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

From: Jakub Brnak
Date: Thu Mar 13 2025 - 12:58:57 EST


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 [[ $err -eq 1 ]] ; then
+ skip_if_no_debuginfo
+ err=$?
+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