Re: [dpdk-dev] [PATCH] add ABI checks

["Kinsella, Ray" <ray.kinsella@intel.com>]

> -----Original Message-----
> From: Richardson, Bruce <bruce.richardson@intel.com>
> Sent: Friday 20 December 2019 15:32
> To: David Marchand <david.marchand@redhat.com>; dev@dpdk.org
> Cc: thomas@monjalon.net; Laatz, Kevin <kevin.laatz@intel.com>;
> aconole@redhat.com; nhorman@tuxdriver.com; Michael Santana
> <maicolgabriel@hotmail.com>; Mcnamara, John <john.mcnamara@intel.com>;
> Kovacevic, Marko <marko.kovacevic@intel.com>; Kinsella, Ray
> <ray.kinsella@intel.com>
> Subject: RE: [PATCH] add ABI checks
> 
> 
> 
> > -----Original Message-----
> > From: David Marchand <david.marchand@redhat.com>
> > Sent: Friday, December 20, 2019 3:21 PM
> > To: dev@dpdk.org
> > Cc: thomas@monjalon.net; Richardson, Bruce
> > <bruce.richardson@intel.com>; Laatz, Kevin <kevin.laatz@intel.com>;
> > aconole@redhat.com; nhorman@tuxdriver.com; Michael Santana
> > <maicolgabriel@hotmail.com>; Mcnamara, John
> <john.mcnamara@intel.com>;
> > Kovacevic, Marko <marko.kovacevic@intel.com>
> > Subject: [PATCH] add ABI checks
> >
> > Starting from Kevin and Bruce idea of using libabigail, here is an
> > alternate approach to implement ABI checks.
> >
> > By default, those checks are disabled and enabling them requires a
> > manual step that generates the ABI dumps on a reference version for a
> > set of configurations.
> >
> > Those checks are enabled in the CI by default for the default meson
> > options on x86 and aarch64 so that proposed patches are validated.
> > A cache of the ABI is stored in travis jobs.
> > Checks can be only informational by setting ABI_CHECKS_WARN_ONLY when
> > breaking the ABI in a future release.
> >
> > For advanced developers and maintainers, the contributing guide
> > details the higher level scripts that are quite close to the existing
> > devtools scripts.
> >
> > Signed-off-by: David Marchand <david.marchand@redhat.com>
> > ---
> >  .ci/linux-build.sh                  | 43 +++++++++++++++++++++++++++
> >  .travis.yml                         | 20 +++++++++++--
> >  devtools/check-abi-dump.sh          | 46
> +++++++++++++++++++++++++++++
> >  devtools/check-abi-reference.sh     | 27 +++++++++++++++++
> >  devtools/dpdk.abignore              |  2 ++
> >  devtools/gen-abi-dump.sh            | 29 ++++++++++++++++++
> >  devtools/gen-abi-reference.sh       | 24 +++++++++++++++
> >  devtools/test-build.sh              | 13 ++++++--
> >  devtools/test-meson-builds.sh       |  6 ++++
> >  doc/guides/contributing/patches.rst | 25 ++++++++++++++++
> >  10 files changed, 230 insertions(+), 5 deletions(-)  create mode
> > 100755 devtools/check-abi-dump.sh  create mode 100755
> > devtools/check-abi- reference.sh  create mode 100644
> > devtools/dpdk.abignore  create mode
> > 100755 devtools/gen-abi-dump.sh  create mode 100755 devtools/gen-abi-
> > reference.sh
> >
> > diff --git a/.ci/linux-build.sh b/.ci/linux-build.sh index
> > ccc3a7ccd..345dba264 100755
> > --- a/.ci/linux-build.sh
> > +++ b/.ci/linux-build.sh
> > @@ -30,8 +30,51 @@ fi
> >
> >  OPTS="$OPTS --default-library=$DEF_LIB"
> >  meson build --werror -Dexamples=all $OPTS
> > +
> > +if [ "$ABI_CHECKS" = "1" ]; then
> > +    git remote add ref ${REF_GIT_REPO:-https://dpdk.org/git/dpdk}
