Merge branch 'selftest-rds'

Allison Henderson says:

====================
selftests: rds selftest

This series is a new selftest that Vegard, Chuck and myself have been
working on to provide some test coverage for rds.  I've modified the
scripts to include the feedback from the last version, but let me know
if there's anything missed.  Questions and comments appreciated.

Thanks everyone!

Allison

Changes in v2:
- Removed qemu vm creation and related code
- Updated README.txt with examples of running the test with virtme
- Removed init.sh. run.sh now directly calls test.py
- Some clean up done with the return code handling since there is no
  vm between the scripts anymore
- Imported ip python function in
tools/testing/selftests/net/lib/py/utils.py into test.py
- Adapted test.py to use the imported ip function, and removed the
local ip wrapper
- Some line wrap clean up
- Link to v1:
https://lore.kernel.org/netdev/20240626012834.5678-3-allison.henderson@oracle.com/T
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

.gitignore

@@ -24,6 +24,7 @@
 *.dwo
 *.elf
 *.gcno
+*.gcda
 *.gz
 *.i
 *.ko

Documentation/dev-tools/gcov.rst

@@ -75,6 +75,17 @@ Only files which are linked to the main kernel image or are compiled as
 kernel modules are supported by this mechanism.
 
 
+Module specific configs
+-----------------------
+
+Gcov kernel configs for specific modules are described below:
+
+CONFIG_GCOV_PROFILE_RDS:
+        Enables GCOV profiling on RDS for checking which functions or
+        lines are executed. This config is used by the rds selftest to
+        generate coverage reports. If left unset the report is omitted.
+
+
 Files
 -----
 

MAINTAINERS

@@ -19197,6 +19197,7 @@ S:	Supported
 W:	https://oss.oracle.com/projects/rds/
 F:	Documentation/networking/rds.rst
 F:	net/rds/
+F:	tools/testing/selftests/net/rds/
 
 RDT - RESOURCE ALLOCATION
 M:	Fenghua Yu <fenghua.yu@intel.com>

net/rds/Kconfig

@@ -26,3 +26,12 @@ config RDS_DEBUG
 	bool "RDS debugging messages"
 	depends on RDS
 	default n
+
+config GCOV_PROFILE_RDS
+	bool "Enable GCOV profiling on RDS"
+	depends on GCOV_KERNEL
+	help
+	  Enable GCOV profiling on RDS for checking which functions/lines
+	  are executed.
+
+	  If unsure, say N.

net/rds/Makefile

@@ -15,3 +15,8 @@ rds_tcp-y :=		tcp.o tcp_connect.o tcp_listen.o tcp_recv.o \
 			tcp_send.o tcp_stats.o
 
 ccflags-$(CONFIG_RDS_DEBUG)	:=	-DRDS_DEBUG
+
+# for GCOV coverage profiling
+ifdef CONFIG_GCOV_PROFILE_RDS
+GCOV_PROFILE := y
+endif

tools/testing/selftests/Makefile

@@ -68,6 +68,7 @@ TARGETS += net/mptcp
 TARGETS += net/openvswitch
 TARGETS += net/tcp_ao
 TARGETS += net/netfilter
+TARGETS += net/rds
 TARGETS += nsfs
 TARGETS += perf_events
 TARGETS += pidfd

tools/testing/selftests/net/rds/Makefile

@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: GPL-2.0
+
+all:
+	@echo mk_build_dir="$(shell pwd)" > include.sh
+
+TEST_PROGS := run.sh \
+	include.sh \
+	test.py
+
+EXTRA_CLEAN := /tmp/rds_logs
+
+include ../../lib.mk

