linux/tools/lib
Andrii Nakryiko 68153bb2ff libbpf: Add BTF field iterator
Implement iterator-based type ID and string offset BTF field iterator.
This is used extensively in BTF-handling code and BPF linker code for
various sanity checks, rewriting IDs/offsets, etc. Currently this is
implemented as visitor pattern calling custom callbacks, which makes the
logic (especially in simple cases) unnecessarily obscure and harder to
follow.

Having equivalent functionality using iterator pattern makes for simpler
to understand and maintain code. As we add more code for BTF processing
logic in libbpf, it's best to switch to iterator pattern before adding
more callback-based code.

The idea for iterator-based implementation is to record offsets of
necessary fields within fixed btf_type parts (which should be iterated
just once), and, for kinds that have multiple members (based on vlen
field), record where in each member necessary fields are located.

Generic iteration code then just keeps track of last offset that was
returned and handles N members correctly. Return type is just u32
pointer, where NULL is returned when all relevant fields were already
iterated.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Alan Maguire <alan.maguire@oracle.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20240605001629.4061937-2-andrii@kernel.org
2024-06-05 16:54:26 +02:00
..
api tools api fs: Avoid reading whole file for a 1 byte bool 2023-11-30 19:25:19 -03:00
bpf libbpf: Add BTF field iterator 2024-06-05 16:54:26 +02:00
perf perf record: Fix comment misspellings 2024-04-26 22:13:10 -03:00
subcmd tools lib subcmd: Show parent options in help 2024-05-12 21:09:52 -03:00
symbol tools lib symbol: Add dependency test to install_headers 2022-12-14 11:16:12 -03:00
thermal tools/lib/thermal: Fix include path for libnl3 in pkg-config file. 2023-02-15 17:29:40 +01:00
argv_split.c
bitmap.c Bitmap patches for v6.0-rc1 2022-08-07 17:52:35 -07:00
ctype.c
find_bit.c tools: sync find_bit() implementation 2022-09-21 12:21:44 -07:00
hweight.c
list_sort.c
rbtree.c tools lib rbtree: pick some improvements from the kernel rbtree code 2024-05-08 08:41:27 -07:00
slab.c
str_error_r.c
string.c
vsprintf.c
zalloc.c