23543 Commits

Author SHA1 Message Date
Andrii Nakryiko
b0efc216f5 libbpf: Compile in PIC mode only for shared library case
Libbpf compiles .o's for static and shared library modes separately, so no
need to specify -fPIC for both. Keep it only for shared library mode.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200929220604.833631-3-andriin@fb.com
2020-09-29 17:05:31 -07:00
Andrii Nakryiko
0a62291d69 libbpf: Compile libbpf under -O2 level by default and catch extra warnings
For some reason compiler doesn't complain about uninitialized variable, fixed
in previous patch, if libbpf is compiled without -O2 optimization level. So do
compile it with -O2 and never let similar issue slip by again. -Wall is added
unconditionally, so no need to specify it again.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200929220604.833631-2-andriin@fb.com
2020-09-29 17:05:31 -07:00
Andrii Nakryiko
3343391345 libbpf: Fix uninitialized variable in btf_parse_type_sec
Fix obvious unitialized variable use that wasn't reported by compiler. libbpf
Makefile changes to catch such errors are added separately.

Fixes: 3289959b97ca ("libbpf: Support BTF loading and raw data output in both endianness")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200929220604.833631-1-andriin@fb.com
2020-09-29 17:05:31 -07:00
Ilya Leoshkevich
6458bde368 selftests/bpf: Fix endianness issues in sk_lookup/ctx_narrow_access
This test makes a lot of narrow load checks while assuming little
endian architecture, and therefore fails on s390.

Fix by introducing LSB and LSW macros and using them to perform narrow
loads.

Fixes: 0ab5539f8584 ("selftests/bpf: Tests for BPF_SK_LOOKUP attach point")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200929201814.44360-1-iii@linux.ibm.com
2020-09-29 16:28:34 -07:00
Arnaldo Carvalho de Melo
9012e3dda2 perf trace beauty: Add script to autogenerate mremap's flags args string/id table
It'll also conditionally generate the defines, so that if we don't have
those when building a new tool tarball in an older systems, we get
those, and we need them sometimes in the actual scnprintf routine, such
as when checking if a flags means we have an extra arg, like with
MREMAP_FIXED.

  $ tools/perf/trace/beauty/mremap_flags.sh
  static const char *mremap_flags[] = {
  	[ilog2(1) + 1] = "MAYMOVE",
  #ifndef MREMAP_MAYMOVE
  #define MREMAP_MAYMOVE 1
  #endif
  	[ilog2(2) + 1] = "FIXED",
  #ifndef MREMAP_FIXED
  #define MREMAP_FIXED 2
  #endif
  	[ilog2(4) + 1] = "DONTUNMAP",
  #ifndef MREMAP_DONTUNMAP
  #define MREMAP_DONTUNMAP 4
  #endif
  };
  $

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-09-29 18:07:27 -03:00
John Fastabend
c810b31ecb bpf, selftests: Fix warning in snprintf_btf where system() call unchecked
On my systems system() calls are marked with warn_unused_result
apparently. So without error checking we get this warning,

./prog_tests/snprintf_btf.c:30:9: warning: ignoring return value
   of ‘system’, declared with attribute warn_unused_result[-Wunused-result]

Also it seems like a good idea to check the return value anyways
to ensure ping exists even if its seems unlikely.

Fixes: 076a95f5aff2c ("selftests/bpf: Add bpf_snprintf_btf helper tests")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/160141006897.25201.12095049414156293265.stgit@john-Precision-5820-Tower
2020-09-29 13:21:23 -07:00
Toke Høiland-Jørgensen
bee4b7e626 selftests: Add selftest for disallowing modify_return attachment to freplace
This adds a selftest that ensures that modify_return tracing programs
cannot be attached to freplace programs. The security_ prefix is added to
the freplace program because that would otherwise let it pass the check for
modify_return.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/160138355713.48470.3811074984255709369.stgit@toke.dk
2020-09-29 13:09:24 -07:00
Jiri Olsa
17d3f38675 selftests/bpf: Adding test for arg dereference in extension trace
Adding test that setup following program:

