On Fri, Feb 05, 2021 at 03:46:37PM +0100, Juraj Linkeš wrote:
> The kni linux module is using a custom target for building, which
> doesn't take into account any cross compilation arguments. The arguments
> in question are ARCH, CROSS_COMPILE (for gcc, clang) and CC, LD (for
> clang). Get those from the cross file and pass them to the custom
> target.
>
> The user supplied path may not contain the 'build' directory, such as
> when using cross-compiled headers, so only append that in the default
> case (when no path is supplied in native builds) and use the unmodified
> path from the user otherwise. Also modify the install path accordingly.
>
> Signed-off-by: Juraj Linkeš <juraj.lin...@pantheon.tech>
> ---
> kernel/linux/kni/meson.build | 8 ++--
> kernel/linux/meson.build | 79 ++++++++++++++++++++++++++++++------
> 2 files changed, 70 insertions(+), 17 deletions(-)
>
> diff --git a/kernel/linux/kni/meson.build b/kernel/linux/kni/meson.build
> index 07e0c9dae7..46b71c7418 100644
> --- a/kernel/linux/kni/meson.build
> +++ b/kernel/linux/kni/meson.build
> @@ -13,7 +13,7 @@ kni_sources = files(
> custom_target('rte_kni',
> input: kni_sources,
> output: 'rte_kni.ko',
> - command: ['make', '-j4', '-C', kernel_dir + '/build',
> + command: ['make', '-j4', '-C', kernel_build_dir,
> 'M=' + meson.current_build_dir(),
> 'src=' + meson.current_source_dir(),
> 'MODULE_CFLAGS=-include ' + meson.source_root() +
> '/config/rte_config.h' +
> @@ -21,8 +21,8 @@ custom_target('rte_kni',
> ' -I' + meson.source_root() + '/lib/librte_kni' +
> ' -I' + meson.build_root() +
> ' -I' + meson.current_source_dir(),
> - 'modules'],
> + 'modules'] + cross_args,
> depends: kni_mkfile,
> - install: true,
> - install_dir: kernel_dir + '/extra/dpdk',
> + install: install,
> + install_dir: kernel_install_dir,
> build_by_default: get_option('enable_kmods'))
> diff --git a/kernel/linux/meson.build b/kernel/linux/meson.build
> index 5c864a4653..4271483329 100644
> --- a/kernel/linux/meson.build
> +++ b/kernel/linux/meson.build
> @@ -3,24 +3,77 @@
>
> subdirs = ['kni']
>
> -# if we are cross-compiling we need kernel_dir specified
> -if get_option('kernel_dir') == '' and meson.is_cross_build()
> - error('Need "kernel_dir" option for kmod compilation when
> cross-compiling')
> -endif
> +kernel_build_dir = get_option('kernel_dir')
> +install = not meson.is_cross_build()
> +cross_args = []
> +kernel_install_dir = ''
>
> -kernel_dir = get_option('kernel_dir')
> -if kernel_dir == ''
> - # use default path for native builds
> +if install
I'd suggest using explicit "not meson.is_cross_build" again for
readability.
> + # native build
> kernel_version = run_command('uname', '-r').stdout().strip()
> - kernel_dir = '/lib/modules/' + kernel_version
> + kernel_install_dir = '/lib/modules/' + kernel_version + '/extra/dpdk'
> + if kernel_build_dir == ''
> + # use default path for native builds
> + kernel_build_dir = '/lib/modules/' + kernel_version + '/build'
> + endif
> +
> + # test running make in kernel directory, using "make kernelversion"
> + make_returncode = run_command('make', '-sC', kernel_build_dir,
> + 'kernelversion').returncode()
> + if make_returncode != 0
> + error('Cannot compile kernel modules as requested - are kernel
> headers installed?')
> + endif
> +
> + # DO ACTUAL MODULE BUILDING
> + foreach d:subdirs
> + subdir(d)
> + endforeach
> +
> + subdir_done()
> endif
>
> -# test running make in kernel directory, using "make kernelversion"
> -make_returncode = run_command('make', '-sC', kernel_dir + '/build',
> - 'kernelversion').returncode()
> -if make_returncode != 0
> - error('Cannot compile kernel modules as requested - are kernel headers
> installed?')
> +# cross build
> +# if we are cross-compiling we need kernel_build_dir specified
> +if kernel_build_dir == ''
> + error('Need "kernel_dir" option for kmod compilation when
> cross-compiling')
> +endif
> +cross_compiler = find_program('c').path()
> +if cross_compiler.endswith('gcc')
> + cross_prefix = run_command([py3, '-c', 'print("' + cross_compiler +
> '"[:-3])']).stdout().strip()
> +elif cross_compiler.endswith('clang')
> + cross_prefix = ''
> + found_target = false
> + # search for '-target' and use the arg that follows
> + # (i.e. the value of '-target') as cross_prefix
> + foreach cross_c_arg : meson.get_cross_property('c_args')
> + if found_target and cross_prefix == ''
> + cross_prefix = cross_c_arg
> + endif
> + if cross_c_arg == '-target'
> + found_target = true
> + endif
> + endforeach
> + if cross_prefix == ''
> + error('Didn\'t find -target and its value in' +
> + ' c_args in input cross-file.')
> + endif
> + linker = 'lld'
> + foreach cross_c_link_arg : meson.get_cross_property('c_link_args')
> + if cross_c_link_arg.startswith('-fuse-ld')
> + linker = cross_c_link_arg.split('=')[1]
> + endif
> + endforeach
> + cross_args += ['CC=@0@'.format(cross_compiler),
> 'LD=ld.@0@'.format(linker)]
> +else
> + error('Unsupported cross compiler: @0@'.format(cross_compiler))
> +endif
> +if host_machine.cpu_family() == 'aarch64'
> + cross_arch = 'arm64'
> +else
> + cross_arch = build_machine.cpu_family()
> endif
Is this not meant to be "host_machine.cpu_family()"?
I also think this might be simpler as:
cross_arch = host_machine.cpu_family()
if cross_arch == 'aarch64'
cross_arch = arm64
endif
> +cross_args += ['ARCH=@0@'.format(cross_arch),
> + 'CROSS_COMPILE=@0@'.format(cross_prefix)]
>
> # DO ACTUAL MODULE BUILDING
> foreach d:subdirs
> --
> 2.20.1
>
