diff mbox series

[v3,bpf-next,17/18] selftests/bpf: add map linking selftest

Message ID 20210423181348.1801389-18-andrii@kernel.org (mailing list archive)
State Accepted
Delegated to: BPF
Headers show
Series BPF static linker: support externs | expand

Checks

Context Check Description
netdev/cover_letter success Link
netdev/fixes_present success Link
netdev/patch_count fail Series longer than 15 patches
netdev/tree_selection success Clearly marked for bpf-next
netdev/subject_prefix success Link
netdev/cc_maintainers warning 7 maintainers not CCed: linux-kselftest@vger.kernel.org kpsingh@kernel.org kafai@fb.com ast@kernel.org john.fastabend@gmail.com songliubraving@fb.com shuah@kernel.org
netdev/source_inline success Was 0 now: 0
netdev/verify_signedoff success Link
netdev/module_param success Was 0 now: 0
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/verify_fixes success Link
netdev/checkpatch fail ERROR: trailing whitespace WARNING: added, moved or deleted file(s), does MAINTAINERS need updating? WARNING: do not add new typedefs WARNING: externs should be avoided in .c files
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/header_inline success Link

Commit Message

Andrii Nakryiko April 23, 2021, 6:13 p.m. UTC
Add selftest validating various aspects of statically linking BTF-defined map
definitions. Legacy map definitions do not support extern resolution between
object files. Some of the aspects validated:
  - correct resolution of extern maps against concrete map definitions;
  - extern maps can currently only specify map type and key/value size and/or
    type information;
  - weak concrete map definitions are resolved properly.

Static map definitions are not yet supported by libbpf, so they are not
explicitly tested, though manual testing showes that BPF linker handles them
properly.

Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
---
 tools/testing/selftests/bpf/Makefile          |  4 +-
 .../selftests/bpf/prog_tests/linked_maps.c    | 30 +++++++
 .../selftests/bpf/progs/linked_maps1.c        | 82 +++++++++++++++++++
 .../selftests/bpf/progs/linked_maps2.c        | 76 +++++++++++++++++
 4 files changed, 191 insertions(+), 1 deletion(-)
 create mode 100644 tools/testing/selftests/bpf/prog_tests/linked_maps.c
 create mode 100644 tools/testing/selftests/bpf/progs/linked_maps1.c
 create mode 100644 tools/testing/selftests/bpf/progs/linked_maps2.c

Comments

Yonghong Song April 23, 2021, 6:53 p.m. UTC | #1
On 4/23/21 11:13 AM, Andrii Nakryiko wrote:
> Add selftest validating various aspects of statically linking BTF-defined map
> definitions. Legacy map definitions do not support extern resolution between
> object files. Some of the aspects validated:
>    - correct resolution of extern maps against concrete map definitions;
>    - extern maps can currently only specify map type and key/value size and/or
>      type information;
>    - weak concrete map definitions are resolved properly.
> 
> Static map definitions are not yet supported by libbpf, so they are not
> explicitly tested, though manual testing showes that BPF linker handles them
> properly.
> 
> Acked-by: Yonghong Song <yhs@fb.com>
> Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
[...]
> +
> +SEC("raw_tp/sys_exit")
> +int BPF_PROG(handler_exit1)
> +{
> +	/* lookup values with key = 2, set in another file */
> +	int key = 2, *val;
> +	struct my_key key_struct = { .x = 2 };
> +	struct my_value *value_struct;
> +
> +	value_struct = bpf_map_lookup_elem(&map1, &key_struct);
> +	if (value_struct)
> +		output_first1 = value_struct->x;
> +
> +	val = bpf_map_lookup_elem(&map2, &key);
> +	if (val)
> +		output_second1 = *val;
> +
> +	val = bpf_map_lookup_elem(&map_weak, &key);
> +	if (val)
> +		output_weak1 = *val;
> +	

There is an extra tab in the above line. There is no need for new 
revision just for this. If no new revision is needed, maybe
the maintainer can help fix it.

> +	return 0;
> +}
Alexei Starovoitov April 23, 2021, 9:23 p.m. UTC | #2
On Fri, Apr 23, 2021 at 11:54 AM Yonghong Song <yhs@fb.com> wrote:
>
>
>
> On 4/23/21 11:13 AM, Andrii Nakryiko wrote:
> > Add selftest validating various aspects of statically linking BTF-defined map
> > definitions. Legacy map definitions do not support extern resolution between
> > object files. Some of the aspects validated:
> >    - correct resolution of extern maps against concrete map definitions;
> >    - extern maps can currently only specify map type and key/value size and/or
> >      type information;
> >    - weak concrete map definitions are resolved properly.
> >
> > Static map definitions are not yet supported by libbpf, so they are not
> > explicitly tested, though manual testing showes that BPF linker handles them
> > properly.
> >
> > Acked-by: Yonghong Song <yhs@fb.com>
> > Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
> [...]
> > +
> > +SEC("raw_tp/sys_exit")
> > +int BPF_PROG(handler_exit1)
> > +{
> > +     /* lookup values with key = 2, set in another file */
> > +     int key = 2, *val;
> > +     struct my_key key_struct = { .x = 2 };
> > +     struct my_value *value_struct;
> > +
> > +     value_struct = bpf_map_lookup_elem(&map1, &key_struct);
> > +     if (value_struct)
> > +             output_first1 = value_struct->x;
> > +
> > +     val = bpf_map_lookup_elem(&map2, &key);
> > +     if (val)
> > +             output_second1 = *val;
> > +
> > +     val = bpf_map_lookup_elem(&map_weak, &key);
> > +     if (val)
> > +             output_weak1 = *val;
> > +
>
> There is an extra tab in the above line. There is no need for new
> revision just for this. If no new revision is needed, maybe
> the maintainer can help fix it.

