This patch set switches pahole to use libbpf-provided BTF loading and encoding
APIs. This reduces pahole's own BTF encoding code, speeds up the process,
reduces amount of RAM needed for DWARF-to-BTF conversion. Also, pahole finally
gets support to generating BTF for cross-compiled ELF binaries with different
endianness (patch #8).
Additionally, patch #3 fixes previously missed problem with invalid array
index type generation.
Patches #4-7 are speeding up DWARF-to-BTF convertion/dedup pretty
significantly, saving overall about 9 seconds out of current 27 or so.
Patch #5 revamps how per-CPU BTF variables are emitted, eliminating repeated
and expensive looping over ELF symbols table. The critical detail that took
few hours of investigation is that when DW_AT_variable has
DW_AT_specification, variable address (to correlate with symbol's address) has
to be taken before specification is followed.
More details could be found in respective patches.
v1->v2:
- rebase on latest dwarves master and fix var->spec's address problem.
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Andrii Nakryiko (8):
btf_loader: use libbpf to load BTF
btf_encoder: use libbpf APIs to encode BTF type info
btf_encoder: fix emitting __ARRAY_SIZE_TYPE__ as index range type
btf_encoder: discard CUs after BTF encoding
btf_encoder: revamp how per-CPU variables are encoded
dwarf_loader: increase the size of lookup hash map
strings: use BTF's string APIs for strings management
btf_encoder: support cross-compiled ELF binaries with different
endianness
btf_encoder.c | 370 +++++++++++++++------------
btf_loader.c | 244 +++++++-----------
ctf_encoder.c | 2 +-
dwarf_loader.c | 2 +-
libbtf.c | 661 +++++++++++++++++++++----------------------------
libbtf.h | 41 ++-
libctf.c | 14 +-
libctf.h | 4 +-
pahole.c | 2 +-
strings.c | 91 +++----
strings.h | 32 +--
11 files changed, 645 insertions(+), 818 deletions(-)
--
2.24.1