> > +    git fetch --tags ref ${REF_GIT_BRANCH:-master}
> > +
> > +    head=$(git describe --all)
> > +    tag=$(git describe --abbrev=0)
> > +
> > +    if [ "$(cat reference/VERSION 2>/dev/null)" != "$tag" ]; then
> > +        rm -rf reference
> > +    fi
> > +
> > +    if [ ! -d reference ]; then
> > +        gen_abi_dump=$(mktemp -t gen-abi-dump-XXX.sh)
> > +        cp -a devtools/gen-abi-dump.sh $gen_abi_dump
> > +
> > +        git checkout -qf $tag
> > +        ninja -C build
> > +        $gen_abi_dump build reference
> > +
> > +        if [ "$AARCH64" != "1" ]; then
> > +            mkdir -p reference/app
> > +            cp -a build/app/dpdk-testpmd reference/app/
> > +
> > +            export
> LD_LIBRARY_PATH=$(pwd)/build/lib:$(pwd)/build/drivers
> > +            devtools/test-null.sh reference/app/dpdk-testpmd
> > +            unset LD_LIBRARY_PATH
> > +        fi
> > +        echo $tag > reference/VERSION
> > +
> > +        git checkout -qf $head
> > +    fi
> > +fi
> > +
> >  ninja -C build
> >
> > +if [ "$ABI_CHECKS" = "1" ]; then
> > +    devtools/check-abi-dump.sh build reference
> ${ABI_CHECKS_WARN_ONLY:-}
> > +    if [ "$AARCH64" != "1" ]; then
> > +        export LD_LIBRARY_PATH=$(pwd)/build/lib:$(pwd)/build/drivers
> > +        devtools/test-null.sh reference/app/dpdk-testpmd
> > +        unset LD_LIBRARY_PATH
> > +    fi
> > +fi
> > +
> >  if [ "$AARCH64" != "1" ]; then
> >      devtools/test-null.sh
> >  fi
> > diff --git a/.travis.yml b/.travis.yml index 8f90d06f2..bbb060fa2
> > 100644
> > --- a/.travis.yml
> > +++ b/.travis.yml
> > @@ -1,5 +1,8 @@
> >  language: c
> > -cache: ccache
> > +cache:
> > +  ccache: true
> > +  directories:
> > +    - reference
> >  compiler:
> >    - gcc
> >    - clang
> > @@ -21,7 +24,7 @@ aarch64_packages: &aarch64_packages
> >
> >  extra_packages: &extra_packages
> >    - *required_packages
> > -  - [libbsd-dev, libpcap-dev, libcrypto++-dev, libjansson4]
> > +  - [libbsd-dev, libpcap-dev, libcrypto++-dev, libjansson4,
> > + abigail-tools]
> >
> >  build_32b_packages: &build_32b_packages
> >    - *required_packages
> > @@ -59,6 +62,13 @@ matrix:
> >        apt:
> >          packages:
> >            - *aarch64_packages
> > +  - env: DEF_LIB="shared" EXTRA_PACKAGES=1 ABI_CHECKS=1 AARCH64=1
> > +    compiler: gcc
> > +    addons:
> > +      apt:
> > +        packages:
> > +          - *aarch64_packages
> > +          - *extra_packages
> >    - env: DEF_LIB="static" EXTRA_PACKAGES=1
> >      compiler: gcc
> >      addons:
> > @@ -72,6 +82,12 @@ matrix:
> >          packages:
> >            - *extra_packages
> >            - *doc_packages
> > +  - env: DEF_LIB="shared" EXTRA_PACKAGES=1 ABI_CHECKS=1
> > +    compiler: gcc
> > +    addons:
> > +      apt:
> > +        packages:
> > +          - *extra_packages
> >    - env: DEF_LIB="static" OPTS="-Denable_kmods=false"
> EXTRA_PACKAGES=1
> >      compiler: gcc
> >      addons:
> > diff --git a/devtools/check-abi-dump.sh b/devtools/check-abi-dump.sh
> > new file mode 100755 index 000000000..f48a2ae7e
> > --- /dev/null
> > +++ b/devtools/check-abi-dump.sh
> > @@ -0,0 +1,46 @@
> > +#!/bin/sh -e
> > +# SPDX-License-Identifier: BSD-3-Clause # Copyright (c) 2019 Red
> Hat,
> > +Inc.
