Default size of dedup table (16k) is good enough for most binaries, even
typical vmlinux images. But there are cases of binaries with huge amount
of BTF types (e.g., allyesconfig variants of kernel), which benefit from
having bigger dedup table size to lower amount of unnecessary hash
collisions. Tools like pahole, thus, can tune this parameter to reach
optimal performance.
This change also serves double purpose of allowing tests to force hash
collisions to test some corner cases, used in follow up patch.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The "ref_type_id" variable needs to be signed for the error handling
to work.
Fixes: d5caef5b5655 ("btf: add BTF types deduplication algorithm")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
* tools/libbpf: support bigger BTF data sizes
While it's understandable why kernel limits number of BTF types to 65535
and size of string section to 64KB, in libbpf as user-space library it's
too restrictive. E.g., pahole converting DWARF to BTF type information
for Linux kernel generates more than 3 million BTF types and more than
3MB of strings, before deduplication. So to allow btf__dedup() to do its
work, we need to be able to load bigger BTF sections using btf__new().
Singed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
* sync: latest libbpf changes from kernel
Syncing latest libbpf commits from kernel repository.
Baseline commit: 789f6bab849e04ea029c09b81dc8401dc0268cf9
Checkpoint commit: 5aab392c55c96f9bb26d9294f965f156a87ee81c
Andrii Nakryiko (1):
tools/libbpf: support bigger BTF data sizes
src/btf.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)
--
2.17.1
sync with latest bpf-next tree.
the include/linux/filter.h is created as libbpf.c tries
to use various insn define macros.
Signed-off-by: Yonghong Song <yhs@fb.com>
This initial commit added the following files
from bpf-next repository:
src:
<files from linux:tools/lib/bpf>
bpf.c bpf.h btf.c btf.h libbpf.c libbpf.h
libbpf_errno.c netlink.c nlattr.c nlattr.h
str_error.c str_error.h
include:
<files from linux:tools/include/uapi/linux>
uapi/linux/{bpf.h, btf.h}
<files from linux:tools/include/tools>
tools/libc_compat.h
The following files are also added:
include/linux/{err.h, kernel.h, list.h, overflow.h, types.h}
These files are customized headers to satisfy compilation.
Their original counterparts are at linux:tools/include/linux
directory.
Signed-off-by: Yonghong Song <yhs@fb.com>
