Re: [PATCH v2] perf test probe_vfs_getname: Skip if no suitable line detected

[Namhyung Kim]

Hello,

On Thu, Mar 13, 2025 at 05:58:24PM +0100, Jakub Brnak wrote:
> In some cases when calling function add_probe_vfs_getname, line number
> can't be detected by perf probe -L getname_flags:
> 
>   78         atomic_set(&result->refcnt, 1);
> 
> 	     // one of the following lines should have line number
> 	     // but sometimes it does not because of optimization
> 	     result->uptr = filename;
>              result->aname = NULL;
> 
>   81         audit_getname(result);
> 
> To prevent false failures, skip the affected tests
> if no suitable line numbers can be detected.
> 
> 
> Signed-off-by: Jakub Brnak <jbrnak@xxxxxxxxxx>
> ---
> v2:
> - check if return from add_vfs_getname equals to 1 since
> it is only option in case of fail
> 
> v1: https://lore.kernel.org/linux-perf-users/Z8pAep0GJsMFTyEi@xxxxxxxxxx/T/#t
> ---
>  tools/perf/tests/shell/lib/probe_vfs_getname.sh          | 8 +++++++-
>  tools/perf/tests/shell/probe_vfs_getname.sh              | 8 +++++++-
>  .../perf/tests/shell/record+script_probe_vfs_getname.sh  | 8 +++++++-
>  tools/perf/tests/shell/trace+probe_vfs_getname.sh        | 9 +++++++--
>  4 files changed, 28 insertions(+), 5 deletions(-)
> 
> diff --git a/tools/perf/tests/shell/lib/probe_vfs_getname.sh b/tools/perf/tests/shell/lib/probe_vfs_getname.sh
> index 5c33ec7a5a63..89f72a4c818c 100644
> --- a/tools/perf/tests/shell/lib/probe_vfs_getname.sh
> +++ b/tools/perf/tests/shell/lib/probe_vfs_getname.sh
> @@ -19,8 +19,14 @@ add_probe_vfs_getname() {
>  			result_aname_re="[[:space:]]+([[:digit:]]+)[[:space:]]+result->aname = NULL;"
>  			line=$(perf probe -L getname_flags 2>&1 | grep -E "$result_aname_re" | sed -r "s/$result_aname_re/\1/")
>  		fi
> +
> +		if [ -z "$line" ] ; then
> +			echo "Could not find probeable line"
> +			return 2
> +		fi
> +
>  		perf probe -q       "vfs_getname=getname_flags:${line} pathname=result->name:string" || \
> -		perf probe $add_probe_verbose "vfs_getname=getname_flags:${line} pathname=filename:ustring"
> +		perf probe $add_probe_verbose "vfs_getname=getname_flags:${line} pathname=filename:ustring" || return 1
>  	fi
>  }
>  
> diff --git a/tools/perf/tests/shell/probe_vfs_getname.sh b/tools/perf/tests/shell/probe_vfs_getname.sh
> index c51a32931af6..b210576f1971 100755
> --- a/tools/perf/tests/shell/probe_vfs_getname.sh
> +++ b/tools/perf/tests/shell/probe_vfs_getname.sh
> @@ -13,7 +13,13 @@ skip_if_no_perf_probe || exit 2
>  # shellcheck source=lib/probe_vfs_getname.sh
>  . "$(dirname $0)"/lib/probe_vfs_getname.sh
>  
> -add_probe_vfs_getname || skip_if_no_debuginfo
> +add_probe_vfs_getname
>  err=$?
> +
> +if [[ $err -eq 1 ]] ; then

I got this error from shellcheck.

  In tests/shell/probe_vfs_getname.sh line 19:
  if [[ $err -eq 1 ]] ; then
     ^--------------^ SC3010 (warning): In POSIX sh, [[ ]] is undefined.
  
  For more information:
    https://www.shellcheck.net/wiki/SC3010 -- In POSIX sh, [[ ]] is undefined.

Thanks,
Namhyung


> +	skip_if_no_debuginfo
> +	err=$?
> +fi
> +
>  cleanup_probe_vfs_getname
>  exit $err
> diff --git a/tools/perf/tests/shell/record+script_probe_vfs_getname.sh b/tools/perf/tests/shell/record+script_probe_vfs_getname.sh
> index fd5b10d46915..a26248d52628 100755
> --- a/tools/perf/tests/shell/record+script_probe_vfs_getname.sh
> +++ b/tools/perf/tests/shell/record+script_probe_vfs_getname.sh
> @@ -35,8 +35,14 @@ perf_script_filenames() {
>  	grep -E " +touch +[0-9]+ +\[[0-9]+\] +[0-9]+\.[0-9]+: +probe:vfs_getname[_0-9]*: +\([[:xdigit:]]+\) +pathname=\"${file}\""
>  }
>  
> -add_probe_vfs_getname || skip_if_no_debuginfo
> +add_probe_vfs_getname
>  err=$?
> +
> +if [[ $err -eq 1 ]] ; then
> +        skip_if_no_debuginfo
> +        err=$?
> +fi
> +
>  if [ $err -ne 0 ] ; then
>  	exit $err
>  fi
> diff --git a/tools/perf/tests/shell/trace+probe_vfs_getname.sh b/tools/perf/tests/shell/trace+probe_vfs_getname.sh
> index 60fccb62c540..4956cd9be41f 100755
> --- a/tools/perf/tests/shell/trace+probe_vfs_getname.sh
> +++ b/tools/perf/tests/shell/trace+probe_vfs_getname.sh
> @@ -25,9 +25,14 @@ trace_open_vfs_getname() {
>  	grep -E " +[0-9]+\.[0-9]+ +\( +[0-9]+\.[0-9]+ ms\): +touch/[0-9]+ open(at)?\((dfd: +CWD, +)?filename: +\"?${file}\"?, +flags: CREAT\|NOCTTY\|NONBLOCK\|WRONLY, +mode: +IRUGO\|IWUGO\) += +[0-9]+$"
>  }
>  
> -
> -add_probe_vfs_getname || skip_if_no_debuginfo
> +add_probe_vfs_getname
>  err=$?
> +
> +if [[ $err -eq 1 ]] ; then
> +        skip_if_no_debuginfo
> +        err=$?
> +fi
> +
>  if [ $err -ne 0 ] ; then
>  	exit $err
>  fi
> -- 
> 2.48.1
>