> > +
> > +if [ $# != 2 ] && [ $# != 3 ]; then
> > +	echo "Usage: $0 builddir dumpdir [warnonly]"
> > +	exit 1
> > +fi
> > +
> > +builddir=$1
> > +dumpdir=$2
> > +warnonly=${3:-}
> > +if [ ! -d $builddir ]; then
> > +	echo "Error: build directory '$builddir' does not exist."
> > +	exit 1
> > +fi
> > +if [ ! -d $dumpdir ]; then
> > +	echo "Error: dump directory '$dumpdir' does not exist."
> > +	exit 1
> > +fi
> > +
> > +ABIDIFF_OPTIONS="--suppr $(dirname $0)/dpdk.abignore"
> > +for dump in $(find $dumpdir -name "*.dump"); do
> > +	libname=$(basename $dump)
> > +	libname=${libname%.dump}
> > +	result=
> > +	for f in $(find $builddir -name "$libname.so.*"); do
> > +		if test -L $f || [ "$f" != "${f%%.symbols}" ]; then
> > +			continue
> > +		fi
> > +		result=found
> > +
> > +		if ! abidiff $ABIDIFF_OPTIONS $dump $f; then
> > +			if [ -z "$warnonly" ]; then
> > +				echo "Error: ABI issue reported for $dump, $f"
> > +				exit 1
> > +			fi
> > +			echo "Warning: ABI issue reported for $dump, $f"
> > +		fi
> > +		break
> > +	done
> > +	if [ "$result" != "found" ]; then
> > +		echo "Error: can't find a library for dump file $dump"
> > +		exit 1
> > +	fi
> > +done
> > diff --git a/devtools/check-abi-reference.sh b/devtools/check-abi-
> > reference.sh new file mode 100755 index 000000000..7addb094e
> > --- /dev/null
> > +++ b/devtools/check-abi-reference.sh
> > @@ -0,0 +1,27 @@
> > +#!/bin/sh -e
> > +# SPDX-License-Identifier: BSD-3-Clause # Copyright (c) 2019 Red
> Hat,
> > +Inc.
> > +
> > +devtools_dir=$(dirname $(readlink -f $0)) .
> > +$devtools_dir/load-devel-config
> > +
> > +abi_ref_build_dir=${DPDK_ABI_REF_BUILD_DIR:-reference}
> > +builds_dir=${DPDK_BUILD_TEST_DIR:-.}
> > +
> > +for dir in $abi_ref_build_dir/*; do
> > +	if [ "$dir" = "$abi_ref_build_dir" ]; then
> > +		exit 1
> > +	fi
> > +	if [ ! -d $dir/dump ]; then
> > +		echo "Skipping $dir"
> > +		continue
> > +	fi
> > +	target=$(basename $dir)
> > +	if [ -d $builds_dir/$target/install ]; then
> > +		libdir=$builds_dir/$target/install
> > +	else
> > +		libdir=$builds_dir/$target
> > +	fi
> > +	echo "Checking ABI between $libdir and $dir/dump"
> > +	$devtools_dir/check-abi-dump.sh $libdir $dir/dump done
> > diff --git a/devtools/dpdk.abignore b/devtools/dpdk.abignore new file
> > mode
> > 100644 index 000000000..b866b7f26
> > --- /dev/null
> > +++ b/devtools/dpdk.abignore
> > @@ -0,0 +1,2 @@
> > +[suppress_function]
> > +        symbol_version = EXPERIMENTAL
> > diff --git a/devtools/gen-abi-dump.sh b/devtools/gen-abi-dump.sh new
> > file mode 100755 index 000000000..4e38d751f
> > --- /dev/null
> > +++ b/devtools/gen-abi-dump.sh
> > @@ -0,0 +1,29 @@
> > +#!/bin/sh -e
> > +# SPDX-License-Identifier: BSD-3-Clause # Copyright (c) 2019 Red
> Hat,
> > +Inc.
