[tools/perf] perf test LLVM failure on 4.9

[Wangnan (F)]

On 2018/1/23 20:37, Pintu Kumar wrote:
> Hi All,
>
> I am verifying all perf tests on Ubuntu-16 x86-64 platform using the
> kernel version 4.9.20.
> I have installed several others packages including: clang, llvm
>
> But, when I run 'perf test' I get some FAILURE.
> Specially, 'perf test LLVM' is failing.
>
> Please check the below error logs:
>
> ----------------------------------------------------
> # perf test LLVM
> 35: Test LLVM searching and compiling                        :
> 35.1: Basic BPF llvm compiling test                          : FAILED!
> 35.2: Test kbuild searching                                  : Skip
> 35.3: Compile source for BPF prologue generation test        : Skip
> 35.4: Compile source for BPF relocation test                 : Skip
> ----------------------------------------------------
>
> When I run with -v I get this:
>
> -----------------------------------------------------
> # perf test -v LLVM
> 35: Test LLVM searching and compiling                        :
> 35.1: Basic BPF llvm compiling test                          :
> --- start ---
> test child forked, pid 3304
> Unablt to get kernel version from uname '4.9-xxxx-amd-x86-64'
> WARNING:        unable to get correct kernel building directory.
> Hint:   Set correct kbuild directory using 'kbuild-dir' option in [llvm]
>          section of ~/.perfconfig or set it to "" to suppress kbuild
>          detection.
>
> Unablt to get kernel version from uname '4.9-xxxx-amd-x86-64'
>
>
> int _version SEC("version") = LINUX_VERSION_CODE;
> ' | $CLANG_EXEC -D__KERNEL__ -D__NR_CPUS__=$NR_CPUS
> -DLINUX_VERSION_CODE=$LINUX_VERSION_CODE $CLANG_OPTIONS
> $KERNEL_INC_OPTIONS -Wno-unused-value -Wno-pointer-sign
> -working-directory $WORKING_DIR -c "$CLANG_SOURCE" -target bpf -O2 -o
> -
> libbpf: 2129190-4a0 doesn't provide kernel version
> Failed to parse test case 'Basic BPF llvm compiling test'
> test child finished with -1
> ---- end ----
> Test LLVM searching and compiling subtest 0: FAILED!
> -----------------------------------------------------
>
>
> Basic BPF LLVM compiling test is failing.
> It reports that bpf could not able to read the kernel version from uname.
> Is it because of this that 'perf test LLVM' is failing ?
>
> My uname says:
> 4.9-xxxx-amd-x86-64

'perf test LLVM' requires a well formed uname string (%d.%d.%d). Please see
tools/perf/fetch_kernel_version . If your distro uses another method to 
report
kernel version number (from your uname string, sublevel can't be 
determined),
please help us improve that function like what we have done for ubuntu
(checking /proc/version_signature).


> My kernel version is: 4.9.20 (from Makefile)
>
> So, I dont think there is any problem with kernel version.
>
> If any body have come across this problem please let me know how to
> resolve this issue.
>
>
>
> Thank You!
>
> Regards,
> Pintu