  SEC("classifier/test_pkt_md_access")
  int test_pkt_md_access(struct __sk_buff *skb)

with its extension:

  SEC("freplace/test_pkt_md_access")
  int test_pkt_md_access_new(struct __sk_buff *skb)

and tracing that extension with:

  SEC("fentry/test_pkt_md_access_new")
  int BPF_PROG(fentry, struct sk_buff *skb)

The test verifies that the tracing program can
dereference skb argument properly.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/160138355603.48470.9072073357530773228.stgit@toke.dk
2020-09-29 13:09:24 -07:00
Toke Høiland-Jørgensen
f6429476c2 selftests: Add test for multiple attachments of freplace program
This adds a selftest for attaching an freplace program to multiple targets
simultaneously.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/160138355497.48470.17568077161540217107.stgit@toke.dk
2020-09-29 13:09:24 -07:00
Toke Høiland-Jørgensen
a535909142 libbpf: Add support for freplace attachment in bpf_link_create
This adds support for supplying a target btf ID for the bpf_link_create()
operation, and adds a new bpf_program__attach_freplace() high-level API for
attaching freplace functions with a target.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/160138355387.48470.18026176785351166890.stgit@toke.dk
2020-09-29 13:09:24 -07:00
Toke Høiland-Jørgensen
4a1e7c0c63 bpf: Support attaching freplace programs to multiple attach points
This enables support for attaching freplace programs to multiple attach
points. It does this by amending the UAPI for bpf_link_Create with a target
btf ID that can be used to supply the new attachment point along with the
target program fd. The target must be compatible with the target that was
supplied at program load time.

The implementation reuses the checks that were factored out of
check_attach_btf_id() to ensure compatibility between the BTF types of the
old and new attachment. If these match, a new bpf_tracing_link will be
created for the new attach target, allowing multiple attachments to
co-exist simultaneously.

The code could theoretically support multiple-attach of other types of
tracing programs as well, but since I don't have a use case for any of
those, there is no API support for doing so.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/160138355169.48470.17165680973640685368.stgit@toke.dk
2020-09-29 13:09:24 -07:00
Andrii Nakryiko
ed9cf248b9 selftests/bpf: Test BTF's handling of endianness
Add selftests juggling endianness back and forth to validate BTF's handling of
endianness convertions internally.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200929043046.1324350-4-andriin@fb.com
2020-09-29 12:21:23 -07:00
Andrii Nakryiko
3289959b97 libbpf: Support BTF loading and raw data output in both endianness
Teach BTF to recognized wrong endianness and transparently convert it
internally to host endianness. Original endianness of BTF will be preserved
and used during btf__get_raw_data() to convert resulting raw data to the same
endianness and a source raw_data. This means that little-endian host can parse
big-endian BTF with no issues, all the type data will be presented to the
client application in native endianness, but when it's time for emitting BTF
to persist it in a file (e.g., after BTF deduplication), original non-native
endianness will be preserved and stored.

It's possible to query original endianness of BTF data with new
btf__endianness() API. It's also possible to override desired output
endianness with btf__set_endianness(), so that if application needs to load,
say, big-endian BTF and store it as little-endian BTF, it's possible to
manually override this. If btf__set_endianness() was used to change
endianness, btf__endianness() will reflect overridden endianness.

Given there are no known use cases for supporting cross-endianness for
.BTF.ext, loading .BTF.ext in non-native endianness is not supported.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200929043046.1324350-3-andriin@fb.com
2020-09-29 12:21:23 -07:00
Andrii Nakryiko
22ba363516 selftests/bpf: Move and extend ASSERT_xxx() testing macros
Move existing ASSERT_xxx() macros out of btf_write selftest into test_progs.h
to use across all selftests. Also expand a set of macros for typical cases.