> > +
> > +if [ $# != 2 ]; then
> > +	echo "Usage: $0 builddir dumpdir"
> > +	exit 1
> > +fi
> > +
> > +builddir=$1
> > +dumpdir=$2
> > +if [ ! -d $builddir ]; then
> > +	echo "Error: build directory '$builddir' does not exist."
> > +	exit 1
> > +fi
> > +if [ -d $dumpdir ]; then
> > +	echo "Error: dump directory '$dumpdir' already exists."
> > +	exit 1
> > +fi
> > +
> > +mkdir -p $dumpdir
> > +for f in $(find $builddir -name "*.so.*"); do
> > +	if test -L $f || [ "$f" != "${f%%.symbols}" ]; then
> > +		continue
> > +	fi
> > +
> > +	libname=$(basename $f)
> > +	abidw --out-file $dumpdir/${libname%.so.*}.dump $f done
> > diff --git a/devtools/gen-abi-reference.sh
> > b/devtools/gen-abi-reference.sh new file mode 100755 index
> > 000000000..f41d7fadc
> > --- /dev/null
> > +++ b/devtools/gen-abi-reference.sh
> > @@ -0,0 +1,24 @@
> > +#!/bin/sh -e
> > +# SPDX-License-Identifier: BSD-3-Clause # Copyright (c) 2019 Red
> Hat,
> > +Inc.
> > +
> > +devtools_dir=$(dirname $(readlink -f $0)) .
> > +$devtools_dir/load-devel-config
> > +
> > +abi_ref_build_dir=${DPDK_ABI_REF_BUILD_DIR:-reference}
> > +for dir in $abi_ref_build_dir/*; do
> > +	if [ "$dir" = "$abi_ref_build_dir" ]; then
> > +		exit 1
> > +	fi
> > +	if [ -d $dir/dump ]; then
> > +		echo "Skipping $dir"
> > +		continue
> > +	fi
> > +	if [ -d $dir/install ]; then
> > +		libdir=$dir/install
> > +	else
> > +		libdir=$dir
> > +	fi
> > +	echo "Dumping libraries from $libdir in $dir/dump"
> > +	$devtools_dir/gen-abi-dump.sh $libdir $dir/dump done
> > diff --git a/devtools/test-build.sh b/devtools/test-build.sh index
> > 52305fbb8..8cb5b56fb 100755
> > --- a/devtools/test-build.sh
> > +++ b/devtools/test-build.sh
> > @@ -30,7 +30,8 @@ default_path=$PATH
> >  # - LIBSSO_SNOW3G_PATH
> >  # - LIBSSO_KASUMI_PATH
> >  # - LIBSSO_ZUC_PATH
> > -. $(dirname $(readlink -f $0))/load-devel-config
> > +devtools_dir=$(dirname $(readlink -f $0)) .
> > +$devtools_dir/load-devel-config
> >
> >  print_usage () {
> >  	echo "usage: $(basename $0) [-h] [-jX] [-s] [config1 [config2]
> > ...]]"
> > @@ -64,6 +65,7 @@ print_help () {
> >  [ -z $MAKE ] && echo "Cannot find make or gmake" && exit 1
> >
> >  J=$DPDK_MAKE_JOBS
> > +abi_ref_build_dir=${DPDK_ABI_REF_BUILD_DIR:-reference}
> >  builds_dir=${DPDK_BUILD_TEST_DIR:-.}
> >  short=false
> >  unset verbose
> > @@ -97,7 +99,7 @@ trap "signal=INT ; trap - INT ; kill -INT $$" INT
> #
> > notify result on exit  trap on_exit EXIT
> >
> > -cd $(dirname $(readlink -f $0))/..
> > +cd $devtools_dir/..