tools/testing/selftests/net/rds/README.txt

@@ -0,0 +1,41 @@
+RDS self-tests
+==============
+
+These scripts provide a coverage test for RDS-TCP by creating two
+network namespaces and running rds packets between them. A loopback
+network is provisioned with optional probability of packet loss or
+corruption. A workload of 50000 hashes, each 64 characters in size,
+are passed over an RDS socket on this test network. A passing test means
+the RDS-TCP stack was able to recover properly.  The provided config.sh
+can be used to compile the kernel with the necessary gcov options.  The
+kernel may optionally be configured to omit the coverage report as well.
+
+USAGE:
+	run.sh [-d logdir] [-l packet_loss] [-c packet_corruption]
+	       [-u packet_duplcate]
+
+OPTIONS:
+	-d	Log directory.  Defaults to tools/testing/selftests/net/rds/rds_logs
+
+	-l	Simulates a percentage of packet loss
+
+	-c	Simulates a percentage of packet corruption
+
+	-u	Simulates a percentage of packet duplication.
+
+EXAMPLE:
+
+    # Create a suitable gcov enabled .config
+    tools/testing/selftests/net/rds/config.sh -g
+
+    # Alternatly create a gcov disabled .config
+    tools/testing/selftests/net/rds/config.sh
+
+    # build the kernel
+    vng --build  --config tools/testing/selftests/net/config
+
+    # launch the tests in a VM
+    vng -v --rwdir ./ --run . --user root --cpus 4 -- \
+        "export PYTHONPATH=tools/testing/selftests/net/; tools/testing/selftests/net/rds/run.sh"
+
+An HTML coverage report will be output in tools/testing/selftests/net/rds/rds_logs/coverage/.

tools/testing/selftests/net/rds/config.sh

@@ -0,0 +1,53 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+set -e
+set -u
+set -x
+
+unset KBUILD_OUTPUT
+
+GENERATE_GCOV_REPORT=0
+while getopts "g" opt; do
+  case ${opt} in
+    g)
+      GENERATE_GCOV_REPORT=1
+      ;;
+    :)
+      echo "USAGE: config.sh [-g]"
+      exit 1
+      ;;
+    ?)
+      echo "Invalid option: -${OPTARG}."
+      exit 1
+      ;;
+  esac
+done
+
+CONF_FILE="tools/testing/selftests/net/config"
+
+# no modules
+scripts/config --file "$CONF_FILE" --disable CONFIG_MODULES
+
+# enable RDS
+scripts/config --file "$CONF_FILE" --enable CONFIG_RDS
+scripts/config --file "$CONF_FILE" --enable CONFIG_RDS_TCP
+
+if [ "$GENERATE_GCOV_REPORT" -eq 1 ]; then
+	# instrument RDS and only RDS
+	scripts/config --file "$CONF_FILE" --enable CONFIG_GCOV_KERNEL
+	scripts/config --file "$CONF_FILE" --disable GCOV_PROFILE_ALL
+	scripts/config --file "$CONF_FILE" --enable GCOV_PROFILE_RDS
+else
+	scripts/config --file "$CONF_FILE" --disable CONFIG_GCOV_KERNEL
+	scripts/config --file "$CONF_FILE" --disable GCOV_PROFILE_ALL
+	scripts/config --file "$CONF_FILE" --disable GCOV_PROFILE_RDS
+fi
+
+# need network namespaces to run tests with veth network interfaces
+scripts/config --file "$CONF_FILE" --enable CONFIG_NET_NS
+scripts/config --file "$CONF_FILE" --enable CONFIG_VETH
+
+# simulate packet loss
+scripts/config --file "$CONF_FILE" --enable CONFIG_NET_SCH_NETEM
+