Now there are the following macros:
  - ASSERT_EQ() -- check for equality of two integers;
  - ASSERT_STREQ() -- check for equality of two C strings;
  - ASSERT_OK() -- check for successful (zero) return result;
  - ASSERT_ERR() -- check for unsuccessful (non-zero) return result;
  - ASSERT_NULL() -- check for NULL pointer;
  - ASSERT_OK_PTR() -- check for a valid pointer;
  - ASSERT_ERR_PTR() -- check for NULL or negative error encoded in a pointer.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200929043046.1324350-2-andriin@fb.com
2020-09-29 12:21:23 -07:00
Toke Høiland-Jørgensen
f970cbcdcd selftests: Make sure all 'skel' variables are declared static
If programs in prog_tests using skeletons declare the 'skel' variable as
global but not static, that will lead to linker errors on the final link of
the prog_tests binary due to duplicate symbols. Fix a few instances of this.

Fixes: b18c1f0aa477 ("bpf: selftest: Adapt sock_fields test to use skel and global variables")
Fixes: 9a856cae2217 ("bpf: selftest: Add test_btf_skc_cls_ingress")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200929123026.46751-1-toke@redhat.com
2020-09-29 11:43:43 -07:00
Toke Høiland-Jørgensen
d2197c7ff1 selftests/bpf_iter: Don't fail test due to missing __builtin_btf_type_id
The new test for task iteration in bpf_iter checks (in do_btf_read()) if it
should be skipped due to missing __builtin_btf_type_id. However, this
'skip' verdict is not propagated to the caller, so the parent test will
still fail. Fix this by also skipping the rest of the parent test if the
skip condition was reached.

Fixes: b72091bd4ee4 ("selftests/bpf: Add test for bpf_seq_printf_btf helper")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20200929123004.46694-1-toke@redhat.com
2020-09-29 11:18:19 -07:00
Alan Maguire
cfe77683b8 selftests/bpf: Ensure snprintf_btf/bpf_iter tests compatibility with old vmlinux.h
Andrii reports that bpf selftests relying on "struct btf_ptr" and BTF_F_*
values will not build as vmlinux.h for older kernels will not include
"struct btf_ptr" or the BTF_F_* enum values.  Undefine and redefine
them to work around this.

Fixes: b72091bd4ee4 ("selftests/bpf: Add test for bpf_seq_printf_btf helper")
Fixes: 076a95f5aff2 ("selftests/bpf: Add bpf_snprintf_btf helper tests")
Reported-by: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/1601379151-21449-3-git-send-email-alan.maguire@oracle.com
2020-09-29 11:10:48 -07:00
Alan Maguire
96c48058db selftests/bpf: Fix unused-result warning in snprintf_btf.c
Daniel reports:

+    system("ping -c 1 127.0.0.1 > /dev/null");

This generates the following new warning when compiling BPF selftests:

  [...]
  EXT-OBJ  [test_progs] cgroup_helpers.o
  EXT-OBJ  [test_progs] trace_helpers.o
  EXT-OBJ  [test_progs] network_helpers.o
  EXT-OBJ  [test_progs] testing_helpers.o
  TEST-OBJ [test_progs] snprintf_btf.test.o
/root/bpf-next/tools/testing/selftests/bpf/prog_tests/snprintf_btf.c: In function ‘test_snprintf_btf’:
/root/bpf-next/tools/testing/selftests/bpf/prog_tests/snprintf_btf.c:30:2: warning: ignoring return value of ‘system’, declared with attribute warn_unused_result [-Wunused-result]
  system("ping -c 1 127.0.0.1 > /dev/null");
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  [...]

Fixes: 076a95f5aff2 ("selftests/bpf: Add bpf_snprintf_btf helper tests")
Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601379151-21449-2-git-send-email-alan.maguire@oracle.com
2020-09-29 11:10:48 -07:00
Arnaldo Carvalho de Melo
d758d5d474 perf tools: Separate the checking of headers only used to build beautification tables
Some headers are not used in building the tools directly, but instead to
generate tables that then gets source code included to do id->string and
string->id lookups for things like syscall flags and commands.