> >
> >  reset_env ()
> >  {
> > @@ -233,7 +235,7 @@ for conf in $configs ; do
> >  	# reload config with DPDK_TARGET set
> >  	DPDK_TARGET=$target
> >  	reset_env
> > -	. $(dirname $(readlink -f $0))/load-devel-config
> > +	. $devtools_dir/load-devel-config
> >
> >  	options=$(echo $conf | sed 's,[^~+]*,,')
> >  	dir=$builds_dir/$conf
> > @@ -246,6 +248,11 @@ for conf in $configs ; do
> >  	export RTE_TARGET=$target
> >  	rm -rf $dir/install
> >  	${MAKE} install O=$dir DESTDIR=$dir/install prefix=
> > +	if [ -d $abi_ref_build_dir/$conf/dump ]; then
> > +		echo "================== Check ABI $conf"
> > +		$devtools_dir/check-abi-dump.sh $dir/install \
> > +			$abi_ref_build_dir/$conf/dump
> > +	fi
> >  	echo "================== Build examples for $conf"
> >  	export RTE_SDK=$(readlink -f $dir)/install/share/dpdk
> >  	ln -sTf $(pwd)/lib $RTE_SDK/lib # workaround for vm_power_manager
> > diff --git a/devtools/test-meson-builds.sh
> > b/devtools/test-meson-builds.sh index 688567714..aaefa38a2 100755
> > --- a/devtools/test-meson-builds.sh
> > +++ b/devtools/test-meson-builds.sh
> > @@ -16,6 +16,7 @@ srcdir=$(dirname $(readlink -f $0))/..
> >
> >  MESON=${MESON:-meson}
> >  use_shared="--default-library=shared"
> > +abi_ref_build_dir=${DPDK_ABI_REF_BUILD_DIR:-reference}
> >  builds_dir=${DPDK_BUILD_TEST_DIR:-.}
> >
> >  if command -v gmake >/dev/null 2>&1 ; then @@ -88,6 +89,11 @@ build
> > () # <directory> <target compiler> <meson options>
> >  		echo "$ninja_cmd -C $builddir"
> >  		$ninja_cmd -C $builddir
> >  	fi
> > +
> > +	if [ -d $abi_ref_build_dir/$1/dump ]; then
> > +		$srcdir/devtools/check-abi-dump.sh $builddir
> > +			$abi_ref_build_dir/$1/dump
> > +	fi
> >  }
> >
> >  if [ "$1" = "-vv" ] ; then
> > diff --git a/doc/guides/contributing/patches.rst
> > b/doc/guides/contributing/patches.rst
> > index 0686450e4..de3dff145 100644
> > --- a/doc/guides/contributing/patches.rst
> > +++ b/doc/guides/contributing/patches.rst
> > @@ -513,6 +513,31 @@ in a single subfolder called "__builds" created
> > in the current directory.
> >  Setting ``DPDK_BUILD_TEST_DIR`` to an absolute directory path e.g.
> > ``/tmp`` is also supported.
> >
> >
> > +Checking ABI compatibility
> > +--------------------------
> > +
> > +The first thing is to build reference binaries for the latest
> release
> > +your patches are built on top of.
> > +
> > +Either you are in a git tree and an easy way to identify this is to
> run::
> > +
> > +  git checkout $(git describe --abbrev=0)
> > +
> > +Or you use a tarball and you extract the sources in a director of
> > +your
> > choice.
> > +
> > +Next is building those sources, refer to the previous paragraph.
> > +You can set ``DPDK_BUILD_TEST_DIR=reference``, so that the builds
> > +occur in this directory.
> > +
> > +Finally, the ABI dump files are generated with the
> > +``devtools/gen-abi-reference.sh`` script. This script will look for
> > +builds in the current sub directory ``reference``. But you can set
> > +the environment variable ``DPDK_ABI_REF_BUILD_DIR`` to a different
> location.
> > +
> > +Once done, you can check your current binaries ABI with this
> > +reference with the ``devtools/check-abi-reference.sh`` script.
> > +
> > +
> >  Sending Patches
> >  ---------------
> >
> > --
> > 2.23.0
> 
> I still very much dislike forcing the user to generate his own
> reference version to compare the ABI against. These should be archived
> and the user should just be able to pull them down via git or http or
> otherwise. Two reasons for this:
> 
> 1. Less error prone, since there is no chance of the user having an
> incorrect build for whatever reason.
> 
> 2. Less effort for the user than asking them to do extra builds. The
> more steps the user has to follow, the less likely they are to attempt
> the process.
> 
> Regards,
> /Bruce
> 

+1 ... 100% agree with this.

Many people won't know or understand what the reference is, 
or why they to generate it. 

Ray K