| Message ID | 20160426110927.20716.89620.stgit@firesoul (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 04/26/2016 01:09 PM, Jesper Dangaard Brouer wrote: > Getting started with using examples in samples/bpf/ is not > straightforward. There are several dependencies, and specific > versions of these dependencies. > > Just compiling the example tool is also slightly obscure, e.g. one > need to call make like: > > make samples/bpf/ > > Do notice the "/" slash after the directory name. > > Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> > --- > samples/bpf/README.rst | 67 ++++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 67 insertions(+) > create mode 100644 samples/bpf/README.rst > > diff --git a/samples/bpf/README.rst b/samples/bpf/README.rst > new file mode 100644 > index 000000000000..3e1ac05d8e7c > --- /dev/null > +++ b/samples/bpf/README.rst > @@ -0,0 +1,67 @@ > +eBPF sample programs > +==================== > + > +This kernel samples/bpf directory contains a mini eBPF library, test > +stubs, verifier test-suite and examples for using eBPF. > + > +Build dependencies > +================== > + > +Compiling requires having installed: > + * clang > + * llvm >= version 3.7.0 > + > +Note that LLVM's tool 'llc' must support target 'bpf', list with command:: > + > + $ llc --version > + LLVM (http://llvm.org/): > + LLVM version 3.x.y > + [...] > + Host CPU: xxx > + > + Registered Targets: > + [...] > + bpf - BPF (host endian) > + bpfeb - BPF (big endian) > + bpfel - BPF (little endian) > + [...] > + > +Kernel headers > +-------------- > + > +There are usually dependencies to header files of the current kernel. > +To avoid installing devel kernel headers system wide, as a normal > +user, simply call:: > + > + make headers_install > + > +This will creates a local "usr/include" directory in the git/build top > +level directory, that the make system automatically pickup first. > + > +Compiling > +========= > + > +For compiling goto kernel top level build directory and run make like:: > + > + make samples/bpf/ > + > +Do notice the "/" slash after the directory name. > + > +Manually compiling LLVM with 'bpf' support > +------------------------------------------ > + > +In some LLVM versions the BPF target were marked experimental. To > +compile LLVM manually and enable BPF target run (build dependencies > +are cmake and gcc-c++):: > + > + $ git clone http://llvm.org/git/llvm.git > + $ cd llvm > + $ mkdir build; cd build > + $ cmake .. -DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD=BPF > + $ make That's perhaps a bit misleading in the sense that when you clone the tree from git, you'd nowadays invoke cmake normally with LLVM_TARGETS_TO_BUILD instead of LLVM_EXPERIMENTAL_TARGETS_TO_BUILD for BPF, as BPF is not an experimental target anymore. It's probably also recommended to clone clang into tools/ dir as well under your llvm/ repo when you compile from scratch anyways. > +It is also possible to point make to the newly compile 'llc' command > +via redefining LLC on the make command line:: > + > + make samples/bpf/ LLC=~/git/llvm/build/bin/llc > + > -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, 26 Apr 2016 13:44:06 +0200 Daniel Borkmann <daniel@iogearbox.net> wrote: > On 04/26/2016 01:09 PM, Jesper Dangaard Brouer wrote: > > Getting started with using examples in samples/bpf/ is not > > straightforward. There are several dependencies, and specific > > versions of these dependencies. > > > > Just compiling the example tool is also slightly obscure, e.g. one > > need to call make like: > > > > make samples/bpf/ > > > > Do notice the "/" slash after the directory name. > > > > Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> > > --- > > samples/bpf/README.rst | 67 ++++++++++++++++++++++++++++++++++++++++++++++++ > > 1 file changed, 67 insertions(+) > > create mode 100644 samples/bpf/README.rst > > > > diff --git a/samples/bpf/README.rst b/samples/bpf/README.rst > > new file mode 100644 > > index 000000000000..3e1ac05d8e7c > > --- /dev/null > > +++ b/samples/bpf/README.rst > > @@ -0,0 +1,67 @@ > > +eBPF sample programs > > +==================== > > + > > +This kernel samples/bpf directory contains a mini eBPF library, test > > +stubs, verifier test-suite and examples for using eBPF. > > + > > +Build dependencies > > +================== > > + > > +Compiling requires having installed: > > + * clang > > + * llvm >= version 3.7.0 > > + > > +Note that LLVM's tool 'llc' must support target 'bpf', list with command:: > > + > > + $ llc --version > > + LLVM (http://llvm.org/): > > + LLVM version 3.x.y > > + [...] > > + Host CPU: xxx > > + > > + Registered Targets: > > + [...] > > + bpf - BPF (host endian) > > + bpfeb - BPF (big endian) > > + bpfel - BPF (little endian) > > + [...] > > + > > +Kernel headers > > +-------------- > > + > > +There are usually dependencies to header files of the current kernel. > > +To avoid installing devel kernel headers system wide, as a normal > > +user, simply call:: > > + > > + make headers_install > > + > > +This will creates a local "usr/include" directory in the git/build top > > +level directory, that the make system automatically pickup first. > > + > > +Compiling > > +========= > > + > > +For compiling goto kernel top level build directory and run make like:: > > + > > + make samples/bpf/ > > + > > +Do notice the "/" slash after the directory name. > > + > > +Manually compiling LLVM with 'bpf' support > > +------------------------------------------ > > + > > +In some LLVM versions the BPF target were marked experimental. To > > +compile LLVM manually and enable BPF target run (build dependencies > > +are cmake and gcc-c++):: > > + > > + $ git clone http://llvm.org/git/llvm.git > > + $ cd llvm > > + $ mkdir build; cd build > > + $ cmake .. -DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD=BPF > > + $ make > > That's perhaps a bit misleading in the sense that when you clone the > tree from git, you'd nowadays invoke cmake normally with LLVM_TARGETS_TO_BUILD > instead of LLVM_EXPERIMENTAL_TARGETS_TO_BUILD for BPF, as BPF is not an > experimental target anymore. It's probably also recommended to clone > clang into tools/ dir as well under your llvm/ repo when you compile > from scratch anyways. Can you come up with a formulation/desc I can use instead then?
