[PATCH V2] tools/perf/tests: Update test_adding_kernel.sh to handle proper debuginfo check

[Athira Rajeev <atrajeev@linux.ibm.com>]

Perf test perftool-testsuite_probe fails as below:

 Regexp not found: "\s*probe:inode_permission(?:_\d+)?\s+\(on inode_permission(?:[:\+][0-9A-Fa-f]+)?@.+\)"
 -- [ FAIL ] -- perf_probe :: test_adding_kernel :: listing added probe :: perf probe -l (output regexp parsing)
 -- [ PASS ] -- perf_probe :: test_adding_kernel :: removing multiple probes
 Regexp not found: "probe:vfs_mknod"
 Regexp not found: "probe:vfs_create"
 Regexp not found: "probe:vfs_rmdir"
 Regexp not found: "probe:vfs_link"
 Regexp not found: "probe:vfs_write"
 -- [ FAIL ] -- perf_probe :: test_adding_kernel :: wildcard adding support (command exitcode + output regexp parsing)
 Regexp not found: "somenonexistingrandomstuffwhichisalsoprettylongorevenlongertoexceed64"
 Regexp not found: "in this function|at this address"
 -- [ FAIL ] -- perf_probe :: test_adding_kernel :: non-existing variable (output regexp parsing)
 ## [ FAIL ] ## perf_probe :: test_adding_kernel SUMMARY :: 3 failures found

Further analysing, the failed testcase is for "test_adding_kernel".
If the kernel debuginfo is missing, perf probe fails as below:

perf probe -nf --max-probes=512 -a 'vfs_* $params'
Failed to find the path for the kernel: No such file or directory
  Error: Failed to add events.

skip_if_no_debuginfo has check to handle whether debuginfo is present
and the testcase checks for debuginfo since this :
commit 90d32e92011e ("tools/perf: Handle perftool-testsuite_probe
testcases fail when kernel debuginfo is not present")

Recently a change got added in "tests/shell/lib/probe_vfs_getname.sh"
via this another fix:
commit 92b664dcefab ("perf test probe_vfs_getname: Skip if no suitable
line detected")
Since this commit, first add_probe_vfs_getname is used to prevent false
failures. And based on return code of add_probe_vfs_getname, skip_if_no_debuginfo
is used to skip testcase if debuginfo is present. And this modified other
testcases to call add_probe_vfs_getname first and invoke
skip_if_no_debuginfo based on return value.

The tests in test_adding_kernel.sh which depends on presence of
debuginfo are:
1. probe add for inode_permission
2. probe max-probes option using 'vfs_* $params'
3. non-existing variable probing

For these tests, probe check for specific line is not required.
So call skip_if_no_debuginfo with argument to say if line check is
needed. This is to convey to skip_if_no_debuginfo() function
that test only needs to check for debuginfo, and not specifically
line number. Update skip_if_no_debuginfo to use simple "perf probe"
check if test only needs to check for debuginfo. And for other
tests which rely on line number, use add_probe_vfs_getname()

With the change, verified that only three which required debuginfo only
is skipped and others ran successfully. Also tested with debuginfo
to make sure tests are not skipped.

Reported-by: Tejas Manhas <Tejas.Manhas1@ibm.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Athira Rajeev <atrajeev@linux.ibm.com>
---
Changelog:
- First version used "perf probe -v -L getname_flags" for debuginfo
  check. This will not catch fail string "Debuginfo-analysis is not
supported" which is used in cases when perf is built without dwarf.
 So use "perf probe -vn add inode_permission" to capture cases when
 tools built with NO_LIBDWARF=1. This will capture debuginfo missing as
well as tool built without dwarf case.

 .../tests/shell/base_probe/test_adding_kernel.sh  | 15 ++++++++++++++-
 tools/perf/tests/shell/lib/probe_vfs_getname.sh   | 13 ++++++++++++-
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/tools/perf/tests/shell/base_probe/test_adding_kernel.sh b/tools/perf/tests/shell/base_probe/test_adding_kernel.sh
index 555a825d55f2..f3db125c8669 100755
--- a/tools/perf/tests/shell/base_probe/test_adding_kernel.sh
+++ b/tools/perf/tests/shell/base_probe/test_adding_kernel.sh
@@ -23,10 +23,23 @@ TEST_RESULT=0
 . "$DIR_PATH/../lib/probe_vfs_getname.sh"
 
 TEST_PROBE=${TEST_PROBE:-"inode_permission"}
+PROBE_NO_LINE_CHECK=1
 
 # set NO_DEBUGINFO to skip testcase if debuginfo is not present
 # skip_if_no_debuginfo returns 2 if debuginfo is not present
-skip_if_no_debuginfo
+#
+# The perf probe checks which depends on presence of debuginfo and
+# used in this testcase are:
+# 1. probe add for inode_permission
+# 2. probe max-probes option using 'vfs_* $params'
+# 3. non-existing variable probing
+#
+# For these tests, probe check for specific line is not
+# required ( add_probe_vfs_getname does that ). So call
+# skip_if_no_debuginfo with argument as 1. This is to convey
+# that test only needs to check for debuginfo, and not specifically
+# line number
+skip_if_no_debuginfo $PROBE_NO_LINE_CHECK
 if [ $? -eq 2 ]; then
 	NO_DEBUGINFO=1
 fi
diff --git a/tools/perf/tests/shell/lib/probe_vfs_getname.sh b/tools/perf/tests/shell/lib/probe_vfs_getname.sh
index 88cd0e26d5f6..8ae2ea2bc8a2 100644
--- a/tools/perf/tests/shell/lib/probe_vfs_getname.sh
+++ b/tools/perf/tests/shell/lib/probe_vfs_getname.sh
@@ -39,7 +39,18 @@ add_probe_vfs_getname() {
 }
 
 skip_if_no_debuginfo() {
-	add_probe_vfs_getname -v 2>&1 | grep -E -q "^(Failed to find the path for the kernel|Debuginfo-analysis is not supported)|(file has no debug information)" && return 2
+	no_line_check=$1
+	debug_str="^(Failed to find the path for the kernel|Debuginfo-analysis is not supported)|(file has no debug information)"
+
+	# search for debug_str using simple perf probe if the
+	# test only needs to check for debuginfo, and not specifically
+	# line number.
+	if [ $no_line_check -eq 1 ]; then
+		perf probe -vn add inode_permission 2>&1 | grep -E -q "$debug_str" && return 2
+	else
+		add_probe_vfs_getname -v 2>&1 | grep -E -q "$debug_str" && return 2
+	fi
+
 	return 1
 }
 
-- 
2.47.3