[v3] build: alias default build as generic

The current machine='default' build name is not descriptive. The actual
default build is machine='native'. Add an alternative string which does
the same build and better describes what we're building:
machine='generic'. Leave machine='default' for backwards compatibility.

Signed-off-by: Juraj Linkeš <juraj.linkes@pantheon.tech>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
---
 config/arm/meson.build                    |  7 ++++---
 config/meson.build                        | 13 +++++++------
 devtools/test-meson-builds.sh             | 14 +++++++-------
 doc/guides/prog_guide/build-sdk-meson.rst |  4 ++--
 meson_options.txt                         |  2 +-
 5 files changed, 21 insertions(+), 19 deletions(-)

Hi Thomas, David,

Is there anything missing in this patch? We have some acks and reviewed-by. Maybe add more documentation? If so, where?

Thanks,
Juuraj

> -----Original Message-----
> From: Juraj Linkeš <juraj.linkes@pantheon.tech>
> Sent: Thursday, February 18, 2021 3:13 PM
> To: bruce.richardson@intel.com; thomas@monjalon.net;
> Ruifeng.Wang@arm.com; Honnappa.Nagarahalli@arm.com;
> jerinjacobk@gmail.com; ferruh.yigit@intel.com
> Cc: dev@dpdk.org; Juraj Linkeš <juraj.linkes@pantheon.tech>
> Subject: [PATCH v3] build: alias default build as generic
> 
> The current machine='default' build name is not descriptive. The actual default
> build is machine='native'. Add an alternative string which does the same build
> and better describes what we're building:
> machine='generic'. Leave machine='default' for backwards compatibility.
> 
> Signed-off-by: Juraj Linkeš <juraj.linkes@pantheon.tech>
> Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
> Acked-by: Bruce Richardson <bruce.richardson@intel.com>
> ---
>  config/arm/meson.build                    |  7 ++++---
>  config/meson.build                        | 13 +++++++------
>  devtools/test-meson-builds.sh             | 14 +++++++-------
>  doc/guides/prog_guide/build-sdk-meson.rst |  4 ++--
>  meson_options.txt                         |  2 +-
>  5 files changed, 21 insertions(+), 19 deletions(-)
> 
> diff --git a/config/arm/meson.build b/config/arm/meson.build index
> 00bc4610a3..aaed89bd5b 100644
> --- a/config/arm/meson.build
> +++ b/config/arm/meson.build
> @@ -1,6 +1,7 @@
>  # SPDX-License-Identifier: BSD-3-Clause  # Copyright(c) 2017 Intel Corporation.
>  # Copyright(c) 2017 Cavium, Inc
> +# Copyright(c) 2021 PANTHEON.tech s.r.o.
> 
>  # common flags to all aarch64 builds, with lowest priority  flags_common = [
> @@ -208,8 +209,8 @@ if dpdk_conf.get('RTE_ARCH_32')  else
>  	# aarch64 build
>  	if not meson.is_cross_build()
> -		if machine == 'default'
> -			# default build
> +		if machine == 'generic'
> +			# generic build
>  			implementer_id = 'generic'
>  			part_number = 'generic'
>  		else
> @@ -256,7 +257,7 @@ else
>  		      '(-Dmachine=generic) build.')
>  	endif
> 
> -	# use default flags with implementer flags
> +	# use common flags with implementer flags
>  	dpdk_flags = flags_common + implementer_config['flags'] +
> part_number_config.get('flags', [])
> 
>  	# apply supported machine args
> diff --git a/config/meson.build b/config/meson.build index
> 3cf560b8a3..ed4de62b37 100644
> --- a/config/meson.build
> +++ b/config/meson.build
> @@ -70,21 +70,22 @@ else
>  	machine = get_option('machine')
>  endif
> 
> -# machine type 'default' is special, it defaults to the per arch agreed common -#
> minimal baseline needed for DPDK.
> +# machine type 'generic' is special, it selects the per arch agreed
> +common # minimal baseline needed for DPDK. Machine type 'default' is
> +also supported # with the same meaning for backwards compatibility.
>  # That might not be the most optimized, but the most portable version while  #
> still being able to support the CPU features required for DPDK.
>  # This can be bumped up by the DPDK project, but it can never be an  # invariant
> like 'native'
> -if machine == 'default'
> +if machine == 'default' or machine == 'generic'
>  	if host_machine.cpu_family().startswith('x86')
