[PATCH v1 0/5] Enable BPF skeletons by default

[Ian Rogers <irogers@google.com>]

Enable BPF skeletons by default but warn don't fail if they can't be
supported. This was the intended behavior for Linux 6.4 but it caused
an issue captured in this thread:
https://lore.kernel.org/lkml/20230503211801.897735-1-acme@kernel.org/

This issue isn't repeated here as the previous issue related to
generating vmlinux.h, which is no longer performed by default as a
checked-in vmlinux.h is used instead.

Unlike with those changes, the BUILD_BPF_SKEL is kept and setting it
to 0 disables BPF skeletons. Also, rather than fail the build due to a
missed dependency, dependencies are checked and BPF skeletons disabled
if they aren't present.

Some related commits:
b7a2d774c9c5 perf build: Add ability to build with a generated vmlinux.h
a887466562b4 perf bpf skels: Stop using vmlinux.h generated from BTF, use subset of used structs + CO-RE
a2af0f6b8ef7 perf build: Add system include paths to BPF builds
5be6cecda080 perf bpf skels: Make vmlinux.h use bpf.h and perf_event.h in source directory
9a2d5178b9d5 Revert "perf build: Make BUILD_BPF_SKEL default, rename to NO_BPF_SKEL"
a887466562b4 perf bpf skels: Stop using vmlinux.h generated from BTF, use subset of used structs + CO-RE
1d7966547e11 perf build: Add warning for when vmlinux.h generation fails
a980755beb5a perf build: Make BUILD_BPF_SKEL default, rename to NO_BPF_SKEL

Ian Rogers (5):
  perf version: Add status of bpf skeletons
  perf build: Default BUILD_BPF_SKEL, warn/disable for missing deps
  perf test: Update build test for changed BPF skeleton defaults
  perf test: Ensure EXTRA_TESTS is covered in build test
  perf test: Detect off-cpu support from build options

 tools/perf/Makefile.config              | 78 ++++++++++++++++---------
 tools/perf/Makefile.perf                |  8 +--
 tools/perf/builtin-version.c            |  1 +
 tools/perf/tests/make                   |  7 ++-
 tools/perf/tests/shell/record_offcpu.sh |  2 +-
 5 files changed, 59 insertions(+), 37 deletions(-)

-- 
2.42.0.459.ge4e396fd5e-goog