Hi, On Sun, Jul 9, 2023 at 8:38 PM Anh Tuan Phan <tuananhlfc@xxxxxxxxx> wrote: > > Hi Stanislav, > > I have updated the Documentation according to your suggestion. Please > see it in the below patch. Thanks! > > On 7/7/23 23:57, Stanislav Fomichev wrote: > > On 07/07, Anh Tuan Phan wrote: > >> > >> > >> On 7/7/23 01:16, Stanislav Fomichev wrote: > >>> On 07/06, Anh Tuan Phan wrote: > >>>> Update the Documentation to mention that some samples require pahole > >>>> v1.16 and kernel built with CONFIG_DEBUG_INFO_BTF=y > >>>> > >>>> Signed-off-by: Anh Tuan Phan <tuananhlfc@xxxxxxxxx> > >>>> --- > >>>> samples/bpf/README.rst | 7 +++++++ > >>>> 1 file changed, 7 insertions(+) > >>>> > >>>> diff --git a/samples/bpf/README.rst b/samples/bpf/README.rst > >>>> index 57f93edd1957..631592b83d60 100644 > >>>> --- a/samples/bpf/README.rst > >>>> +++ b/samples/bpf/README.rst > >>>> @@ -14,6 +14,9 @@ Compiling requires having installed: > >>>> Note that LLVM's tool 'llc' must support target 'bpf', list version > >>>> and supported targets with command: ``llc --version`` > >>>> > >>>> +Some samples require pahole version 1.16 as a dependency. See > >>>> +https://docs.kernel.org/bpf/bpf_devel_QA.html for reference. > >>>> + > >>> > >>> Any reason no to add pahole 1.16 to this section above? > >>>> Compiling requires having installed: > >>> * clang >= version 3.4.0 > >>> * llvm >= version 3.7.1 > >>> * pahole >= version 1.16 > >>> > >>> Although clang 3.4 probably won't get you anywhere these days. The > >>> whole README seems a bit outdated :-) > >>> > >> > >> Put pahole requirement as your idea is better, thanks for suggestion. > >> Will update it and clang version as well. For clang version, I think I > >> can update min version as 11.0.0 (reference from > >> https://www.kernel.org/doc/html/next/process/changes.html). Do you see > >> any other potential outdated things in this document? I follow the above > >> steps and it help me compile the sample code successfully. > > > > Maybe we can reference that doc instead here? Otherwise that copy-pasted > > 11.0.0 will also get old. Just mention here that we need > > clang/llvm/pahole to compile the samples and for specific versions > > put a link to process/changes.rst > > > >>>> Clean and configuration > >>>> ----------------------- > >>>> > >>>> @@ -28,6 +31,10 @@ Configure kernel, defconfig for instance:: > >>>> > >>>> make defconfig > >>>> > >>>> +Some samples require support for BPF Type Format (BTF). To enable it, > >>>> open the > >>>> +generated config file, or use menuconfig (by "make menuconfig") to > >>>> enable the > >>>> +following configs: CONFIG_BPF_SYSCALL and CONFIG_DEBUG_INFO_BTF. > >>>> + > >>> > >>> This is usually enabled by default, so why special case it here? > >>> Maybe, if you want some hints about the config, we should add > >>> a reference to tools/testing/selftests/bpf/config ? > >>> > >> > >> The config CONFIG_DEBUG_INFO_BTF is disabled for some distros at least > >> for mine. I ran "make defconfig" and it's not enabled by default so I > >> think it worth to mention it here to help novice get started. I'll > >> update it to reference to tools/testing/selftests/bpf/config . > >> > >>>> Kernel headers > >>>> -------------- > >>>> > >>>> -- > >>>> 2.34.1 > > Signed-off-by: Anh Tuan Phan <tuananhlfc@xxxxxxxxx> > --- > > Change from the original patch: > > - Move pahole to the list installed requirements > - Remove minimal version and link the related doc > - Add a reference of kernel configuration > > samples/bpf/README.rst | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) > > diff --git a/samples/bpf/README.rst b/samples/bpf/README.rst > index 57f93edd1957..e18500753ba5 100644 > --- a/samples/bpf/README.rst > +++ b/samples/bpf/README.rst > @@ -8,9 +8,12 @@ Build dependencies > ================== > > Compiling requires having installed: > - * clang >= version 3.4.0 > - * llvm >= version 3.7.1 > + * clang > + * llvm > + * pahole > > +The minimal version of the above software is referenced in > +https://www.kernel.org/doc/html/next/process/changes.html. I think it is better to not use docs from linux-next as it keeps changing too frequently. How about using the latest documentation's link instead? :) https://www.kernel.org/doc/html/latest/process/changes.html However, something to think about is: If future versions of clang, llvm etc do not support compiling our code as it is now, it may become misleading. > Note that LLVM's tool 'llc' must support target 'bpf', list version > and supported targets with command: ``llc --version`` > > @@ -24,7 +27,8 @@ after some changes (on demand):: > make -C samples/bpf clean > make clean > > -Configure kernel, defconfig for instance:: > +Configure kernel, defconfig for instance > +(see "tools/testing/selftests/bpf/config" for a reference config):: > > make defconfig > > -- thanks, -- Khalid Masum
