[PATCH v2] perf test probe_vfs_getname: Add regex for searching probe line

[PATCH v2] perf test probe_vfs_getname: Add regex for searching probe line

[Leo Yan]

Since commit 611851010c74 ("fs: dedup handling of struct filename init
and refcounts bumps"), the kernel has been refactored to use a new
inline function initname(), moving name initialization into it.

As a result, the perf probe test can no longer find the source line that
matches the defined regular expressions. This causes the script to fail
when attempting to add probes.

Add a regular expression to search for the call site of initname(). This
provides a valid source line number for adding the probe. Keeps the
older regular expressions for passing test on older kernels.

Suggested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Fixes: 611851010c74 ("fs: dedup handling of struct filename init and refcounts bumps")
Signed-off-by: Leo Yan <leo.yan@arm.com>
---

Changes from v1:
- Keep old regexps to be compatible with older kernels (Arnaldo)

 tools/perf/tests/shell/lib/probe_vfs_getname.sh | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/tools/perf/tests/shell/lib/probe_vfs_getname.sh b/tools/perf/tests/shell/lib/probe_vfs_getname.sh
index 89f72a4c818c..58debce9ab42 100644
--- a/tools/perf/tests/shell/lib/probe_vfs_getname.sh
+++ b/tools/perf/tests/shell/lib/probe_vfs_getname.sh
@@ -13,8 +13,16 @@ cleanup_probe_vfs_getname() {
 add_probe_vfs_getname() {
 	add_probe_verbose=$1
 	if [ $had_vfs_getname -eq 1 ] ; then
-		result_filename_re="[[:space:]]+([[:digit:]]+)[[:space:]]+result->uptr.*"
-		line=$(perf probe -L getname_flags 2>&1 | grep -E "$result_filename_re" | sed -r "s/$result_filename_re/\1/")
+		result_initname_re="[[:space:]]+([[:digit:]]+)[[:space:]]+initname.*"
+		line=$(perf probe -L getname_flags 2>&1 | grep -E "$result_initname_re" | sed -r "s/$result_initname_re/\1/")
+
+		# Search the old regular expressions so that this will
+		# pass on older kernels as well.
+		if [ -z "$line" ] ; then
+			result_filename_re="[[:space:]]+([[:digit:]]+)[[:space:]]+result->uptr.*"
+			line=$(perf probe -L getname_flags 2>&1 | grep -E "$result_filename_re" | sed -r "s/$result_filename_re/\1/")
+		fi
+
 		if [ -z "$line" ] ; then
 			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/")
-- 
2.34.1

Re: [PATCH v2] perf test probe_vfs_getname: Add regex for searching probe line

[Arnaldo Carvalho de Melo]

On Mon, May 19, 2025 at 09:27:55AM +0100, Leo Yan wrote:
> Since commit 611851010c74 ("fs: dedup handling of struct filename init
> and refcounts bumps"), the kernel has been refactored to use a new
> inline function initname(), moving name initialization into it.
> 
> As a result, the perf probe test can no longer find the source line that
> matches the defined regular expressions. This causes the script to fail
> when attempting to add probes.
> 
> Add a regular expression to search for the call site of initname(). This
> provides a valid source line number for adding the probe. Keeps the
> older regular expressions for passing test on older kernels.

Thanks, tested and applied.

- Arnaldo

> 
> Suggested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
> Fixes: 611851010c74 ("fs: dedup handling of struct filename init and refcounts bumps")
> Signed-off-by: Leo Yan <leo.yan@arm.com>
> ---
> 
> Changes from v1:
> - Keep old regexps to be compatible with older kernels (Arnaldo)
> 
>  tools/perf/tests/shell/lib/probe_vfs_getname.sh | 12 ++++++++++--
>  1 file changed, 10 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/perf/tests/shell/lib/probe_vfs_getname.sh b/tools/perf/tests/shell/lib/probe_vfs_getname.sh
> index 89f72a4c818c..58debce9ab42 100644
> --- a/tools/perf/tests/shell/lib/probe_vfs_getname.sh
> +++ b/tools/perf/tests/shell/lib/probe_vfs_getname.sh
> @@ -13,8 +13,16 @@ cleanup_probe_vfs_getname() {
>  add_probe_vfs_getname() {
>  	add_probe_verbose=$1
>  	if [ $had_vfs_getname -eq 1 ] ; then
> -		result_filename_re="[[:space:]]+([[:digit:]]+)[[:space:]]+result->uptr.*"
> -		line=$(perf probe -L getname_flags 2>&1 | grep -E "$result_filename_re" | sed -r "s/$result_filename_re/\1/")
> +		result_initname_re="[[:space:]]+([[:digit:]]+)[[:space:]]+initname.*"
> +		line=$(perf probe -L getname_flags 2>&1 | grep -E "$result_initname_re" | sed -r "s/$result_initname_re/\1/")
> +
> +		# Search the old regular expressions so that this will
> +		# pass on older kernels as well.
> +		if [ -z "$line" ] ; then
> +			result_filename_re="[[:space:]]+([[:digit:]]+)[[:space:]]+result->uptr.*"
> +			line=$(perf probe -L getname_flags 2>&1 | grep -E "$result_filename_re" | sed -r "s/$result_filename_re/\1/")
> +		fi
> +
>  		if [ -z "$line" ] ; then
>  			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/")
> -- 
> 2.34.1
>