linux-stable.git/tools/testing/selftests/kvm, branch v5.10

selftests: kvm/set_memory_region_test: Fix race in move region test

2020-12-03T17:38:58+00:00

The current memory region move test correctly handles the situation that
the second (realigning) memslot move operation would temporarily trigger
MMIO until it completes, however it does not handle the case in which the
first (misaligning) move operation does this, too.
This results in false test assertions in case it does so.

Fix this by handling temporary MMIO from the first memslot move operation
in the test guest code, too.

Fixes: 8a0639fe9201 ("KVM: sefltests: Add explicit synchronization to move mem region test")
Signed-off-by: Maciej S. Szmigiero 
Message-Id: <0fdddb94bb0e31b7da129a809a308d91c10c0b5e.1606941224.git.maciej.szmigiero@oracle.com>
Signed-off-by: Paolo Bonzini

KVM: selftests: allow two iterations of dirty_log_perf_test

2020-11-09T14:45:17+00:00

Even though one iteration is not enough for the dirty log performance
test (due to the cost of building page tables, zeroing memory etc.)
two is okay and it is the default.  Without this patch,
"./dirty_log_perf_test" without any further arguments fails.

Cc: Ben Gardon 
Signed-off-by: Paolo Bonzini

KVM: selftests: Introduce the dirty log perf test

2020-11-08T11:04:08+00:00

The dirty log perf test will time verious dirty logging operations
(enabling dirty logging, dirtying memory, getting the dirty log,
clearing the dirty log, and disabling dirty logging) in order to
quantify dirty logging performance. This test can be used to inform
future performance improvements to KVM's dirty logging infrastructure.

This series was tested by running the following invocations on an Intel
Skylake machine:
dirty_log_perf_test -b 20m -i 100 -v 64
dirty_log_perf_test -b 20g -i 5 -v 4
dirty_log_perf_test -b 4g -i 5 -v 32
demand_paging_test -b 20m -v 64
demand_paging_test -b 20g -v 4
demand_paging_test -b 4g -v 32
All behaved as expected.

Signed-off-by: Ben Gardon 
Message-Id: <20201027233733.1484855-6-bgardon@google.com>
Signed-off-by: Paolo Bonzini

KVM: selftests: Make the number of vcpus global

2020-11-08T11:04:03+00:00

We also check the input number of vcpus against the maximum supported.

Signed-off-by: Andrew Jones 
Message-Id: <20201104212357.171559-8-drjones@redhat.com>
Signed-off-by: Paolo Bonzini

KVM: selftests: Make the per vcpu memory size global

2020-11-08T11:03:55+00:00

Rename vcpu_memory_bytes to something with "percpu" in it
in order to be less ambiguous. Also make it global to
simplify things.

Signed-off-by: Andrew Jones 
Message-Id: <20201104212357.171559-7-drjones@redhat.com>
Signed-off-by: Paolo Bonzini

KVM: selftests: Drop pointless vm_create wrapper

2020-11-08T11:03:36+00:00

Signed-off-by: Andrew Jones 
Message-Id: <20201104212357.171559-3-drjones@redhat.com>
Signed-off-by: Paolo Bonzini

KVM: selftests: Add wrfract to common guest code

2020-11-08T11:03:35+00:00

Wrfract will be used by the dirty logging perf test introduced later in
this series to dirty memory sparsely.

This series was tested by running the following invocations on an Intel
Skylake machine:
dirty_log_perf_test -b 20m -i 100 -v 64
dirty_log_perf_test -b 20g -i 5 -v 4
dirty_log_perf_test -b 4g -i 5 -v 32
demand_paging_test -b 20m -v 64
demand_paging_test -b 20g -v 4
demand_paging_test -b 4g -v 32
All behaved as expected.

Signed-off-by: Ben Gardon 
Message-Id: <20201027233733.1484855-5-bgardon@google.com>
Signed-off-by: Paolo Bonzini

KVM: selftests: Simplify demand_paging_test with timespec_diff_now

2020-11-08T11:03:35+00:00

Add a helper function to get the current time and return the time since
a given start time. Use that function to simplify the timekeeping in the
demand paging test.

This series was tested by running the following invocations on an Intel
Skylake machine:
dirty_log_perf_test -b 20m -i 100 -v 64
dirty_log_perf_test -b 20g -i 5 -v 4
dirty_log_perf_test -b 4g -i 5 -v 32
demand_paging_test -b 20m -v 64
demand_paging_test -b 20g -v 4
demand_paging_test -b 4g -v 32
All behaved as expected.

Signed-off-by: Ben Gardon 
Message-Id: <20201027233733.1484855-4-bgardon@google.com>
Signed-off-by: Paolo Bonzini

KVM: selftests: Remove address rounding in guest code

2020-11-08T11:03:34+00:00

Rounding the address the guest writes to a host page boundary
will only have an effect if the host page size is larger than the guest
page size, but in that case the guest write would still go to the same
host page. There's no reason to round the address down, so remove the
rounding to simplify the demand paging test.

This series was tested by running the following invocations on an Intel
Skylake machine:
dirty_log_perf_test -b 20m -i 100 -v 64
dirty_log_perf_test -b 20g -i 5 -v 4
dirty_log_perf_test -b 4g -i 5 -v 32
demand_paging_test -b 20m -v 64
demand_paging_test -b 20g -v 4
demand_paging_test -b 4g -v 32
All behaved as expected.

Signed-off-by: Ben Gardon 
Message-Id: <20201027233733.1484855-3-bgardon@google.com>
Signed-off-by: Paolo Bonzini

KVM: selftests: Factor code out of demand_paging_test

2020-11-08T11:03:34+00:00

Much of the code in demand_paging_test can be reused by other, similar
multi-vCPU-memory-touching-perfromance-tests. Factor that common code
out for reuse.

No functional change expected.

This series was tested by running the following invocations on an Intel
Skylake machine:
dirty_log_perf_test -b 20m -i 100 -v 64
dirty_log_perf_test -b 20g -i 5 -v 4
dirty_log_perf_test -b 4g -i 5 -v 32
demand_paging_test -b 20m -v 64
demand_paging_test -b 20g -v 4
demand_paging_test -b 4g -v 32
All behaved as expected.

Signed-off-by: Ben Gardon 
Message-Id: <20201027233733.1484855-2-bgardon@google.com>
Signed-off-by: Paolo Bonzini