new file mode 100644
@@ -0,0 +1,17 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Snapshot and tracing_cpumask
+# requires: trace_marker tracing_cpumask snapshot
+# flags: instance
+
+# This testcase is constrived to reproduce a problem that the cpu buffers
+# become unavailable which is due to 'record_disabled' of array_buffer and
+# max_buffer being messed up.
+
+ORIG_CPUMASK=`cat tracing_cpumask`
+echo 0 > tracing_cpumask
+echo 1 > snapshot
+echo ${ORIG_CPUMASK} > tracing_cpumask
+echo "test input 1" > trace_marker
+grep -q "test input 1" trace
+exit 0
This testcase is constrived to reproduce a problem that the cpu buffers become unavailable which is due to 'record_disabled' of array_buffer and max_buffer being messed up. Local test result after bugfix: # ./ftracetest test.d/00basic/snapshot1.tc === Ftrace unit tests === [1] Snapshot and tracing_cpumask [PASS] [2] (instance) Snapshot and tracing_cpumask [PASS] # of passed: 2 # of failed: 0 # of unresolved: 0 # of untested: 0 # of unsupported: 0 # of xfailed: 0 # of undefined(test bug): 0 Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com> --- .../ftrace/test.d/00basic/snapshot1.tc | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) create mode 100644 tools/testing/selftests/ftrace/test.d/00basic/snapshot1.tc