		goto cleanup;
+
 	bss_map = skel->maps.bss;
 	data_map = skel->maps.data_map;
 	data_map_fd = bpf_map__fd(data_map);
 
 	rdmap_fd = bpf_map__fd(skel->maps.rdonly_map);
-	tmp1 = mmap(NULL, 4096, PROT_READ | PROT_WRITE, MAP_SHARED, rdmap_fd, 0);
+	tmp1 = mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_SHARED, rdmap_fd, 0);
 	if (CHECK(tmp1 != MAP_FAILED, "rdonly_write_mmap", "unexpected success\n")) {
-		munmap(tmp1, 4096);
+		munmap(tmp1, page_size);
 		goto cleanup;
 	}
 	/* now double-check if it's mmap()'able at all */
-	tmp1 = mmap(NULL, 4096, PROT_READ, MAP_SHARED, rdmap_fd, 0);
+	tmp1 = mmap(NULL, page_size, PROT_READ, MAP_SHARED, rdmap_fd, 0);
 	if (CHECK(tmp1 == MAP_FAILED, "rdonly_read_mmap", "failed: %d\n", errno))
 		goto cleanup;
 
diff --git a/tools/testing/selftests/bpf/progs/test_mmap.c b/tools/testing/selftests/bpf/progs/test_mmap.c
index 4eb42cff5fe9..5a5cc19a15bf 100644
--- a/tools/testing/selftests/bpf/progs/test_mmap.c
+++ b/tools/testing/selftests/bpf/progs/test_mmap.c
@@ -9,7 +9,6 @@ char _license[] SEC("license") = "GPL";
 
 struct {
 	__uint(type, BPF_MAP_TYPE_ARRAY);
-	__uint(max_entries, 4096);
 	__uint(map_flags, BPF_F_MMAPABLE | BPF_F_RDONLY_PROG);
 	__type(key, __u32);
 	__type(value, char);
@@ -17,7 +16,6 @@ struct {
 
 struct {
 	__uint(type, BPF_MAP_TYPE_ARRAY);
-	__uint(max_entries, 512 * 4); /* at least 4 pages of data */
 	__uint(map_flags, BPF_F_MMAPABLE);
 	__type(key, __u32);
 	__type(value, __u64);
-- 
2.31.1

[PATCH bpf-next v4 6/9] selftests/bpf: ringbuf: use runtime page size

[Yauheni Kaliuta]

Replace hardcoded 4096 with runtime value in the userspace part of
the test and set bpf table sizes dynamically according to the value.

Do not switch to ASSERT macros, keep CHECK, for consistency with the
rest of the test. Can be a separate cleanup patch.

Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
---
 .../testing/selftests/bpf/prog_tests/ringbuf.c  | 17 +++++++++++++----
 .../testing/selftests/bpf/progs/test_ringbuf.c  |  1 -
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/ringbuf.c b/tools/testing/selftests/bpf/prog_tests/ringbuf.c
index fddbc5db5d6a..de78617f6550 100644
--- a/tools/testing/selftests/bpf/prog_tests/ringbuf.c
+++ b/tools/testing/selftests/bpf/prog_tests/ringbuf.c
@@ -87,11 +87,20 @@ void test_ringbuf(void)
 	pthread_t thread;
 	long bg_ret = -1;
 	int err, cnt;
+	int page_size = getpagesize();
 
-	skel = test_ringbuf__open_and_load();
-	if (CHECK(!skel, "skel_open_load", "skeleton open&load failed\n"))
+	skel = test_ringbuf__open();
+	if (CHECK(!skel, "skel_open", "skeleton open failed\n"))
 		return;
 
+	err = bpf_map__set_max_entries(skel->maps.ringbuf, page_size);
+	if (CHECK(err != 0, "bpf_map__set_max_entries", "bpf_map__set_max_entries failed\n"))
+		goto cleanup;
+
+	err = test_ringbuf__load(skel);
+	if (CHECK(err != 0, "skel_load", "skeleton load failed\n"))
+		goto cleanup;
+
 	/* only trigger BPF program for current process */
 	skel->bss->pid = getpid();
 
