[v3] devtools: parallelize ABI check

  Generation and comparison of ABI dumps are done on multiple cores
thanks to xargs -P0.
It can accelerate this long step by 5 in my tests.

xargs reports a global error if one of the process has an error.

Running a shell function with xargs requires to export it with -f,
and that is a specific capability of bash.

Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
Tested-by: Ferruh Yigit <ferruh.yigit@amd.com>
---
v2:
	- find dump2 inside the function
	- force bash because of export -f
v3:
	- revert to POSIX sh
	- use POSIX eval instead of export -f (issues on Ubuntu)
---
 devtools/check-abi.sh | 21 +++++++++++++--------
 devtools/gen-abi.sh   |  5 +++--
 2 files changed, 16 insertions(+), 10 deletions(-)
  

On Wed, Jan 11, 2023 at 02:16:52PM +0100, Thomas Monjalon wrote:
> Generation and comparison of ABI dumps are done on multiple cores
> thanks to xargs -P0.
> It can accelerate this long step by 5 in my tests.
> 
> xargs reports a global error if one of the process has an error.
> 
> Running a shell function with xargs requires to export it with -f,
> and that is a specific capability of bash.
> 
Commit-log needs update based on changes in v3.

> Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
> Tested-by: Ferruh Yigit <ferruh.yigit@amd.com>
> ---
> v2:
> 	- find dump2 inside the function
> 	- force bash because of export -f
> v3:
> 	- revert to POSIX sh
> 	- use POSIX eval instead of export -f (issues on Ubuntu)
> ---
>  devtools/check-abi.sh | 21 +++++++++++++--------
>  devtools/gen-abi.sh   |  5 +++--
>  2 files changed, 16 insertions(+), 10 deletions(-)
  

On Wed, Jan 11, 2023 at 2:16 PM Thomas Monjalon <thomas@monjalon.net> wrote:
>
> Generation and comparison of ABI dumps are done on multiple cores
> thanks to xargs -P0.
> It can accelerate this long step by 5 in my tests.
>
> xargs reports a global error if one of the process has an error.
>
> Running a shell function with xargs requires to export it with -f,
> and that is a specific capability of bash.
>
> Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
> Tested-by: Ferruh Yigit <ferruh.yigit@amd.com>
> ---
> v2:
>         - find dump2 inside the function
>         - force bash because of export -f
> v3:
>         - revert to POSIX sh
>         - use POSIX eval instead of export -f (issues on Ubuntu)
> ---
>  devtools/check-abi.sh | 21 +++++++++++++--------
>  devtools/gen-abi.sh   |  5 +++--
>  2 files changed, 16 insertions(+), 10 deletions(-)
>
> diff --git a/devtools/check-abi.sh b/devtools/check-abi.sh
> index c583eae2fd..d58c867c60 100755
> --- a/devtools/check-abi.sh
> +++ b/devtools/check-abi.sh
> @@ -34,19 +34,18 @@ else
>         ABIDIFF_OPTIONS="$ABIDIFF_OPTIONS --headers-dir2 $incdir2"
>  fi
>
> -error=
> -for dump in $(find $refdir -name "*.dump"); do
> +export diff_func='run_diff() {
> +       dump=$1
> +       newdir=$2
>         name=$(basename $dump)
>         dump2=$(find $newdir -name $name)
>         if [ -z "$dump2" ] || [ ! -e "$dump2" ]; then
>                 echo "Error: cannot find $name in $newdir" >&2
> -               error=1
> -               continue
> -       fi
> +               return 1
> +       fi;
>         abidiff $ABIDIFF_OPTIONS $dump $dump2 || {
>                 abiret=$?
> -               echo "Error: ABI issue reported for 'abidiff $ABIDIFF_OPTIONS $dump $dump2'" >&2
> -               error=1
> +               echo "Error: ABI issue reported for abidiff $ABIDIFF_OPTIONS $dump $dump2" >&2
>                 echo
>                 if [ $(($abiret & 3)) -ne 0 ]; then
>                         echo "ABIDIFF_ERROR|ABIDIFF_USAGE_ERROR, this could be a script or environment issue." >&2
> @@ -58,7 +57,13 @@ for dump in $(find $refdir -name "*.dump"); do
>                         echo "ABIDIFF_ABI_INCOMPATIBLE_CHANGE, this change breaks the ABI." >&2
>                 fi
>                 echo
> +               return 1
>         }
> -done
> +}'
> +
> +error=
> +find $refdir -name "*.dump" |
> +xargs -n1 -P0 sh -c 'eval "$diff_func"; run_diff $0 '$newdir ||
> +error=1

Do we need to pass $newdir ?
Like, for example, ABIDIFF_OPTIONS seems inherited, right?

Otherwise this trick looks to work.
  

11/01/2023 15:11, David Marchand:
> On Wed, Jan 11, 2023 at 2:16 PM Thomas Monjalon <thomas@monjalon.net> wrote:
> > +find $refdir -name "*.dump" |
> > +xargs -n1 -P0 sh -c 'eval "$diff_func"; run_diff $0 '$newdir ||
> > +error=1
> 
> Do we need to pass $newdir ?
> Like, for example, ABIDIFF_OPTIONS seems inherited, right?

Actually ABIDIFF_OPTIONS was empty when calling the function.
I'll pass it as well.