On 04/26/2016 01:56 PM, Jesper Dangaard Brouer wrote: > On Tue, 26 Apr 2016 13:44:06 +0200 > Daniel Borkmann <daniel@iogearbox.net> wrote: > >> On 04/26/2016 01:09 PM, Jesper Dangaard Brouer wrote: >>> Getting started with using examples in samples/bpf/ is not >>> straightforward. There are several dependencies, and specific >>> versions of these dependencies. >>> >>> Just compiling the example tool is also slightly obscure, e.g. one >>> need to call make like: >>> >>> make samples/bpf/ >>> >>> Do notice the "/" slash after the directory name. >>> >>> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> >>> --- >>> samples/bpf/README.rst | 67 ++++++++++++++++++++++++++++++++++++++++++++++++ >>> 1 file changed, 67 insertions(+) >>> create mode 100644 samples/bpf/README.rst >>> >>> diff --git a/samples/bpf/README.rst b/samples/bpf/README.rst >>> new file mode 100644 >>> index 000000000000..3e1ac05d8e7c >>> --- /dev/null >>> +++ b/samples/bpf/README.rst >>> @@ -0,0 +1,67 @@ >>> +eBPF sample programs >>> +==================== >>> + >>> +This kernel samples/bpf directory contains a mini eBPF library, test >>> +stubs, verifier test-suite and examples for using eBPF. >>> + >>> +Build dependencies >>> +================== >>> + >>> +Compiling requires having installed: >>> + * clang >>> + * llvm >= version 3.7.0 >>> + >>> +Note that LLVM's tool 'llc' must support target 'bpf', list with command:: >>> + >>> + $ llc --version >>> + LLVM (http://llvm.org/): >>> + LLVM version 3.x.y >>> + [...] >>> + Host CPU: xxx >>> + >>> + Registered Targets: >>> + [...] >>> + bpf - BPF (host endian) >>> + bpfeb - BPF (big endian) >>> + bpfel - BPF (little endian) >>> + [...] >>> + >>> +Kernel headers >>> +-------------- >>> + >>> +There are usually dependencies to header files of the current kernel. >>> +To avoid installing devel kernel headers system wide, as a normal >>> +user, simply call:: >>> + >>> + make headers_install >>> + >>> +This will creates a local "usr/include" directory in the git/build top >>> +level directory, that the make system automatically pickup first. >>> + >>> +Compiling >>> +========= >>> + >>> +For compiling goto kernel top level build directory and run make like:: >>> + >>> + make samples/bpf/ >>> + >>> +Do notice the "/" slash after the directory name. >>> + >>> +Manually compiling LLVM with 'bpf' support >>> +------------------------------------------ >>> + >>> +In some LLVM versions the BPF target were marked experimental. To >>> +compile LLVM manually and enable BPF target run (build dependencies >>> +are cmake and gcc-c++):: >>> + >>> + $ git clone http://llvm.org/git/llvm.git >>> + $ cd llvm >>> + $ mkdir build; cd build >>> + $ cmake .. -DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD=BPF >>> + $ make >> >> That's perhaps a bit misleading in the sense that when you clone the >> tree from git, you'd nowadays invoke cmake normally with LLVM_TARGETS_TO_BUILD >> instead of LLVM_EXPERIMENTAL_TARGETS_TO_BUILD for BPF, as BPF is not an >> experimental target anymore. It's probably also recommended to clone >> clang into tools/ dir as well under your llvm/ repo when you compile >> from scratch anyways. > > Can you come up with a formulation/desc I can use instead then? You mean how to build with clang? There are various docs/snippets out there, for example, see the 'Build LLVM and Clang development libs' part of [1], that you can tweak for your README with. [1] https://gist.github.com/brendangregg/cfa482acb71aa577789c -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, Apr 26, 2016 at 02:40:54PM +0200, Daniel Borkmann wrote: > On 04/26/2016 01:56 PM, Jesper Dangaard Brouer wrote: > >>>+Compiling requires having installed: > >>>+ * clang > >>>+ * llvm >= version 3.7.0 please change it to 3.7.1, since 3.7.0 had several bugs. They're rare, but better to avoid the issue. > >>>+ > >>>+Note that LLVM's tool 'llc' must support target 'bpf', list with command:: > >>>+ > >>>+ $ llc --version > >>>+ LLVM (http://llvm.org/): > >>>+ LLVM version 3.x.y > >>>+ [...] > >>>+ Host CPU: xxx > >>>+ > >>>+ Registered Targets: > >>>+ [...] > >>>+ bpf - BPF (host endian) > >>>+ bpfeb - BPF (big