netconsole: selftest: add task name append testing

Add test coverage for the netconsole task name feature to the existing
sysdata selftest script. This extends the test infrastructure to verify
that task names are correctly appended when enabled and absent when
disabled.

The test validates that:
  - Task names appear in the expected format "taskname=<name>"
  - Task names are included when the feature is enabled
  - Task names are excluded when the feature is disabled
  - The feature works correctly alongside other sysdata fields like CPU

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

tools/testing/selftests/drivers/net/netcons_sysdata.sh

@@ -31,17 +31,38 @@ function set_cpu_nr() {
 	echo 1 > "${NETCONS_PATH}/userdata/cpu_nr_enabled"
 }
 
+# Enable the taskname to be appended to sysdata
+function set_taskname() {
+	if [[ ! -f "${NETCONS_PATH}/userdata/taskname_enabled" ]]
+	then
+		echo "Not able to enable taskname sysdata append. Configfs not available in ${NETCONS_PATH}/userdata/taskname_enabled" >&2
+		exit "${ksft_skip}"
+	fi
+
+	echo 1 > "${NETCONS_PATH}/userdata/taskname_enabled"
+}
+
 # Disable the sysdata cpu_nr feature
 function unset_cpu_nr() {
 	echo 0 > "${NETCONS_PATH}/userdata/cpu_nr_enabled"
 }
 
-# Test if MSG content and `cpu=${CPU}` exists in OUTPUT_FILE
-function validate_sysdata_cpu_exists() {
+# Once called, taskname=<..> will not be appended anymore
+function unset_taskname() {
+	echo 0 > "${NETCONS_PATH}/userdata/taskname_enabled"
+}
+
+# Test if MSG contains sysdata
+function validate_sysdata() {
 	# OUTPUT_FILE will contain something like:
 	# 6.11.1-0_fbk0_rc13_509_g30d75cea12f7,13,1822,115075213798,-;netconsole selftest: netcons_gtJHM
 	#  userdatakey=userdatavalue
 	#  cpu=X
+	#  taskname=<taskname>
+
+	# Echo is what this test uses to create the message. See runtest()
+	# function
+	SENDER="echo"
 
 	if [ ! -f "$OUTPUT_FILE" ]; then
 		echo "FAIL: File was not generated." >&2
@@ -62,12 +83,19 @@ function validate_sysdata_cpu_exists() {
 		exit "${ksft_fail}"
 	fi
 
+	if ! grep -q "taskname=${SENDER}" "${OUTPUT_FILE}"; then
+		echo "FAIL: 'taskname=echo' not found in ${OUTPUT_FILE}" >&2
+		cat "${OUTPUT_FILE}" >&2
+		exit "${ksft_fail}"
+	fi
+
 	rm "${OUTPUT_FILE}"
 	pkill_socat
 }
 
-# Test if MSG content exists in OUTPUT_FILE but no `cpu=` string
-function validate_sysdata_no_cpu() {
+# Test if MSG content exists in OUTPUT_FILE but no `cpu=` and `taskname=`
+# strings
+function validate_no_sysdata() {
 	if [ ! -f "$OUTPUT_FILE" ]; then
 		echo "FAIL: File was not generated." >&2
 		exit "${ksft_fail}"
@@ -85,6 +113,12 @@ function validate_sysdata_no_cpu() {
 		exit "${ksft_fail}"
 	fi
 
+	if grep -q "taskname=" "${OUTPUT_FILE}"; then
+		echo "FAIL: 'taskname=  found in ${OUTPUT_FILE}" >&2
+		cat "${OUTPUT_FILE}" >&2
+		exit "${ksft_fail}"
+	fi
+
 	rm "${OUTPUT_FILE}"
 }
 
@@ -133,10 +167,12 @@ OUTPUT_FILE="/tmp/${TARGET}_1"
 MSG="Test #1 from CPU${CPU}"
 # Enable the auto population of cpu_nr
 set_cpu_nr
+# Enable taskname to be appended to sysdata
+set_taskname
 runtest
 # Make sure the message was received in the dst part
 # and exit
-validate_sysdata_cpu_exists
+validate_sysdata
 
 #====================================================
 # TEST #2
@@ -148,7 +184,7 @@ OUTPUT_FILE="/tmp/${TARGET}_2"
 MSG="Test #2 from CPU${CPU}"
 set_user_data
 runtest
-validate_sysdata_cpu_exists
+validate_sysdata
 
 # ===================================================
 # TEST #3
@@ -160,8 +196,9 @@ OUTPUT_FILE="/tmp/${TARGET}_3"
 MSG="Test #3 from CPU${CPU}"
 # Enable the auto population of cpu_nr
 unset_cpu_nr
+unset_taskname
 runtest
 # At this time, cpu= shouldn't be present in the msg
-validate_sysdata_no_cpu
+validate_no_sysdata
 
 exit "${ksft_pass}"