We were adding it directly to tools/include/ and this sometimes gets in
the way of building using system headers, lets untangle this a bit.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-09-29 08:56:38 -03:00
John Fastabend
00e8c44a14 bpf, selftests: Fix cast to smaller integer type 'int' warning in raw_tp
Fix warning in bpf selftests,

progs/test_raw_tp_test_run.c:18:10: warning: cast to smaller integer type 'int' from 'struct task_struct *' [-Wpointer-to-int-cast]

Change int type cast to long to fix. Discovered with gcc-9 and llvm-11+
where llvm was recent main branch.

Fixes: 09d8ad16885ee ("selftests/bpf: Add raw_tp_test_run")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/160134424745.11199.13841922833336698133.stgit@john-Precision-5820-Tower
2020-09-28 21:33:38 -07:00
Andrii Nakryiko
9141f75a32 selftests/bpf: Test BTF writing APIs
Add selftests for BTF writer APIs.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200929020533.711288-4-andriin@fb.com
2020-09-28 19:17:13 -07:00
Andrii Nakryiko
f86ed050bc libbpf: Add btf__str_by_offset() as a more generic variant of name_by_offset
BTF strings are used not just for names, they can be arbitrary strings used
for CO-RE relocations, line/func infos, etc. Thus "name_by_offset" terminology
is too specific and might be misleading. Instead, introduce
btf__str_by_offset() API which uses generic string terminology.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200929020533.711288-3-andriin@fb.com
2020-09-28 19:17:13 -07:00
Andrii Nakryiko
4a3b33f857 libbpf: Add BTF writing APIs
Add APIs for appending new BTF types at the end of BTF object.

Each BTF kind has either one API of the form btf__add_<kind>(). For types
that have variable amount of additional items (struct/union, enum, func_proto,
datasec), additional API is provided to emit each such item. E.g., for
emitting a struct, one would use the following sequence of API calls:

btf__add_struct(...);
btf__add_field(...);
...
btf__add_field(...);

Each btf__add_field() will ensure that the last BTF type is of STRUCT or
UNION kind and will automatically increment that type's vlen field.

All the strings are provided as C strings (const char *), not a string offset.
This significantly improves usability of BTF writer APIs. All such strings
will be automatically appended to string section or existing string will be
re-used, if such string was already added previously.

Each API attempts to do all the reasonable validations, like enforcing
non-empty names for entities with required names, proper value bounds, various
bit offset restrictions, etc.

Type ID validation is minimal because it's possible to emit a type that refers
to type that will be emitted later, so libbpf has no way to enforce such
cases. User must be careful to properly emit all the necessary types and
specify type IDs that will be valid in the finally generated BTF.

Each of btf__add_<kind>() APIs return new type ID on success or negative
value on error. APIs like btf__add_field() that emit additional items
return zero on success and negative value on error.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200929020533.711288-2-andriin@fb.com
2020-09-28 19:17:13 -07:00
Alan Maguire
b72091bd4e selftests/bpf: Add test for bpf_seq_printf_btf helper
Add a test verifying iterating over tasks and displaying BTF
representation of task_struct succeeds.

Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601292670-1616-9-git-send-email-alan.maguire@oracle.com
2020-09-28 18:26:58 -07:00
Alan Maguire
eb411377ae bpf: Add bpf_seq_printf_btf helper
A helper is added to allow seq file writing of kernel data
structures using vmlinux BTF.  Its signature is

long bpf_seq_printf_btf(struct seq_file *m, struct btf_ptr *ptr,
                        u32 btf_ptr_size, u64 flags);

Flags and struct btf_ptr definitions/use are identical to the
bpf_snprintf_btf helper, and the helper returns 0 on success
or a negative error value.

Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601292670-1616-8-git-send-email-alan.maguire@oracle.com
2020-09-28 18:26:58 -07:00
Alan Maguire
eb58bbf2e5 selftests/bpf: Fix overflow tests to reflect iter size increase
bpf iter size increase to PAGE_SIZE << 3 means overflow tests assuming
page size need to be bumped also.