tools/testing/selftests/net/rds/run.sh

@@ -0,0 +1,224 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+set -e
+set -u
+
+unset KBUILD_OUTPUT
+
+current_dir="$(realpath "$(dirname "$0")")"
+build_dir="$current_dir"
+
+build_include="$current_dir/include.sh"
+if test -f "$build_include"; then
+	# this include will define "$mk_build_dir" as the location the test was
+	# built.  We will need this if the tests are installed in a location
+	# other than the kernel source
+
+	source "$build_include"
+	build_dir="$mk_build_dir"
+fi
+
+# This test requires kernel source and the *.gcda data therein
+# Locate the top level of the kernel source, and the net/rds
+# subfolder with the appropriate *.gcno object files
+ksrc_dir="$(realpath "$build_dir"/../../../../../)"
+kconfig="$ksrc_dir/.config"
+obj_dir="$ksrc_dir/net/rds"
+
+GCOV_CMD=gcov
+
+#check to see if the host has the required packages to generate a gcov report
+check_gcov_env()
+{
+	if ! which "$GCOV_CMD" > /dev/null 2>&1; then
+		echo "Warning: Could not find gcov. "
+		GENERATE_GCOV_REPORT=0
+		return
+	fi
+
+	# the gcov version must match the gcc version
+	GCC_VER=$(gcc -dumpfullversion)
+	GCOV_VER=$($GCOV_CMD -v | grep gcov | awk '{print $3}'| awk 'BEGIN {FS="-"}{print $1}')
+	if [ "$GCOV_VER" != "$GCC_VER" ]; then
+		#attempt to find a matching gcov version
+		GCOV_CMD=gcov-$(gcc -dumpversion)
+
+		if ! which "$GCOV_CMD" > /dev/null 2>&1; then
+			echo "Warning: Could not find an appropriate gcov installation. \
+				gcov version must match gcc version"
+			GENERATE_GCOV_REPORT=0
+			return
+		fi
+
+		#recheck version number of found gcov executable
+		GCOV_VER=$($GCOV_CMD -v | grep gcov | awk '{print $3}'| \
+			awk 'BEGIN {FS="-"}{print $1}')
+		if [ "$GCOV_VER" != "$GCC_VER" ]; then
+			echo "Warning: Could not find an appropriate gcov installation. \
+				gcov version must match gcc version"
+			GENERATE_GCOV_REPORT=0
+		else
+			echo "Warning: Mismatched gcc and gcov detected.  Using $GCOV_CMD"
+		fi
+	fi
+}
+
+# Check to see if the kconfig has the required configs to generate a coverage report
+check_gcov_conf()
+{
+	if ! grep -x "CONFIG_GCOV_PROFILE_RDS=y" "$kconfig" > /dev/null 2>&1; then
+		echo "INFO: CONFIG_GCOV_PROFILE_RDS should be enabled for coverage reports"
+		GENERATE_GCOV_REPORT=0
+	fi
+	if ! grep -x "CONFIG_GCOV_KERNEL=y" "$kconfig" > /dev/null 2>&1; then
+		echo "INFO: CONFIG_GCOV_KERNEL should be enabled for coverage reports"
+		GENERATE_GCOV_REPORT=0
+	fi
+	if grep -x "CONFIG_GCOV_PROFILE_ALL=y" "$kconfig" > /dev/null 2>&1; then
+		echo "INFO: CONFIG_GCOV_PROFILE_ALL should be disabled for coverage reports"
+		GENERATE_GCOV_REPORT=0
+	fi
+
+	if [ "$GENERATE_GCOV_REPORT" -eq 0 ]; then
+		echo "To enable gcov reports, please run "\
+			"\"tools/testing/selftests/net/rds/config.sh -g\" and rebuild the kernel"
+	else
+		# if we have the required kernel configs, proceed to check the environment to
+		# ensure we have the required gcov packages
+		check_gcov_env
+	fi
+}
+
+# Kselftest framework requirement - SKIP code is 4.
+check_conf_enabled() {
+	if ! grep -x "$1=y" "$kconfig" > /dev/null 2>&1; then
+		echo "selftests: [SKIP] This test requires $1 enabled"
