Tom Stellard via llvm-dev
2021-Jan-11 17:14 UTC
[llvm-dev] BPF: How can I enable BPF support in my LLVM toolchain?
On 1/11/21 9:11 AM, Sedat Dilek wrote:> On Mon, Jan 11, 2021 at 4:35 PM Tom Stellard <tstellar at redhat.com> wrote: >> >> On 1/11/21 5:35 AM, Sedat Dilek via llvm-dev wrote: >>> Hi, >>> >>> when building a Linux-kernel with CONFIG_DEBUG_INFO_BTF=y my build breaks. >>> >> >> I commented on the GitHub issue about the root cause of this. >> >>> This is because my selfmade LLVM toolchain v11.0.1 has no BPF support: >>> >>> $ llc --version >>> LLVM (http://llvm.org/): >>> LLVM version 11.0.1 >>> Optimized build. >>> Default target: x86_64-unknown-linux-gnu >>> Host CPU: sandybridge >>> >>> Registered Targets: >>> x86 - 32-bit X86: Pentium-Pro and above >>> x86-64 - 64-bit X86: EM64T and AMD64 >>> >>> What system or binary requirements do I need and which CMAKE option(s) >>> need(s) to be set? >> >> The LLVM_TARGETS_TO_BUILD CMake option controls which targets to build. >> > > tc-build folks fixed that up. > See commit "build-llvm.py: Enable BPF backend by default". > > Is there a BPF test-suite - like for clang and lld? >There's one in the kernel. -Tom> I have build pahole from Git - now building a new Linux kernel. > > $ cd /path/to/pahole/git > $ git describe > v1.19-7-gb688e3597060 > > Will report later. > > Regards, > - Sedat - > > [1] https://github.com/ClangBuiltLinux/tc-build/commit/e796c046428a971404eec008c841f9dd7c1621e8 > >> -Tom >> >>> I hope this is not hardware-dependent (here: Intel SandyBridge). >>> >>> Thanks in advance. >>> >>> Regards, >>> - Sedat - >>> >>> [1] https://github.com/ClangBuiltLinux/tc-build/issues/129 >>> _______________________________________________ >>> LLVM Developers mailing list >>> llvm-dev at lists.llvm.org >>> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev >>> >> >
Sedat Dilek via llvm-dev
2021-Jan-11 17:27 UTC
[llvm-dev] BPF: How can I enable BPF support in my LLVM toolchain?
On Mon, Jan 11, 2021 at 6:14 PM Tom Stellard <tstellar at redhat.com> wrote:> > On 1/11/21 9:11 AM, Sedat Dilek wrote: > > On Mon, Jan 11, 2021 at 4:35 PM Tom Stellard <tstellar at redhat.com> wrote: > >> > >> On 1/11/21 5:35 AM, Sedat Dilek via llvm-dev wrote: > >>> Hi, > >>> > >>> when building a Linux-kernel with CONFIG_DEBUG_INFO_BTF=y my build breaks. > >>> > >> > >> I commented on the GitHub issue about the root cause of this. > >> > >>> This is because my selfmade LLVM toolchain v11.0.1 has no BPF support: > >>> > >>> $ llc --version > >>> LLVM (http://llvm.org/): > >>> LLVM version 11.0.1 > >>> Optimized build. > >>> Default target: x86_64-unknown-linux-gnu > >>> Host CPU: sandybridge > >>> > >>> Registered Targets: > >>> x86 - 32-bit X86: Pentium-Pro and above > >>> x86-64 - 64-bit X86: EM64T and AMD64 > >>> > >>> What system or binary requirements do I need and which CMAKE option(s) > >>> need(s) to be set? > >> > >> The LLVM_TARGETS_TO_BUILD CMake option controls which targets to build. > >> > > > > tc-build folks fixed that up. > > See commit "build-llvm.py: Enable BPF backend by default". > > > > Is there a BPF test-suite - like for clang and lld? > > > > There's one in the kernel. >Can I run it before compiling a single-line of a Linux-kernel? Does it test for BTF stuff? How do I run it? - Sedat -> -Tom > > > I have build pahole from Git - now building a new Linux kernel. > > > > $ cd /path/to/pahole/git > > $ git describe > > v1.19-7-gb688e3597060 > > > > Will report later. > > > > Regards, > > - Sedat - > > > > [1] https://github.com/ClangBuiltLinux/tc-build/commit/e796c046428a971404eec008c841f9dd7c1621e8 > > > >> -Tom > >> > >>> I hope this is not hardware-dependent (here: Intel SandyBridge). > >>> > >>> Thanks in advance. > >>> > >>> Regards, > >>> - Sedat - > >>> > >>> [1] https://github.com/ClangBuiltLinux/tc-build/issues/129 > >>> _______________________________________________ > >>> LLVM Developers mailing list > >>> llvm-dev at lists.llvm.org > >>> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev > >>> > >> > > >