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601292670-1616-7-git-send-email-alan.maguire@oracle.com
2020-09-28 18:26:58 -07:00
Alan Maguire
076a95f5af selftests/bpf: Add bpf_snprintf_btf helper tests
Tests verifying snprintf()ing of various data structures,
flags combinations using a tp_btf program. Tests are skipped
if __builtin_btf_type_id is not available to retrieve BTF
type ids.

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601292670-1616-5-git-send-email-alan.maguire@oracle.com
2020-09-28 18:26:58 -07:00
Alan Maguire
c4d0bfb450 bpf: Add bpf_snprintf_btf helper
A helper is added to support tracing kernel type information in BPF
using the BPF Type Format (BTF).  Its signature is

long bpf_snprintf_btf(char *str, u32 str_size, struct btf_ptr *ptr,
		      u32 btf_ptr_size, u64 flags);

struct btf_ptr * specifies

- a pointer to the data to be traced
- the BTF id of the type of data pointed to
- a flags field is provided for future use; these flags
  are not to be confused with the BTF_F_* flags
  below that control how the btf_ptr is displayed; the
  flags member of the struct btf_ptr may be used to
  disambiguate types in kernel versus module BTF, etc;
  the main distinction is the flags relate to the type
  and information needed in identifying it; not how it
  is displayed.

For example a BPF program with a struct sk_buff *skb
could do the following:

	static struct btf_ptr b = { };

	b.ptr = skb;
	b.type_id = __builtin_btf_type_id(struct sk_buff, 1);
	bpf_snprintf_btf(str, sizeof(str), &b, sizeof(b), 0, 0);

Default output looks like this:

(struct sk_buff){
 .transport_header = (__u16)65535,
 .mac_header = (__u16)65535,
 .end = (sk_buff_data_t)192,
 .head = (unsigned char *)0x000000007524fd8b,
 .data = (unsigned char *)0x000000007524fd8b,
 .truesize = (unsigned int)768,
 .users = (refcount_t){
  .refs = (atomic_t){
   .counter = (int)1,
  },
 },
}

Flags modifying display are as follows:

- BTF_F_COMPACT:	no formatting around type information
- BTF_F_NONAME:		no struct/union member names/types
- BTF_F_PTR_RAW:	show raw (unobfuscated) pointer values;
			equivalent to %px.
- BTF_F_ZERO:		show zero-valued struct/union members;
			they are not displayed by default

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601292670-1616-4-git-send-email-alan.maguire@oracle.com
2020-09-28 18:26:58 -07:00
Andrii Nakryiko
a871b04310 libbpf: Add btf__new_empty() to create an empty BTF object
Add an ability to create an empty BTF object from scratch. This is going to be
used by pahole for BTF encoding. And also by selftest for convenient creation
of BTF objects.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200926011357.2366158-7-andriin@fb.com
2020-09-28 17:27:32 -07:00
Andrii Nakryiko
919d2b1dbb libbpf: Allow modification of BTF and add btf__add_str API
Allow internal BTF representation to switch from default read-only mode, in
which raw BTF data is a single non-modifiable block of memory with BTF header,
types, and strings layed out sequentially and contiguously in memory, into
a writable representation with types and strings data split out into separate
memory regions, that can be dynamically expanded.

Such writable internal representation is transparent to users of libbpf APIs,
but allows to append new types and strings at the end of BTF, which is
a typical use case when generating BTF programmatically. All the basic
guarantees of BTF types and strings layout is preserved, i.e., user can get
`struct btf_type *` pointer and read it directly. Such btf_type pointers might
be invalidated if BTF is modified, so some care is required in such mixed
read/write scenarios.

Switch from read-only to writable configuration happens automatically the
first time when user attempts to modify BTF by either adding a new type or new
string. It is still possible to get raw BTF data, which is a single piece of
memory that can be persisted in ELF section or into a file as raw BTF. Such
raw data memory is also still owned by BTF and will be freed either when BTF
object is freed or if another modification to BTF happens, as any modification
invalidates BTF raw representation.