@@ -110,9 +119,9 @@ void test_ringbuf(void)
 	CHECK(skel->bss->avail_data != 3 * rec_sz,
 	      "err_avail_size", "exp %ld, got %ld\n",
 	      3L * rec_sz, skel->bss->avail_data);
-	CHECK(skel->bss->ring_size != 4096,
+	CHECK(skel->bss->ring_size != page_size,
 	      "err_ring_size", "exp %ld, got %ld\n",
-	      4096L, skel->bss->ring_size);
+	      (long)page_size, skel->bss->ring_size);
 	CHECK(skel->bss->cons_pos != 0,
 	      "err_cons_pos", "exp %ld, got %ld\n",
 	      0L, skel->bss->cons_pos);
diff --git a/tools/testing/selftests/bpf/progs/test_ringbuf.c b/tools/testing/selftests/bpf/progs/test_ringbuf.c
index 8ba9959b036b..6b3f288b7c63 100644
--- a/tools/testing/selftests/bpf/progs/test_ringbuf.c
+++ b/tools/testing/selftests/bpf/progs/test_ringbuf.c
@@ -15,7 +15,6 @@ struct sample {
 
 struct {
 	__uint(type, BPF_MAP_TYPE_RINGBUF);
-	__uint(max_entries, 1 << 12);
 } ringbuf SEC(".maps");
 
 /* inputs */
-- 
2.31.1

[PATCH bpf-next v4 7/9] libbpf: add bpf_map__inner_map API

[Yauheni Kaliuta]

From: Andrii Nakryiko <andrii.nakryiko@gmail.com>

The API gives access to inner map for map in map types (array or
hash of map). It will be used to dynamically set max_entries in it.

Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
---
 tools/lib/bpf/libbpf.c   | 10 ++++++++++
 tools/lib/bpf/libbpf.h   |  1 +
 tools/lib/bpf/libbpf.map |  1 +
 3 files changed, 12 insertions(+)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 7aad78dbb4b4..ed5586cce227 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -2194,6 +2194,7 @@ static int parse_btf_map_def(struct bpf_object *obj,
 			map->inner_map = calloc(1, sizeof(*map->inner_map));
 			if (!map->inner_map)
 				return -ENOMEM;
+			map->inner_map->fd = -1;
 			map->inner_map->sec_idx = obj->efile.btf_maps_shndx;
 			map->inner_map->name = malloc(strlen(map->name) +
 						      sizeof(".inner") + 1);
@@ -3845,6 +3846,14 @@ __u32 bpf_map__max_entries(const struct bpf_map *map)
 	return map->def.max_entries;
 }
 
+struct bpf_map *bpf_map__inner_map(struct bpf_map *map)
+{
+	if (!bpf_map_type__is_map_in_map(map->def.type))
+		return NULL;
+
+	return map->inner_map;
+}
+
 int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries)
 {
 	if (map->fd >= 0)
@@ -9476,6 +9485,7 @@ int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd)
 		pr_warn("error: inner_map_fd already specified\n");
 		return -EINVAL;
 	}
+	zfree(&map->inner_map);
 	map->inner_map_fd = fd;
 	return 0;
 }
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index f500621d28e5..bec4e6a6e31d 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -480,6 +480,7 @@ LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path);
 LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path);
 
 LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd);
+LIBBPF_API struct bpf_map *bpf_map__inner_map(struct bpf_map *map);
 
 LIBBPF_API long libbpf_get_error(const void *ptr);
 
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index f5990f7208ce..9768daa75415 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -349,6 +349,7 @@ LIBBPF_0.3.0 {
 		ring_buffer__epoll_fd;
 		xsk_setup_xdp_prog;
 		xsk_socket__update_xskmap;
+		bpf_map__inner_map;
 } LIBBPF_0.2.0;
 