+		echo "Please run tools/testing/selftests/net/rds/config.sh and rebuild the kernel"
+		exit 4
+	fi
+}
+check_conf_disabled() {
+	if grep -x "$1=y" "$kconfig" > /dev/null 2>&1; then
+		echo "selftests: [SKIP] This test requires $1 disabled"
+		echo "Please run tools/testing/selftests/net/rds/config.sh and rebuild the kernel"
+		exit 4
+	fi
+}
+check_conf() {
+	check_conf_enabled CONFIG_NET_SCH_NETEM
+	check_conf_enabled CONFIG_VETH
+	check_conf_enabled CONFIG_NET_NS
+	check_conf_enabled CONFIG_RDS_TCP
+	check_conf_enabled CONFIG_RDS
+	check_conf_disabled CONFIG_MODULES
+}
+
+check_env()
+{
+	if ! test -d "$obj_dir"; then
+		echo "selftests: [SKIP] This test requires a kernel source tree"
+		exit 4
+	fi
+	if ! test -e "$kconfig"; then
+		echo "selftests: [SKIP] This test requires a configured kernel source tree"
+		exit 4
+	fi
+	if ! which strace > /dev/null 2>&1; then
+		echo "selftests: [SKIP] Could not run test without strace"
+		exit 4
+	fi
+	if ! which tcpdump > /dev/null 2>&1; then
+		echo "selftests: [SKIP] Could not run test without tcpdump"
+		exit 4
+	fi
+
+	if ! which python3 > /dev/null 2>&1; then
+		echo "selftests: [SKIP] Could not run test without python3"
+		exit 4
+	fi
+
+	python_major=$(python3 -c "import sys; print(sys.version_info[0])")
+	python_minor=$(python3 -c "import sys; print(sys.version_info[1])")
+	if [[ python_major -lt 3 || ( python_major -eq 3 && python_minor -lt 9 ) ]] ; then
+		echo "selftests: [SKIP] Could not run test without at least python3.9"
+		python3 -V
+		exit 4
+	fi
+}
+
+LOG_DIR="$current_dir"/rds_logs
+PLOSS=0
+PCORRUPT=0
+PDUP=0
+GENERATE_GCOV_REPORT=1
+while getopts "d:l:c:u:" opt; do
+  case ${opt} in
+    d)
+      LOG_DIR=${OPTARG}
+      ;;
+    l)
+      PLOSS=${OPTARG}
+      ;;
+    c)
+      PCORRUPT=${OPTARG}
+      ;;
+    u)
+      PDUP=${OPTARG}
+      ;;
+    :)
+      echo "USAGE: run.sh [-d logdir] [-l packet_loss] [-c packet_corruption]" \
+           "[-u packet_duplcate] [-g]"
+      exit 1
+      ;;
+    ?)
+      echo "Invalid option: -${OPTARG}."
+      exit 1
+      ;;
+  esac
+done
+
+
+check_env
+check_conf
+check_gcov_conf
+
+
+rm -fr "$LOG_DIR"
+TRACE_FILE="${LOG_DIR}/rds-strace.txt"
+COVR_DIR="${LOG_DIR}/coverage/"
+mkdir -p  "$LOG_DIR"
+mkdir -p "$COVR_DIR"
+
+set +e
+echo running RDS tests...
+echo Traces will be logged to "$TRACE_FILE"
+rm -f "$TRACE_FILE"
+strace -T -tt -o "$TRACE_FILE" python3 "$(dirname "$0")/test.py" --timeout 400 -d "$LOG_DIR" \
+       -l "$PLOSS" -c "$PCORRUPT" -u "$PDUP"
+
+test_rc=$?
+dmesg > "${LOG_DIR}/dmesg.out"
+
+if [ "$GENERATE_GCOV_REPORT" -eq 1 ]; then
+       echo saving coverage data...
+       (set +x; cd /sys/kernel/debug/gcov; find ./* -name '*.gcda' | \
+       while read -r f
+       do
+               cat < "/sys/kernel/debug/gcov/$f" > "/$f"
+       done)
+
+       echo running gcovr...
+       gcovr -s --html-details --gcov-executable "$GCOV_CMD" --gcov-ignore-parse-errors \
+             -o "${COVR_DIR}/gcovr" "${ksrc_dir}/net/rds/"
+else
+       echo "Coverage report will be skipped"
+fi
+
+if [ "$test_rc" -eq 0 ]; then
+	echo "PASS: Test completed successfully"
+else
+	echo "FAIL: Test failed"
+fi
+
+exit "$test_rc"