This patch adds the first two BTF manipulation APIs: btf__add_str(), which
allows to add arbitrary strings to BTF string section, and btf__find_str()
which allows to find existing string offset, but not add it if it's missing.
All the added strings are automatically deduplicated. This is achieved by
maintaining an additional string lookup index for all unique strings. Such
index is built when BTF is switched to modifiable mode. If at that time BTF
strings section contained duplicate strings, they are not de-duplicated. This
is done specifically to not modify the existing content of BTF (types, their
string offsets, etc), which can cause confusion and is especially important
property if there is struct btf_ext associated with struct btf. By following
this "imperfect deduplication" process, btf_ext is kept consitent and correct.
If deduplication of strings is necessary, it can be forced by doing BTF
deduplication, at which point all the strings will be eagerly deduplicated and
all string offsets both in struct btf and struct btf_ext will be updated.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200926011357.2366158-6-andriin@fb.com
2020-09-28 17:27:31 -07:00
Andrii Nakryiko
7d9c71e10b libbpf: Extract generic string hashing function for reuse
Calculating a hash of zero-terminated string is a common need when using
hashmap, so extract it for reuse.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200926011357.2366158-5-andriin@fb.com
2020-09-28 17:27:31 -07:00
Andrii Nakryiko
192f5a1fe6 libbpf: Generalize common logic for managing dynamically-sized arrays
Managing dynamically-sized array is a common, but not trivial functionality,
which significant amount of logic and code to implement properly. So instead
of re-implementing it all the time, extract it into a helper function ans
reuse.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200926011357.2366158-4-andriin@fb.com
2020-09-28 17:27:31 -07:00
Andrii Nakryiko
b86042478f libbpf: Remove assumption of single contiguous memory for BTF data
Refactor internals of struct btf to remove assumptions that BTF header, type
data, and string data are layed out contiguously in a memory in a single
memory allocation. Now we have three separate pointers pointing to the start
of each respective are: header, types, strings. In the next patches, these
pointers will be re-assigned to point to independently allocated memory areas,
if BTF needs to be modified.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200926011357.2366158-3-andriin@fb.com
2020-09-28 17:27:31 -07:00
Andrii Nakryiko
740e69c3c5 libbpf: Refactor internals of BTF type index
Refactor implementation of internal BTF type index to not use direct pointers.
Instead it uses offset relative to the start of types data section. This
allows for types data to be reallocatable, enabling implementation of
modifiable BTF.

As now getting type by ID has an extra indirection step, convert all internal
type lookups to a new helper btf_type_id(), that returns non-const pointer to
a type by its ID.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200926011357.2366158-2-andriin@fb.com
2020-09-28 17:27:31 -07:00
Toke Høiland-Jørgensen
b000def2e0 selftests: Remove fmod_ret from test_overhead
The test_overhead prog_test included an fmod_ret program that attached to
__set_task_comm() in the kernel. However, this function was never listed as
allowed for return modification, so this only worked because of the
verifier skipping tests when a trampoline already existed for the attach
point. Now that the verifier checks have been fixed, remove fmod_ret from
the test so it works again.

Fixes: 4eaf0b5c5e04 ("selftest/bpf: Fmod_ret prog and implement test_overhead as part of bench")
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2020-09-28 17:20:28 -07:00
Lorenz Bauer
5b87adc3ce selftest: bpf: Test copying a sockmap and sockhash
Since we can now call map_update_elem(sockmap) from bpf_iter context
it's possible to copy a sockmap or sockhash in the kernel. Add a
selftest which exercises this.

Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200928090805.23343-5-lmb@cloudflare.com
2020-09-28 16:48:02 -07:00
Lorenz Bauer
2787031733 selftests: bpf: Remove shared header from sockmap iter test
The shared header to define SOCKMAP_MAX_ENTRIES is a bit overkill.
Dynamically allocate the sock_fd array based on bpf_map__max_entries
instead.