> -		# matches the old pre-meson build systems default
> +		# matches the old pre-meson build systems generic machine
>  		machine = 'corei7'
>  	elif host_machine.cpu_family().startswith('arm')
>  		machine = 'armv7-a'
>  	elif host_machine.cpu_family().startswith('aarch')
> -		# arm64 manages defaults in config/arm/meson.build
> -		machine = 'default'
> +		# arm64 manages generic config in config/arm/meson.build
> +		machine = 'generic'
>  	elif host_machine.cpu_family().startswith('ppc')
>  		machine = 'power8'
>  	endif
> diff --git a/devtools/test-meson-builds.sh b/devtools/test-meson-builds.sh index
> c11ae87e0d..daf817ac3e 100755
> --- a/devtools/test-meson-builds.sh
> +++ b/devtools/test-meson-builds.sh
> @@ -223,12 +223,12 @@ done
>  # test compilation with minimal x86 instruction set  # Set the install path for
> libraries to "lib" explicitly to prevent problems  # with pkg-config prefixes if
> installed in "lib/x86_64-linux-gnu" later.
> -default_machine='nehalem'
> -if ! check_cc_flags "-march=$default_machine" ; then
> -	default_machine='corei7'
> +generic_machine='nehalem'
> +if ! check_cc_flags "-march=$generic_machine" ; then
> +	generic_machine='corei7'
>  fi
> -build build-x86-default cc skipABI -Dcheck_includes=true \
> -	-Dlibdir=lib -Dmachine=$default_machine $use_shared
> +build build-x86-generic cc skipABI -Dcheck_includes=true \
> +	-Dlibdir=lib -Dmachine=$generic_machine $use_shared
> 
>  # 32-bit with default compiler
>  if check_cc_flags '-m32' ; then
> @@ -271,10 +271,10 @@ for f in $srcdir/config/ppc/ppc* ; do
>  	build $targetdir $f ABI $use_shared
>  done
> 
> -# Test installation of the x86-default target, to be used for checking
> +# Test installation of the x86-generic target, to be used for checking
>  # the sample apps build using the pkg-config file for cflags and libs  load_env cc
> -build_path=$(readlink -f $builds_dir/build-x86-default)
> +build_path=$(readlink -f $builds_dir/build-x86-generic)
>  export DESTDIR=$build_path/install
>  install_target $build_path $DESTDIR
>  pc_file=$(find $DESTDIR -name libdpdk.pc) diff --git
> a/doc/guides/prog_guide/build-sdk-meson.rst b/doc/guides/prog_guide/build-
> sdk-meson.rst
> index 3429e26479..c7e12eedfb 100644
> --- a/doc/guides/prog_guide/build-sdk-meson.rst
> +++ b/doc/guides/prog_guide/build-sdk-meson.rst
> @@ -85,7 +85,7 @@ Project-specific options are passed used -Doption=value::
> 
>  	meson -Denable_docs=true fullbuild  # build and install docs
> 
> -	meson -Dmachine=default  # use builder-independent baseline -march
> +	meson -Dmachine=generic  # use builder-independent baseline -march
> 
>  	meson -Ddisable_drivers=event/*,net/tap  # disable tap driver and all
>  					# eventdev PMDs for a smaller build
> @@ -114,7 +114,7 @@ Examples of setting some of the same options using
> meson configure::
>          re-scan from meson.
> 
>  .. note::
> -        machine=default uses a config that works on all supported architectures
> +        machine=generic uses a config that works on all supported
> + architectures
>          regardless of the capabilities of the machine where the build is happening.
> 
>  As well as those settings taken from ``meson configure``, other options diff --git
> a/meson_options.txt b/meson_options.txt index 6eff62e47d..2c7b46ef07
> 100644
> --- a/meson_options.txt
> +++ b/meson_options.txt
> @@ -21,7 +21,7 @@ option('include_subdir_arch', type: 'string', value: '',
> option('kernel_dir', type: 'string', value: '',
>  	description: 'Path to the kernel for building kernel modules. Headers
> must be in $kernel_dir/build. Modules will be installed in
> $DEST_DIR/$kernel_dir/extra/dpdk.')
>  option('machine', type: 'string', value: 'native',
> -	description: 'set the target machine type')
> +	description: 'set the target machine type or "generic", a build usable
> +on all machines of the build machine architecture or "native", which
> +lets the compiler pick the architecture of the build machine.')
>  option('max_ethports', type: 'integer', value: 32,
>  	description: 'maximum number of Ethernet devices')
> option('max_lcores', type: 'integer', value: 128,
> --
> 2.20.1