Sorry. I applied without it. Pls fold the fix in some of the future patches.
Andrii Nakryiko April 23, 2021, 9:39 p.m. UTC | #3
On Fri, Apr 23, 2021 at 2:23 PM Alexei Starovoitov
<alexei.starovoitov@gmail.com> wrote:
>
> On Fri, Apr 23, 2021 at 11:54 AM Yonghong Song <yhs@fb.com> wrote:
> >
> >
> >
> > On 4/23/21 11:13 AM, Andrii Nakryiko wrote:
> > > Add selftest validating various aspects of statically linking BTF-defined map
> > > definitions. Legacy map definitions do not support extern resolution between
> > > object files. Some of the aspects validated:
> > >    - correct resolution of extern maps against concrete map definitions;
> > >    - extern maps can currently only specify map type and key/value size and/or
> > >      type information;
> > >    - weak concrete map definitions are resolved properly.
> > >
> > > Static map definitions are not yet supported by libbpf, so they are not
> > > explicitly tested, though manual testing showes that BPF linker handles them
> > > properly.
> > >
> > > Acked-by: Yonghong Song <yhs@fb.com>
> > > Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
> > [...]
> > > +
> > > +SEC("raw_tp/sys_exit")
> > > +int BPF_PROG(handler_exit1)
> > > +{
> > > +     /* lookup values with key = 2, set in another file */
> > > +     int key = 2, *val;
> > > +     struct my_key key_struct = { .x = 2 };
> > > +     struct my_value *value_struct;
> > > +
> > > +     value_struct = bpf_map_lookup_elem(&map1, &key_struct);
> > > +     if (value_struct)
> > > +             output_first1 = value_struct->x;
> > > +
> > > +     val = bpf_map_lookup_elem(&map2, &key);
> > > +     if (val)
> > > +             output_second1 = *val;
> > > +
> > > +     val = bpf_map_lookup_elem(&map_weak, &key);
> > > +     if (val)
> > > +             output_weak1 = *val;
> > > +
> >
> > There is an extra tab in the above line. There is no need for new
> > revision just for this. If no new revision is needed, maybe
> > the maintainer can help fix it.
>
> Sorry. I applied without it. Pls fold the fix in some of the future patches.

Ok, no problem, I'll do it in v3 of statics support patch set.
diff mbox series

Patch

diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 411e2cf07ba5..283e5ad8385e 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -309,11 +309,13 @@  endef
 
 SKEL_BLACKLIST := btf__% test_pinning_invalid.c test_sk_assign.c
 
-LINKED_SKELS := test_static_linked.skel.h linked_funcs.skel.h linked_vars.skel.h
+LINKED_SKELS := test_static_linked.skel.h linked_funcs.skel.h		\
+		linked_vars.skel.h linked_maps.skel.h
 
 test_static_linked.skel.h-deps := test_static_linked1.o test_static_linked2.o
 linked_funcs.skel.h-deps := linked_funcs1.o linked_funcs2.o
 linked_vars.skel.h-deps := linked_vars1.o linked_vars2.o
+linked_maps.skel.h-deps := linked_maps1.o linked_maps2.o
 
 LINKED_BPF_SRCS := $(patsubst %.o,%.c,$(foreach skel,$(LINKED_SKELS),$($(skel)-deps)))
 