Suggested-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200928090805.23343-4-lmb@cloudflare.com
2020-09-28 16:48:02 -07:00
Lorenz Bauer
26c3270ddb selftests: bpf: Add helper to compare socket cookies
We compare socket cookies to ensure that insertion into a sockmap worked.
Pull this out into a helper function for use in other tests.

Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200928090805.23343-3-lmb@cloudflare.com
2020-09-28 16:47:58 -07:00
Song Liu
09d8ad1688 selftests/bpf: Add raw_tp_test_run
This test runs test_run for raw_tracepoint program. The test covers ctx
input, retval output, and running on correct cpu.

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200925205432.1777-4-songliubraving@fb.com
2020-09-28 21:52:36 +02:00
Song Liu
88f7fe7233 libbpf: Support test run of raw tracepoint programs
Add bpf_prog_test_run_opts() with support of new fields in bpf_attr.test,
namely, flags and cpu. Also extend _opts operations to support outputs via
opts.

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200925205432.1777-3-songliubraving@fb.com
2020-09-28 21:52:36 +02:00
Song Liu
1b4d60ec16 bpf: Enable BPF_PROG_TEST_RUN for raw_tracepoint
Add .test_run for raw_tracepoint. Also, introduce a new feature that runs
the target program on a specific CPU. This is achieved by a new flag in
bpf_attr.test, BPF_F_TEST_RUN_ON_CPU. When this flag is set, the program
is triggered on cpu with id bpf_attr.test.cpu. This feature is needed for
BPF programs that handle perf_event and other percpu resources, as the
program can access these resource locally.

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200925205432.1777-2-songliubraving@fb.com
2020-09-28 21:52:36 +02:00
Jakub Kicinski
8c4cf4bc3e selftests: net: add a test for static UDP tunnel ports
Check UDP_TUNNEL_NIC_INFO_STATIC_IANA_VXLAN works as expected.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-28 12:50:12 -07:00
Jakub Kicinski
53db3e53e2 selftests: net: add a test for shared UDP tunnel info tables
Add a test run of checks validating the shared UDP tunnel port
tables function as we expect.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-28 12:50:12 -07:00
Arnaldo Carvalho de Melo
717d182e41 Merge remote-tracking branch 'torvalds/master' into perf/core
To pick up fixes and get v5.10 development in sync with the main kernel
sources.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-09-28 15:44:52 -03:00
Ian Rogers
a55b7bb1c1 perf test: Fix msan uninitialized use.
Ensure 'st' is initialized before an error branch is taken.
Fixes test "67: Parse and process metrics" with LLVM msan:

  ==6757==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0x5570edae947d in rblist__exit tools/perf/util/rblist.c:114:2
    #1 0x5570edb1c6e8 in runtime_stat__exit tools/perf/util/stat-shadow.c:141:2
    #2 0x5570ed92cfae in __compute_metric tools/perf/tests/parse-metric.c:187:2
    #3 0x5570ed92cb74 in compute_metric tools/perf/tests/parse-metric.c:196:9
    #4 0x5570ed92c6d8 in test_recursion_fail tools/perf/tests/parse-metric.c:318:2
    #5 0x5570ed92b8c8 in test__parse_metric tools/perf/tests/parse-metric.c:356:2
    #6 0x5570ed8de8c1 in run_test tools/perf/tests/builtin-test.c:410:9
    #7 0x5570ed8ddadf in test_and_print tools/perf/tests/builtin-test.c:440:9
    #8 0x5570ed8dca04 in __cmd_test tools/perf/tests/builtin-test.c:661:4
    #9 0x5570ed8dbc07 in cmd_test tools/perf/tests/builtin-test.c:807:9
    #10 0x5570ed7326cc in run_builtin tools/perf/perf.c:313:11
    #11 0x5570ed731639 in handle_internal_command tools/perf/perf.c:365:8
    #12 0x5570ed7323cd in run_argv tools/perf/perf.c:409:2
    #13 0x5570ed731076 in main tools/perf/perf.c:539:3