 LIBBPF_0.4.0 {
-- 
2.31.1

Re: [PATCH bpf-next v4 7/9] libbpf: add bpf_map__inner_map API

[Andrii Nakryiko]

On Wed, Apr 7, 2021 at 11:14 PM Yauheni Kaliuta
<yauheni.kaliuta@redhat.com> wrote:
>
> From: Andrii Nakryiko <andrii.nakryiko@gmail.com>
>
> The API gives access to inner map for map in map types (array or
> hash of map). It will be used to dynamically set max_entries in it.
>
> Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
> ---
>  tools/lib/bpf/libbpf.c   | 10 ++++++++++
>  tools/lib/bpf/libbpf.h   |  1 +
>  tools/lib/bpf/libbpf.map |  1 +
>  3 files changed, 12 insertions(+)
>
> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
> index 7aad78dbb4b4..ed5586cce227 100644
> --- a/tools/lib/bpf/libbpf.c
> +++ b/tools/lib/bpf/libbpf.c
> @@ -2194,6 +2194,7 @@ static int parse_btf_map_def(struct bpf_object *obj,
>                         map->inner_map = calloc(1, sizeof(*map->inner_map));
>                         if (!map->inner_map)
>                                 return -ENOMEM;
> +                       map->inner_map->fd = -1;
>                         map->inner_map->sec_idx = obj->efile.btf_maps_shndx;
>                         map->inner_map->name = malloc(strlen(map->name) +
>                                                       sizeof(".inner") + 1);
> @@ -3845,6 +3846,14 @@ __u32 bpf_map__max_entries(const struct bpf_map *map)
>         return map->def.max_entries;
>  }
>
> +struct bpf_map *bpf_map__inner_map(struct bpf_map *map)
> +{
> +       if (!bpf_map_type__is_map_in_map(map->def.type))
> +               return NULL;
> +
> +       return map->inner_map;
> +}
> +
>  int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries)
>  {
>         if (map->fd >= 0)
> @@ -9476,6 +9485,7 @@ int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd)
>                 pr_warn("error: inner_map_fd already specified\n");
>                 return -EINVAL;
>         }
> +       zfree(&map->inner_map);
>         map->inner_map_fd = fd;
>         return 0;
>  }
> diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
> index f500621d28e5..bec4e6a6e31d 100644
> --- a/tools/lib/bpf/libbpf.h
> +++ b/tools/lib/bpf/libbpf.h
> @@ -480,6 +480,7 @@ LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path);
>  LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path);
>
>  LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd);
> +LIBBPF_API struct bpf_map *bpf_map__inner_map(struct bpf_map *map);
>
>  LIBBPF_API long libbpf_get_error(const void *ptr);
>
> diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
> index f5990f7208ce..9768daa75415 100644
> --- a/tools/lib/bpf/libbpf.map
> +++ b/tools/lib/bpf/libbpf.map
> @@ -349,6 +349,7 @@ LIBBPF_0.3.0 {
>                 ring_buffer__epoll_fd;
>                 xsk_setup_xdp_prog;
>                 xsk_socket__update_xskmap;
> +               bpf_map__inner_map;

This is neither in the right version (should be in 0.4.0) nor is in
alphabetical order (despite cover letter saying otherwise).
But I've fixed it up while applying. Please be more careful next time.

>  } LIBBPF_0.2.0;
>
>  LIBBPF_0.4.0 {

> --
> 2.31.1
>

[PATCH bpf-next v4 8/9] selftests/bpf: ringbuf_multi: use runtime page size

[Yauheni Kaliuta]

Set bpf table sizes dynamically according to the runtime page size
value.

Do not switch to ASSERT macros, keep CHECK, for consistency with the
rest of the test. Can be a separate cleanup patch.

Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
---
 .../selftests/bpf/prog_tests/ringbuf_multi.c  | 23 ++++++++++++++++---
 .../selftests/bpf/progs/test_ringbuf_multi.c  |  1 -
 2 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c b/tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c
index d37161e59bb2..159de99621c7 100644
--- a/tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c
+++ b/tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c
@@ -41,13 +41,30 @@ static int process_sample(void *ctx, void *data, size_t len)
 void test_ringbuf_multi(void)
 {
 	struct test_ringbuf_multi *skel;
-	struct ring_buffer *ringbuf;
+	struct ring_buffer *ringbuf = NULL;
 	int err;
+	int page_size = getpagesize();
 
-	skel = test_ringbuf_multi__open_and_load();
-	if (CHECK(!skel, "skel_open_load", "skeleton open&load failed\n"))
+	skel = test_ringbuf_multi__open();
+	if (CHECK(!skel, "skel_open", "skeleton open failed\n"))
 		return;
 
+	err = bpf_map__set_max_entries(skel->maps.ringbuf1, page_size);
+	if (CHECK(err != 0, "bpf_map__set_max_entries", "bpf_map__set_max_entries failed\n"))
+		goto cleanup;
+
+	err = bpf_map__set_max_entries(skel->maps.ringbuf2, page_size);
+	if (CHECK(err != 0, "bpf_map__set_max_entries", "bpf_map__set_max_entries failed\n"))
+		goto cleanup;
+
+	err = bpf_map__set_max_entries(bpf_map__inner_map(skel->maps.ringbuf_arr), page_size);
+	if (CHECK(err != 0, "bpf_map__set_max_entries", "bpf_map__set_max_entries failed\n"))
+		goto cleanup;
+
+	err = test_ringbuf_multi__load(skel);
+	if (CHECK(err != 0, "skel_load", "skeleton load failed\n"))
+		goto cleanup;
+
 	/* only trigger BPF program for current process */
 	skel->bss->pid = getpid();
 
diff --git a/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c b/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c
index edf3b6953533..055c10b2ff80 100644
--- a/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c
+++ b/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c
@@ -15,7 +15,6 @@ struct sample {
 
 struct ringbuf_map {
 	__uint(type, BPF_MAP_TYPE_RINGBUF);
-	__uint(max_entries, 1 << 12);
 } ringbuf1 SEC(".maps"),
   ringbuf2 SEC(".maps");
 
-- 
2.31.1

[PATCH bpf-next v4 9/9] selftests/bpf: ringbuf_multi: test bpf_map__set_inner_map_fd

[Yauheni Kaliuta]

Test map__set_inner_map_fd() interaction with map-in-map
initialization. Use hashmap of maps just to make it different to
existing array of maps.

Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
---
 .../testing/selftests/bpf/prog_tests/ringbuf_multi.c  | 11 +++++++++++
 .../testing/selftests/bpf/progs/test_ringbuf_multi.c  | 11 +++++++++++
 2 files changed, 22 insertions(+)

diff --git a/tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c b/tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c
index 159de99621c7..0e79a7d28361 100644
--- a/tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c
+++ b/tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c
@@ -44,6 +44,7 @@ void test_ringbuf_multi(void)
 	struct ring_buffer *ringbuf = NULL;
 	int err;
 	int page_size = getpagesize();
+	int proto_fd;
 
 	skel = test_ringbuf_multi__open();
 	if (CHECK(!skel, "skel_open", "skeleton open failed\n"))
@@ -61,10 +62,20 @@ void test_ringbuf_multi(void)
 	if (CHECK(err != 0, "bpf_map__set_max_entries", "bpf_map__set_max_entries failed\n"))
 		goto cleanup;
 
+	proto_fd = bpf_create_map(BPF_MAP_TYPE_RINGBUF, 0, 0, page_size, 0);
+	if (CHECK(proto_fd == -1, "bpf_create_map", "bpf_create_map failed\n"))
+		goto cleanup;
+
+	err = bpf_map__set_inner_map_fd(skel->maps.ringbuf_hash, proto_fd);
+	if (CHECK(err != 0, "bpf_map__set_inner_map_fd", "bpf_map__set_inner_map_fd failed\n"))
+		goto cleanup;
+
 	err = test_ringbuf_multi__load(skel);
 	if (CHECK(err != 0, "skel_load", "skeleton load failed\n"))
 		goto cleanup;
 
