[PATCH 1/1] perf build: Require at least clang 16.0.6 to build BPF skeletons

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Howard reported problems using perf features that use BPF:

  perf $ clang -v
  Debian clang version 15.0.6
  Target: x86_64-pc-linux-gnu
  Thread model: posix
  InstalledDir: /bin
  Found candidate GCC installation: /bin/../lib/gcc/x86_64-linux-gnu/12
  Selected GCC installation: /bin/../lib/gcc/x86_64-linux-gnu/12
  Candidate multilib: .;@m64
  Selected multilib: .;@m64
  perf $ ./perf trace -e write --max-events=1
  libbpf: prog 'sys_enter_rename': BPF program load failed: Permission denied
  libbpf: prog 'sys_enter_rename': -- BEGIN PROG LOAD LOG --
  0: R1=ctx() R10=fp0

But it works with:

  perf $ clang -v
  Debian clang version 16.0.6 (15~deb12u1)
  Target: x86_64-pc-linux-gnu
  Thread model: posix
  InstalledDir: /bin
  Found candidate GCC installation: /bin/../lib/gcc/x86_64-linux-gnu/12
  Selected GCC installation: /bin/../lib/gcc/x86_64-linux-gnu/12
  Candidate multilib: .;@m64
  Selected multilib: .;@m64
  perf $ ./perf trace -e write --max-events=1
       0.000 ( 0.009 ms): gmain/1448 write(fd: 4, buf: \1\0\0\0\0\0\0\0, count: 8)                         = 8 (kworker/0:0-eve)
  perf $

So lets make that the required version, if you happen to have a slightly
older version where this work, please report so that we can adjust the
minimum required version.

Reported-by: Howard Chu <howardchu95@gmail.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alan Maguire <alan.maguire@oracle.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/Makefile.config | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
index 37e3eee2986e580a..4c1f75e326e2c1d2 100644
--- a/tools/perf/Makefile.config
+++ b/tools/perf/Makefile.config
@@ -705,8 +705,8 @@ ifeq ($(BUILD_BPF_SKEL),1)
     BUILD_BPF_SKEL := 0
   else
     CLANG_VERSION := $(shell $(CLANG) --version | head -1 | sed 's/.*clang version \([[:digit:]]\+.[[:digit:]]\+.[[:digit:]]\+\).*/\1/g')
-    ifeq ($(call version-lt3,$(CLANG_VERSION),12.0.1),1)
-      $(warning Warning: Disabled BPF skeletons as reliable BTF generation needs at least $(CLANG) version 12.0.1)
+    ifeq ($(call version-lt3,$(CLANG_VERSION),16.0.6),1)
+      $(warning Warning: Disabled BPF skeletons as at least $(CLANG) version 16.0.6 is reported to be a working setup with the current of BPF based perf features)
       BUILD_BPF_SKEL := 0
     endif
   endif
-- 
2.46.0