And for 4.4.0-111 too:

ubuntu@kernel01:~/cking$ uname -a
Linux kernel01 4.4.0-111-generic #134-Ubuntu SMP Mon Jan 15 14:49:29 UTC 2018 s390x s390x s390x GNU/Linux
ubuntu@kernel01:~/cking$ sudo autotest/client/autotest-local autotest/client/tests/ubuntu_lttng_smoke_test/control 
04:31:41 INFO | Writing results to /home/ubuntu/cking/autotest/client/results/default
04:31:41 INFO | START	----	----	timestamp=1517304701	localtime=Jan 30 04:31:41	
04:31:41 INFO | 	START	ubuntu_lttng_smoke_test.lttng-smoke-test	ubuntu_lttng_smoke_test.lttng-smoke-test	timestamp=1517304701	localtime=Jan 30 04:31:41	
04:31:46 ERROR| [stderr] [warning] Tracer discarded 4316 events between [04:31:43.716983490] and [04:31:43.786991226] in trace UUID 92f5c9ff926f97469351d5fcfe55d3f, at path: "/tmp/lttng-kernel-trace-3597-session/kernel", within stream id 0, at relative path: "channel0_6". You should consider recording a new trace with larger buffers or with fewer events enabled.
04:31:47 ERROR| [stderr] [warning] Tracer discarded 828 events between [04:31:44.119735735] and [04:31:44.189824803] in trace UUID 92f5c9ff926f97469351d5fcfe55d3f, at path: "/tmp/lttng-kernel-trace-3597-session/kernel", within stream id 0, at relative path: "channel0_3". You should consider recording a new trace with larger buffers or with fewer events enabled.
04:31:47 INFO | == lttng smoke test of session create/destroy ==
04:31:47 INFO | Session test-kernel-session created.
04:31:47 INFO | Traces will be written in /tmp/lttng-kernel-trace-3597-session
04:31:47 INFO | PASSED (lttng create)
04:31:47 INFO | Session test-kernel-session destroyed
04:31:47 INFO | PASSED (lttng destroy)
04:31:47 INFO |  
04:31:47 INFO | == lttng smoke test list kernel events ==
04:31:47 INFO | PASSED (lttng list --kernel)
04:31:47 INFO |  
04:31:47 INFO | lttng smoke test trace open/close system calls SKIPPED for s390x
04:31:47 INFO |  
04:31:47 INFO | == lttng smoke test trace context switches ==
04:31:47 INFO | Session test-kernel-session created.
04:31:47 INFO | Traces will be written in /tmp/lttng-kernel-trace-3597-session
04:31:47 INFO | PASSED (lttng create)
04:31:47 INFO | Kernel event sched_switch created in channel channel0
04:31:47 INFO | PASSED (lttng enable-event)
04:31:47 INFO | Tracing started for session test-kernel-session
04:31:47 INFO | PASSED (lttng start)
04:31:47 INFO | Waiting for data availability.
04:31:47 INFO | Tracing stopped for session test-kernel-session
04:31:47 INFO | PASSED (lttng stop)
04:31:47 INFO | Session test-kernel-session destroyed
04:31:47 INFO | PASSED (lttng destroy)
04:31:47 INFO | Found 30808 dd and 59265 context switches
04:31:47 INFO | PASSED (simple system call tracing with babeltrace)
04:31:47 INFO |  
04:31:47 INFO | Summary: 8 passed, 0 failed
04:31:47 INFO | 		GOOD	ubuntu_lttng_smoke_test.lttng-smoke-test	ubuntu_lttng_smoke_test.lttng-smoke-test	timestamp=1517304707	localtime=Jan 30 04:31:47	completed successfully
04:31:47 INFO | 	END GOOD	ubuntu_lttng_smoke_test.lttng-smoke-test	ubuntu_lttng_smoke_test.lttng-smoke-test	timestamp=1517304707	localtime=Jan 30 04:31:47	
04:31:47 INFO | END GOOD	----	----	timestamp=1517304707	localtime=Jan 30 04:31:47	
04:31:47 INFO | Report successfully generated at /home/ubuntu/cking/autotest/client/results/default/job_report.html