1This directory contains a mix of tests integrated with kselftest and
2standalone stress tests.
3
4kselftest tests
5===============
6
7sve-probe-vls - Checks the SVE vector length enumeration interface
8sve-ptrace - Checks the SVE ptrace interface
9
10Running the non-kselftest tests
11===============================
12
13sve-stress performs an SVE context switch stress test, as described
14below.
15
16(The fpsimd-stress test works the same way; just substitute "fpsimd" for
17"sve" in the following commands.)
18
19
20The test runs until killed by the user.
21
22If no context switch error was detected, you will see output such as
23the following:
24
25$ ./sve-stress
26(wait for some time)
27^C
28Vector length: 512 bits
29PID: 1573
30Terminated by signal 15, no error, iterations=9467, signals=1014
31Vector length: 512 bits
32PID: 1575
33Terminated by signal 15, no error, iterations=9448, signals=1028
34Vector length: 512 bits
35PID: 1577
36Terminated by signal 15, no error, iterations=9436, signals=1039
37Vector length: 512 bits
38PID: 1579
39Terminated by signal 15, no error, iterations=9421, signals=1039
40Vector length: 512 bits
41PID: 1581
42Terminated by signal 15, no error, iterations=9403, signals=1039
43Vector length: 512 bits
44PID: 1583
45Terminated by signal 15, no error, iterations=9385, signals=1036
46Vector length: 512 bits
47PID: 1585
48Terminated by signal 15, no error, iterations=9376, signals=1039
49Vector length: 512 bits
50PID: 1587
51Terminated by signal 15, no error, iterations=9361, signals=1039
52Vector length: 512 bits
53PID: 1589
54Terminated by signal 15, no error, iterations=9350, signals=1039
55
56
57If an error was detected, details of the mismatch will be printed
58instead of "no error".
59
60Ideally, the test should be allowed to run for many minutes or hours
61to maximise test coverage.
62
63
64KVM stress testing
65==================
66
67To try to reproduce the bugs that we have been observing, sve-stress
68should be run in parallel in two KVM guests, while simultaneously
69running on the host.
70
711) Start 2 guests, using the following command for each:
72
73$ lkvm run --console=virtio -pconsole=hvc0 --sve Image
74
75(Depending on the hardware GIC implementation, you may also need
76--irqchip=gicv3. New kvmtool defaults to that if appropriate, but I
77can't remember whether my branch is new enough for that. Try without
78the option first.)
79
80Kvmtool occupies the terminal until you kill it (Ctrl+A x),
81or until the guest terminates. It is therefore recommended to run
82each instance in separate terminal (use screen or ssh etc.) This
83allows multiple guests to be run in parallel while running other
84commands on the host.
85
86Within the guest, the host filesystem is accessible, mounted on /host.
87
882) Run the sve-stress on *each* guest with the Vector-Length set to 32:
89guest$ ./vlset --inherit 32 ./sve-stress
90
913) Run the sve-stress on the host with the maximum Vector-Length:
92host$ ./vlset --inherit --max ./sve-stress
93
94
95Again, the test should be allowed to run for many minutes or hours to
96maximise test coverage.
97
98If no error is detected, you will see output from each sve-stress
99instance similar to that illustrated above; otherwise details of the
100observed mismatches will be printed.
101