Fixes: commit f5a56570a3f2 ("perf test: Fix memory leaks in parse-metric test")
Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: clang-built-linux@googlegroups.com
Link: http://lore.kernel.org/lkml/20200923210655.4143682-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-09-28 09:24:01 -03:00
Ian Rogers
aa98d8482c perf parse-events: Reduce casts around bp_addr
perf_event_attr bp_addr is a u64. parse-events.y parses it as a u64, but
casts it to a void* and then parse-events.c casts it back to a u64.
Rather than all the casts, change the type of the address to be a u64.

This removes an issue noted in:

  https://lore.kernel.org/lkml/20200903184359.GC3495158@kernel.org/

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200925003903.561568-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-09-28 09:22:39 -03:00
Namhyung Kim
40b74c30ff perf test: Add expand cgroup event test
It'll expand given events for cgroups A, B and C.

  $ perf test -v expansion
  69: Event expansion for cgroups                      :
  --- start ---
  test child forked, pid 983140
  metric expr 1 / IPC for CPI
  metric expr instructions / cycles for IPC
  found event instructions
  found event cycles
  adding {instructions,cycles}:W
  copying metric event for cgroup 'A': instructions (idx=0)
  copying metric event for cgroup 'B': instructions (idx=0)
  copying metric event for cgroup 'C': instructions (idx=0)
  test child finished with 0
  ---- end ----
  Event expansion for cgroups: Ok

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200924124455.336326-6-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-09-28 09:21:05 -03:00
Namhyung Kim
89fb1ca2ab perf tools: Allow creation of cgroup without open
This is a preparation for a test case of expanding events for multiple
cgroups.  Instead of using real system cgroup, the test will use fake
cgroups so it needs a way to have them without a open file descriptor.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200924124455.336326-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-09-28 09:18:06 -03:00
Namhyung Kim
b214ba8c42 perf tools: Copy metric events properly when expand cgroups
The metricgroup__copy_metric_events() is to handle metrics events when
expanding event for cgroups.  As the metric events keep pointers to
evsel, it should be refreshed when events are cloned during the
operation.

The perf_stat__collect_metric_expr() is also called in case an event has
a metric directly.

During the copy, it references evsel by index as the evlist now has
cloned evsels for the given cgroup.

Also kernel test robot found an issue in the python module import so add
empty implementations of those two functions to fix it.

Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200924124455.336326-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-09-28 09:16:21 -03:00
Namhyung Kim
d1c5a0e86a perf stat: Add --for-each-cgroup option
The --for-each-cgroup option is a syntax sugar to monitor large number
of cgroups easily.  Current command line requires to list all the events
and cgroups even if users want to monitor same events for each cgroup.
This patch addresses that usage by copying given events for each cgroup
on user's behalf.

For instance, if they want to monitor 6 events for 200 cgroups each they
should write 1200 event names (with -e) AND 1200 cgroup names (with -G)
on the command line.  But with this change, they can just specify 6
events and 200 cgroups with a new option.

A simpler example below: It wants to measure 3 events for 2 cgroups ('A'
and 'B').  The result is that total 6 events are counted like below.

  $ perf stat -a -e cpu-clock,cycles,instructions --for-each-cgroup A,B sleep 1

   Performance counter stats for 'system wide':

              988.18 msec cpu-clock                 A #    0.987 CPUs utilized
       3,153,761,702      cycles                    A #    3.200 GHz                      (100.00%)
       8,067,769,847      instructions              A #    2.57  insn per cycle           (100.00%)
              982.71 msec cpu-clock                 B #    0.982 CPUs utilized
       3,136,093,298      cycles                    B #    3.182 GHz                      (99.99%)
       8,109,619,327      instructions              B #    2.58  insn per cycle           (99.99%)

         1.001228054 seconds time elapsed

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200924124455.336326-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-09-28 09:07:08 -03:00