+	close(proto_fd);
+
 	/* only trigger BPF program for current process */
 	skel->bss->pid = getpid();
 
diff --git a/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c b/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c
index 055c10b2ff80..197b86546dca 100644
--- a/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c
+++ b/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c
@@ -30,6 +30,17 @@ struct {
 	},
 };
 
+struct {
+	__uint(type, BPF_MAP_TYPE_HASH_OF_MAPS);
+	__uint(max_entries, 1);
+	__type(key, int);
+	__array(values, struct ringbuf_map);
+} ringbuf_hash SEC(".maps") = {
+	.values = {
+		[0] = &ringbuf1,
+	},
+};
+
 /* inputs */
 int pid = 0;
 int target_ring = 0;
-- 
2.31.1

Re: [PATCH bpf-next v4 9/9] selftests/bpf: ringbuf_multi: test bpf_map__set_inner_map_fd

[Andrii Nakryiko]

On Wed, Apr 7, 2021 at 11:14 PM Yauheni Kaliuta
<yauheni.kaliuta@redhat.com> wrote:
>
> Test map__set_inner_map_fd() interaction with map-in-map
> initialization. Use hashmap of maps just to make it different to
> existing array of maps.
>
> Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
> ---
>  .../testing/selftests/bpf/prog_tests/ringbuf_multi.c  | 11 +++++++++++
>  .../testing/selftests/bpf/progs/test_ringbuf_multi.c  | 11 +++++++++++
>  2 files changed, 22 insertions(+)
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c b/tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c
> index 159de99621c7..0e79a7d28361 100644
> --- a/tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c
> +++ b/tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c
> @@ -44,6 +44,7 @@ void test_ringbuf_multi(void)
>         struct ring_buffer *ringbuf = NULL;
>         int err;
>         int page_size = getpagesize();
> +       int proto_fd;
>
>         skel = test_ringbuf_multi__open();
>         if (CHECK(!skel, "skel_open", "skeleton open failed\n"))
> @@ -61,10 +62,20 @@ void test_ringbuf_multi(void)
>         if (CHECK(err != 0, "bpf_map__set_max_entries", "bpf_map__set_max_entries failed\n"))
>                 goto cleanup;
>
> +       proto_fd = bpf_create_map(BPF_MAP_TYPE_RINGBUF, 0, 0, page_size, 0);
> +       if (CHECK(proto_fd == -1, "bpf_create_map", "bpf_create_map failed\n"))
> +               goto cleanup;
> +
> +       err = bpf_map__set_inner_map_fd(skel->maps.ringbuf_hash, proto_fd);
> +       if (CHECK(err != 0, "bpf_map__set_inner_map_fd", "bpf_map__set_inner_map_fd failed\n"))
> +               goto cleanup;
> +
>         err = test_ringbuf_multi__load(skel);
>         if (CHECK(err != 0, "skel_load", "skeleton load failed\n"))
>                 goto cleanup;
>
> +       close(proto_fd);
> +

This will leak FD if any of two previous CHECK()s fail. Fixed it up
while applying.

>         /* only trigger BPF program for current process */
>         skel->bss->pid = getpid();
>
> diff --git a/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c b/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c
> index 055c10b2ff80..197b86546dca 100644
> --- a/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c
> +++ b/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c
> @@ -30,6 +30,17 @@ struct {
>         },
>  };
>
> +struct {
> +       __uint(type, BPF_MAP_TYPE_HASH_OF_MAPS);
> +       __uint(max_entries, 1);
> +       __type(key, int);
> +       __array(values, struct ringbuf_map);
> +} ringbuf_hash SEC(".maps") = {
> +       .values = {
> +               [0] = &ringbuf1,
> +       },
> +};
> +
>  /* inputs */
>  int pid = 0;
>  int target_ring = 0;
> --
> 2.31.1
>