diff --git a/tools/testing/selftests/bpf/prog_tests/linked_maps.c b/tools/testing/selftests/bpf/prog_tests/linked_maps.c
new file mode 100644
index 000000000000..85dcaaaf2775
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/linked_maps.c
@@ -0,0 +1,30 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021 Facebook */
+
+#include <test_progs.h>
+#include <sys/syscall.h>
+#include "linked_maps.skel.h"
+
+void test_linked_maps(void)
+{
+	int err;
+	struct linked_maps *skel;
+
+	skel = linked_maps__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "skel_open"))
+		return;
+
+	err = linked_maps__attach(skel);
+	if (!ASSERT_OK(err, "skel_attach"))
+		goto cleanup;
+
+	/* trigger */
+	syscall(SYS_getpgid);
+
+	ASSERT_EQ(skel->bss->output_first1, 2000, "output_first1");
+	ASSERT_EQ(skel->bss->output_second1, 2, "output_second1");
+	ASSERT_EQ(skel->bss->output_weak1, 2, "output_weak1");
+
+cleanup:
+	linked_maps__destroy(skel);
+}
diff --git a/tools/testing/selftests/bpf/progs/linked_maps1.c b/tools/testing/selftests/bpf/progs/linked_maps1.c
new file mode 100644
index 000000000000..52291515cc72
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/linked_maps1.c
@@ -0,0 +1,82 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021 Facebook */
+
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+struct my_key { long x; };
+struct my_value { long x; };
+
+struct {
+	__uint(type, BPF_MAP_TYPE_HASH);
+	__type(key, struct my_key);
+	__type(value, struct my_value);
+	__uint(max_entries, 16);
+} map1 SEC(".maps");
+
+ /* Matches map2 definition in linked_maps2.c. Order of the attributes doesn't
+  * matter.
+  */
+typedef struct {
+	__uint(max_entries, 8);
+	__type(key, int);
+	__type(value, int);
+	__uint(type, BPF_MAP_TYPE_ARRAY);
+} map2_t;
+
+extern map2_t map2 SEC(".maps");
+
+/* This should be the winning map definition, but we have no way of verifying,
+ * so we just make sure that it links and works without errors
+ */
+struct {
+	__uint(type, BPF_MAP_TYPE_ARRAY);
+	__type(key, int);
+	__type(value, int);
+	__uint(max_entries, 16);
+} map_weak __weak SEC(".maps");
+
+int output_first1;
+int output_second1;
+int output_weak1;
+
+SEC("raw_tp/sys_enter")
+int BPF_PROG(handler_enter1)
+{
+	/* update values with key = 1 */
+	int key = 1, val = 1;
+	struct my_key key_struct = { .x = 1 };
+	struct my_value val_struct = { .x = 1000 };
+
+	bpf_map_update_elem(&map1, &key_struct, &val_struct, 0);
+	bpf_map_update_elem(&map2, &key, &val, 0);
+	bpf_map_update_elem(&map_weak, &key, &val, 0);
+
+	return 0;
+}
+
+SEC("raw_tp/sys_exit")
+int BPF_PROG(handler_exit1)
+{
+	/* lookup values with key = 2, set in another file */
+	int key = 2, *val;
+	struct my_key key_struct = { .x = 2 };
+	struct my_value *value_struct;
+
+	value_struct = bpf_map_lookup_elem(&map1, &key_struct);
+	if (value_struct)
+		output_first1 = value_struct->x;
+
+	val = bpf_map_lookup_elem(&map2, &key);
+	if (val)
+		output_second1 = *val;
+
+	val = bpf_map_lookup_elem(&map_weak, &key);
+	if (val)
+		output_weak1 = *val;
+	
+	return 0;
+}
+
+char LICENSE[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/progs/linked_maps2.c b/tools/testing/selftests/bpf/progs/linked_maps2.c
new file mode 100644
index 000000000000..0693687474ed
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/linked_maps2.c
@@ -0,0 +1,76 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021 Facebook */
+
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+/* modifiers and typedefs are ignored when comparing key/value types */
+typedef struct my_key { long x; } key_type;
+typedef struct my_value { long x; } value_type;
+
+extern struct {
+	__uint(max_entries, 16);
+	__type(key, key_type);
+	__type(value, value_type);
+	__uint(type, BPF_MAP_TYPE_HASH);
+} map1 SEC(".maps");
+
+struct {
+	__uint(type, BPF_MAP_TYPE_ARRAY);
+	__type(key, int);
+	__type(value, int);
+	__uint(max_entries, 8);
+} map2 SEC(".maps");
+
+/* this definition will lose, but it has to exactly match the winner */
+struct {
+	__uint(type, BPF_MAP_TYPE_ARRAY);
+	__type(key, int);
+	__type(value, int);
+	__uint(max_entries, 16);
+} map_weak __weak SEC(".maps");
+
+int output_first2;
+int output_second2;
+int output_weak2;
+
+SEC("raw_tp/sys_enter")
+int BPF_PROG(handler_enter2)
+{
+	/* update values with key = 2 */
+	int key = 2, val = 2;
+	key_type key_struct = { .x = 2 };
+	value_type val_struct = { .x = 2000 };
+
+	bpf_map_update_elem(&map1, &key_struct, &val_struct, 0);
+	bpf_map_update_elem(&map2, &key, &val, 0);
+	bpf_map_update_elem(&map_weak, &key, &val, 0);
+
+	return 0;
+}
+
+SEC("raw_tp/sys_exit")
+int BPF_PROG(handler_exit2)
+{
+	/* lookup values with key = 1, set in another file */
+	int key = 1, *val;
+	key_type key_struct = { .x = 1 };
+	value_type *value_struct;
+
+	value_struct = bpf_map_lookup_elem(&map1, &key_struct);
+	if (value_struct)
+		output_first2 = value_struct->x;
+
+	val = bpf_map_lookup_elem(&map2, &key);
+	if (val)
+		output_second2 = *val;
+
+	val = bpf_map_lookup_elem(&map_weak, &key);
+	if (val)
+		output_weak2 = *val;
+
+	return 0;
+}
+
+char LICENSE[] SEC("license") = "GPL";