From: Masami Hiramatsu (Google) <[email protected]> Add test cases for persistent ring buffer (reserve_mem= combined with trace_instance=) and backup instance (trace_instance=backup=boot_map).
These test cases verify: - persistent-01-reserve-mem: Memory reservation via reserve_mem= and trace_instance=boot_map@trace. Verifies trace data retention in the boot_map instance across guest crash/reboot via sysrq-trigger. - persistent-02-backup-instance: Backup instance creation via trace_instance=backup=boot_map. Verifies that previous boot trace log is preserved in the backup instance on the subsequent boot. These test cases specify '# REBOOT: 1' to enable multi-boot guest crash/reboot testing with doubled QEMU timeout. Assisted-by: Antigravity:gemini-3.6-flash Signed-off-by: Masami Hiramatsu (Google) <[email protected]> --- .../cmdlines/persistent-01-reserve-mem.cmdline | 1 + .../cmdlines/persistent-02-backup-instance.cmdline | 1 + .../boottime/tests/persistent-01-reserve-mem.sh | 28 ++++++++++++++ .../tests/persistent-02-backup-instance.sh | 40 ++++++++++++++++++++ 4 files changed, 70 insertions(+) create mode 100644 tools/testing/selftests/ftrace/boottime/cmdlines/persistent-01-reserve-mem.cmdline create mode 100644 tools/testing/selftests/ftrace/boottime/cmdlines/persistent-02-backup-instance.cmdline create mode 100644 tools/testing/selftests/ftrace/boottime/tests/persistent-01-reserve-mem.sh create mode 100644 tools/testing/selftests/ftrace/boottime/tests/persistent-02-backup-instance.sh diff --git a/tools/testing/selftests/ftrace/boottime/cmdlines/persistent-01-reserve-mem.cmdline b/tools/testing/selftests/ftrace/boottime/cmdlines/persistent-01-reserve-mem.cmdline new file mode 100644 index 000000000000..58e53f7edcd4 --- /dev/null +++ b/tools/testing/selftests/ftrace/boottime/cmdlines/persistent-01-reserve-mem.cmdline @@ -0,0 +1 @@ +reserve_mem=12M:4096:trace trace_instance=boot_map@trace diff --git a/tools/testing/selftests/ftrace/boottime/cmdlines/persistent-02-backup-instance.cmdline b/tools/testing/selftests/ftrace/boottime/cmdlines/persistent-02-backup-instance.cmdline new file mode 100644 index 000000000000..7b0713f550f8 --- /dev/null +++ b/tools/testing/selftests/ftrace/boottime/cmdlines/persistent-02-backup-instance.cmdline @@ -0,0 +1 @@ +reserve_mem=12M:4096:trace trace_instance=boot_map@trace trace_instance=backup=boot_map diff --git a/tools/testing/selftests/ftrace/boottime/tests/persistent-01-reserve-mem.sh b/tools/testing/selftests/ftrace/boottime/tests/persistent-01-reserve-mem.sh new file mode 100644 index 000000000000..49abaf518481 --- /dev/null +++ b/tools/testing/selftests/ftrace/boottime/tests/persistent-01-reserve-mem.sh @@ -0,0 +1,28 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2026, Google LLC. +# Check persistent ring buffer across guest crash/reboot +# REBOOT: 1 +TRACEDIR="/sys/kernel/tracing" + +if [ ! -f "$TRACEDIR/instances/boot_map/trace" ]; then + echo "FAIL: persistent trace instance boot_map/trace file missing" + exit 1 +fi + +# Check if Boot 1 marker was already written +if grep -q "BOOT1_MARKER" "$TRACEDIR/instances/boot_map/trace" 2>/dev/null; then + # Second boot: verify persistent ring buffer content from first boot + echo "PASS: persistent-01-reserve-mem" + exit 0 +fi + +# First boot: write marker to persistent buffer and trigger kernel crash/reboot +echo "BOOT1_MARKER" > "$TRACEDIR/instances/boot_map/trace_marker" +sync + +# Trigger reboot to restart into second boot +echo b > /proc/sysrq-trigger 2>/dev/null || echo c > /proc/sysrq-trigger 2>/dev/null || true +sleep 5 +echo "FAIL: reboot trigger failed on first boot" +exit 1 diff --git a/tools/testing/selftests/ftrace/boottime/tests/persistent-02-backup-instance.sh b/tools/testing/selftests/ftrace/boottime/tests/persistent-02-backup-instance.sh new file mode 100644 index 000000000000..0b2a2f03ce4f --- /dev/null +++ b/tools/testing/selftests/ftrace/boottime/tests/persistent-02-backup-instance.sh @@ -0,0 +1,40 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2026, Google LLC. +# Check persistent backup instance across guest crash/reboot +# REBOOT: 1 +TRACEDIR="/sys/kernel/tracing" + +# Ensure both boot_map/trace and backup/trace files exist +if [ ! -f "$TRACEDIR/instances/boot_map/trace" ]; then + echo "FAIL: boot_map/trace file missing" + exit 1 +fi + +if [ ! -f "$TRACEDIR/instances/backup/trace" ]; then + echo "FAIL: backup/trace file missing" + exit 1 +fi + +# Check if BOOT1_MARKER is in boot_map/trace (indicates second boot) +if grep -q "BOOT1_MARKER" "$TRACEDIR/instances/boot_map/trace" 2>/dev/null; then + # Second boot: verify BOOT1_MARKER was copied into backup/trace from Boot 1 + if grep -q "BOOT1_MARKER" "$TRACEDIR/instances/backup/trace" 2>/dev/null; then + echo "PASS: persistent-02-backup-instance" + exit 0 + else + echo "FAIL: BOOT1_MARKER found in boot_map/trace" \ + "but missing from backup/trace on second boot" + exit 1 + fi +fi + +# First boot: write BOOT1_MARKER to boot_map and reboot via sysrq-trigger +echo "BOOT1_MARKER" > "$TRACEDIR/instances/boot_map/trace_marker" +sync + +# Trigger reboot to restart into second boot +echo b > /proc/sysrq-trigger 2>/dev/null || echo c > /proc/sysrq-trigger 2>/dev/null || true +sleep 5 +echo "FAIL: reboot trigger failed on first boot" +exit 1
