perf test kvm: Add some basic perf kvm test coverage

Setup qemu with KVM then run kvm stat and some host
recording/reporting/build-id tests.

Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>

diff --git a/tools/perf/tests/shell/kvm.sh b/tools/perf/tests/shell/kvm.sh
new file mode 100755 (executable)
index 0000000..2fafde1
--- /dev/null
+++ b/tools/perf/tests/shell/kvm.sh
@@ -0,0 +1,154 @@
+#!/bin/bash
+# perf kvm tests
+# SPDX-License-Identifier: GPL-2.0
+
+set -e
+
+err=0
+perfdata=$(mktemp /tmp/__perf_kvm_test.perf.data.XXXXX)
+qemu_pid_file=$(mktemp /tmp/__perf_kvm_test.qemu.pid.XXXXX)
+
+cleanup() {
+       rm -f "${perfdata}"
+       if [ -f "${qemu_pid_file}" ]; then
+               if [ -s "${qemu_pid_file}" ]; then
+                       qemu_pid=$(cat "${qemu_pid_file}")
+                       if [ -n "${qemu_pid}" ]; then
+                               kill "${qemu_pid}" 2>/dev/null || true
+                       fi
+               fi
+               rm -f "${qemu_pid_file}"
+       fi
+       trap - EXIT TERM INT
+}
+
+trap_cleanup() {
+       echo "Unexpected signal in ${FUNCNAME[1]}"
+       cleanup
+       exit 1
+}
+trap trap_cleanup EXIT TERM INT
+
+skip() {
+       echo "Skip: $1"
+       cleanup
+       exit 2
+}
+
+test_kvm_stat() {
+       echo "Testing perf kvm stat"
+
+       echo "Recording kvm events for pid ${qemu_pid}..."
+       if ! perf kvm stat record -p "${qemu_pid}" -o "${perfdata}" sleep 1; then
+               echo "Failed to record kvm events"
+               err=1
+               return
+       fi
+
+       echo "Reporting kvm events..."
+       if ! perf kvm -i "${perfdata}" stat report 2>&1 | grep -q "VM-EXIT"; then
+               echo "Failed to find VM-EXIT in report"
+               perf kvm -i "${perfdata}" stat report 2>&1
+               err=1
+               return
+       fi
+
+       echo "perf kvm stat test [Success]"
+}
+
+test_kvm_record_report() {
+       echo "Testing perf kvm record/report"
+
+       echo "Recording kvm profile for pid ${qemu_pid}..."
+       # Use --host to avoid needing guest symbols/mounts for this simple test
+       # We just want to verify the command runs and produces data
+       # We run in background and kill it because 'perf kvm record' appends options
+       # after the command, which breaks 'sleep' (e.g. it gets '-e cycles').
+       perf kvm --host record -p "${qemu_pid}" -o "${perfdata}" &
+       rec_pid=$!
+       sleep 1
+       kill -INT "${rec_pid}"
+       wait "${rec_pid}" || true
+
+       echo "Reporting kvm profile..."
+       # Check for some standard output from report
+       if ! perf kvm -i "${perfdata}" report --stdio 2>&1 | grep -q "Event count"; then
+               echo "Failed to report kvm profile"
+               perf kvm -i "${perfdata}" report --stdio 2>&1
+               err=1
+               return
+       fi
+
+       echo "perf kvm record/report test [Success]"
+}
+
+test_kvm_buildid_list() {
+       echo "Testing perf kvm buildid-list"
+
+       # We reuse the perf.data from the previous record test
+       if ! perf kvm --host -i "${perfdata}" buildid-list 2>&1 | grep -q "."; then
+               echo "Failed to list buildids"
+               perf kvm --host -i "${perfdata}" buildid-list 2>&1
+               err=1
+               return
+       fi
+
+       echo "perf kvm buildid-list test [Success]"
+}
+
+setup_qemu() {
+       # Find qemu
+       if [ "$(uname -m)" = "x86_64" ]; then
+               qemu="qemu-system-x86_64"
+       elif [ "$(uname -m)" = "aarch64" ]; then
+               qemu="qemu-system-aarch64"
+       elif [ "$(uname -m)" = "s390x" ]; then
+               qemu="qemu-system-s390x"
+       elif [ "$(uname -m)" = "ppc64le" ]; then
+               qemu="qemu-system-ppc64"
+       else
+               qemu="qemu-system-$(uname -m)"
+       fi
+
+       if ! which -s "$qemu"; then
+               skip "$qemu not found"
+       fi
+
+       if [ ! -r /dev/kvm ] || [ ! -w /dev/kvm ]; then
+               skip "/dev/kvm not accessible"
+       fi
+
+       if ! perf kvm stat record -a sleep 0.01 >/dev/null 2>&1; then
+               skip "No permission to record kvm events"
+       fi
+
+       echo "Starting $qemu..."
+       # Start qemu in background, detached, with pidfile
+       # We use -display none -daemonize and a monitor to keep it alive/controllable if needed
+       # We don't need a real kernel, just KVM active.
+       if ! $qemu -enable-kvm -display none -daemonize -pidfile "${qemu_pid_file}" -monitor none; then
+               echo "Failed to start qemu"
+               err=1
+               return
+       fi
+
+       # Wait a bit for qemu to start
+       sleep 1
+       qemu_pid=$(cat "${qemu_pid_file}")
+
+       if ! kill -0 "${qemu_pid}" 2>/dev/null; then
+               echo "Qemu process failed to stay alive"
+               err=1
+               return
+       fi
+}
+
+setup_qemu
+if [ $err -eq 0 ]; then
+       test_kvm_stat
+       test_kvm_record_report
+       test_kvm_buildid_list
+fi
+
+cleanup
+exit $err