From 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 12:05:51 +0200 Subject: Adding upstream version 5.10.209. Signed-off-by: Daniel Baumann --- tools/testing/selftests/arm64/fp/README | 100 ++++++++++++++++++++++++++++++++ 1 file changed, 100 insertions(+) create mode 100644 tools/testing/selftests/arm64/fp/README (limited to 'tools/testing/selftests/arm64/fp/README') diff --git a/tools/testing/selftests/arm64/fp/README b/tools/testing/selftests/arm64/fp/README new file mode 100644 index 000000000..03e3dad86 --- /dev/null +++ b/tools/testing/selftests/arm64/fp/README @@ -0,0 +1,100 @@ +This directory contains a mix of tests integrated with kselftest and +standalone stress tests. + +kselftest tests +=============== + +sve-probe-vls - Checks the SVE vector length enumeration interface +sve-ptrace - Checks the SVE ptrace interface + +Running the non-kselftest tests +=============================== + +sve-stress performs an SVE context switch stress test, as described +below. + +(The fpsimd-stress test works the same way; just substitute "fpsimd" for +"sve" in the following commands.) + + +The test runs until killed by the user. + +If no context switch error was detected, you will see output such as +the following: + +$ ./sve-stress +(wait for some time) +^C +Vector length: 512 bits +PID: 1573 +Terminated by signal 15, no error, iterations=9467, signals=1014 +Vector length: 512 bits +PID: 1575 +Terminated by signal 15, no error, iterations=9448, signals=1028 +Vector length: 512 bits +PID: 1577 +Terminated by signal 15, no error, iterations=9436, signals=1039 +Vector length: 512 bits +PID: 1579 +Terminated by signal 15, no error, iterations=9421, signals=1039 +Vector length: 512 bits +PID: 1581 +Terminated by signal 15, no error, iterations=9403, signals=1039 +Vector length: 512 bits +PID: 1583 +Terminated by signal 15, no error, iterations=9385, signals=1036 +Vector length: 512 bits +PID: 1585 +Terminated by signal 15, no error, iterations=9376, signals=1039 +Vector length: 512 bits +PID: 1587 +Terminated by signal 15, no error, iterations=9361, signals=1039 +Vector length: 512 bits +PID: 1589 +Terminated by signal 15, no error, iterations=9350, signals=1039 + + +If an error was detected, details of the mismatch will be printed +instead of "no error". + +Ideally, the test should be allowed to run for many minutes or hours +to maximise test coverage. + + +KVM stress testing +================== + +To try to reproduce the bugs that we have been observing, sve-stress +should be run in parallel in two KVM guests, while simultaneously +running on the host. + +1) Start 2 guests, using the following command for each: + +$ lkvm run --console=virtio -pconsole=hvc0 --sve Image + +(Depending on the hardware GIC implementation, you may also need +--irqchip=gicv3. New kvmtool defaults to that if appropriate, but I +can't remember whether my branch is new enough for that. Try without +the option first.) + +Kvmtool occupies the terminal until you kill it (Ctrl+A x), +or until the guest terminates. It is therefore recommended to run +each instance in separate terminal (use screen or ssh etc.) This +allows multiple guests to be run in parallel while running other +commands on the host. + +Within the guest, the host filesystem is accessible, mounted on /host. + +2) Run the sve-stress on *each* guest with the Vector-Length set to 32: +guest$ ./vlset --inherit 32 ./sve-stress + +3) Run the sve-stress on the host with the maximum Vector-Length: +host$ ./vlset --inherit --max ./sve-stress + + +Again, the test should be allowed to run for many minutes or hours to +maximise test coverage. + +If no error is detected, you will see output from each sve-stress +instance similar to that illustrated above; otherwise details of the +observed mismatches will be printed. -- cgit v1.2.3