endian) > >>>+ bpfel - BPF (little endian) there always be 3 targets for bpf, since some folks need to cross-compile. > >>>+Manually compiling LLVM with 'bpf' support > >>>+------------------------------------------ > >>>+ > >>>+In some LLVM versions the BPF target were marked experimental. To > >>>+compile LLVM manually and enable BPF target run (build dependencies > >>>+are cmake and gcc-c++):: > >>>+ > >>>+ $ git clone http://llvm.org/git/llvm.git > >>>+ $ cd llvm > >>>+ $ mkdir build; cd build > >>>+ $ cmake .. -DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD=BPF > >>>+ $ make > >> > >>That's perhaps a bit misleading in the sense that when you clone the > >>tree from git, you'd nowadays invoke cmake normally with LLVM_TARGETS_TO_BUILD > >>instead of LLVM_EXPERIMENTAL_TARGETS_TO_BUILD for BPF, as BPF is not an > >>experimental target anymore. It's probably also recommended to clone > >>clang into tools/ dir as well under your llvm/ repo when you compile > >>from scratch anyways. yes. LLVM_EXPERIMENTAL_TARGETS_TO_BUILD is the thing of the past when bpf was just merged into llvm < 3.7 By default llvm will build all non-experimental backends including bpf. If you need to make llc binary smaller you can use: -DLLVM_TARGETS_TO_BUILD="BPF;X86" Also fedora and ubuntu ship with llvm that has bpf support. > >Can you come up with a formulation/desc I can use instead then? > > You mean how to build with clang? There are various docs/snippets out > there, for example, see the 'Build LLVM and Clang development libs' > part of [1], that you can tweak for your README with. > > [1] https://gist.github.com/brendangregg/cfa482acb71aa577789c yep. +1 for the link. -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/samples/bpf/README.rst b/samples/bpf/README.rst new file mode 100644 index 000000000000..3e1ac05d8e7c --- /dev/null +++ b/samples/bpf/README.rst @@ -0,0 +1,67 @@ +eBPF sample programs +==================== + +This kernel samples/bpf directory contains a mini eBPF library, test +stubs, verifier test-suite and examples for using eBPF. + +Build dependencies +================== + +Compiling requires having installed: + * clang + * llvm >= version 3.7.0 + +Note that LLVM's tool 'llc' must support target 'bpf', list with command:: + + $ llc --version + LLVM (http://llvm.org/): + LLVM version 3.x.y + [...] + Host CPU: xxx + + Registered Targets: + [...] + bpf - BPF (host endian) + bpfeb - BPF (big endian) + bpfel - BPF (little endian) + [...] + +Kernel headers +-------------- + +There are usually dependencies to header files of the current kernel. +To avoid installing devel kernel headers system wide, as a normal +user, simply call:: + + make headers_install + +This will creates a local "usr/include" directory in the git/build top +level directory, that the make system automatically pickup first. + +Compiling +========= + +For compiling goto kernel top level build directory and run make like:: + + make samples/bpf/ + +Do notice the "/" slash after the directory name. + +Manually compiling LLVM with 'bpf' support +------------------------------------------ + +In some LLVM versions the BPF target were marked experimental. To +compile LLVM manually and enable BPF target run (build dependencies +are cmake and gcc-c++):: + + $ git clone http://llvm.org/git/llvm.git + $ cd llvm + $ mkdir build; cd build + $ cmake .. -DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD=BPF + $ make + +It is also possible to point make to the newly compile 'llc' command +via redefining LLC on the make command line:: + + make samples/bpf/ LLC=~/git/llvm/build/bin/llc +
Getting started with using examples in samples/bpf/ is not straightforward. There are several dependencies, and specific versions of these dependencies. Just compiling the example tool is also slightly obscure, e.g. one need to call make like: make samples/bpf/ Do notice the "/" slash after the directory name. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> --- samples/bpf/README.rst | 67 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) create mode 100644 samples/bpf/README.rst -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html