KVM: selftests: Remove redundant newlines

TEST_* functions append their own newline. Remove newlines from
TEST_* callsites to avoid extra newlines in output.

Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20231206170241.82801-8-ajones@ventanamicro.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

KVM: selftests: Have perf_test_util signal when to stop vCPUs

Signal that a test run is complete through perf_test_args instead of
having tests open code a similar solution. Ensure that the field resets
to false at the beginning of a test run as the structure is reused
between test runs, eliminating a couple of bugs:

access_tracking_perf_test hangs indefinitely on a subsequent test run,
as 'done' remains true. The bug doesn't amount to much right now, as x86
supports a single guest mode. However, this is a precondition of
enabling the test for other architectures with >1 guest mode, like
arm64.

memslot_modification_stress_test has the exact opposite problem, where
subsequent test runs complete immediately as 'run_vcpus' remains false.

Co-developed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
[oliver: added commit message, preserve spin_wait_for_next_iteration()]
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221118211503.4049023-2-oliver.upton@linux.dev

KVM: selftests: Rename perf_test_util symbols to memstress

Replace the perf_test_ prefix on symbol names with memstress_ to match
the new file name.

"memstress" better describes the functionality proveded by this library,
which is to provide functionality for creating and running a VM that
stresses VM memory by reading and writing to guest memory on all vCPUs
in parallel.

"memstress" also contains the same number of chracters as "perf_test",
making it a drop-in replacement in symbols, e.g. function names, without
impacting line lengths. Also the lack of underscore between "mem" and
"stress" makes it clear "memstress" is a noun.

Signed-off-by: David Matlack <dmatlack@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221012165729.3505266-4-dmatlack@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

KVM: selftests: Rename perf_test_util.[ch] to memstress.[ch]

Rename the perf_test_util.[ch] files to memstress.[ch]. Symbols are
renamed in the following commit to reduce the amount of churn here in
hopes of playiing nice with git's file rename detection.

The name "memstress" was chosen to better describe the functionality
proveded by this library, which is to create and run a VM that
reads/writes to guest memory on all vCPUs in parallel.

"memstress" also contains the same number of chracters as "perf_test",
making it a drop-in replacement in symbols, e.g. function names, without
impacting line lengths. Also the lack of underscore between "mem" and
"stress" makes it clear "memstress" is a noun.

Signed-off-by: David Matlack <dmatlack@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221012165729.3505266-2-dmatlack@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

KVM: selftests: Add atoi_positive() and atoi_non_negative() for input validation

Many KVM selftests take command line arguments which are supposed to be
positive (>0) or non-negative (>=0). Some tests do these validation and
some missed adding the check.

Add atoi_positive() and atoi_non_negative() to validate inputs in
selftests before proceeding to use those values.

Signed-off-by: Vipin Sharma <vipinsh@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221103191719.1559407-7-vipinsh@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

KVM: selftests: Shorten the test args in memslot_modification_stress_test.c

Change test args memslot_modification_delay and nr_memslot_modifications
to delay and nr_iterations for simplicity.

Signed-off-by: Vipin Sharma <vipinsh@google.com>
Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221103191719.1559407-6-vipinsh@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

KVM: selftests: Add atoi_paranoid() to catch errors missed by atoi()

atoi() doesn't detect errors. There is no way to know that a 0 return
is correct conversion or due to an error.

Introduce atoi_paranoid() to detect errors and provide correct
conversion. Replace all atoi() calls with atoi_paranoid().

Signed-off-by: Vipin Sharma <vipinsh@google.com>
Suggested-by: David Matlack <dmatlack@google.com>
Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221103191719.1559407-4-vipinsh@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

KVM: selftests: Fix number of pages for memory slot in memslot_modification_stress_test

It's required by vm_userspace_mem_region_add() that memory size
should be aligned to host page size. However, one guest page is
provided by memslot_modification_stress_test. It triggers failure
in the scenario of 64KB-page-size-host and 4KB-page-size-guest,
as the following messages indicate.

# ./memslot_modification_stress_test
Testing guest mode: PA-bits:40, VA-bits:48, 4K pages
guest physical test memory: [0xffbfff0000, 0xffffff0000)
Finished creating vCPUs
Started all vCPUs
==== Test Assertion Failure ====
lib/kvm_util.c:824: vm_adjust_num_guest_pages(vm->mode, npages) == npages
pid=5712 tid=5712 errno=0 - Success
1 0x0000000000404eeb: vm_userspace_mem_region_add at kvm_util.c:822
2 0x0000000000401a5b: add_remove_memslot at memslot_modification_stress_test.c:82
3 (inlined by) run_test at memslot_modification_stress_test.c:110
4 0x0000000000402417: for_each_guest_mode at guest_modes.c:100
5 0x00000000004016a7: main at memslot_modification_stress_test.c:187
6 0x0000ffffb8cd4383: ?? ??:0
7 0x0000000000401827: _start at :?
Number of guest pages is not compatible with the host. Try npages=16

Fix the issue by providing 16 guest pages to the memory slot for this
particular combination of 64KB-page-size-host and 4KB-page-size-guest
on aarch64.

Fixes: ef4c9f4f65462 ("KVM: selftests: Fix 32-bit truncation of vm_get_max_gfn()")
Signed-off-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221013063020.201856-1-gshan@redhat.com

KVM: selftests: Open code and drop 'struct kvm_vm' accessors

Drop a variety of 'struct kvm_vm' accessors that wrap a single variable
now that tests can simply reference the variable directly.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Purge vm+vcpu_id == vcpu silliness

Take a vCPU directly instead of a VM+vcpu pair in all vCPU-scoped helpers
and ioctls.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Stop conflating vCPU index and ID in perf tests

Track vCPUs by their 'struct kvm_vcpu' object, and stop assuming that a
vCPU's ID is the same as its index when referencing a vCPU's metadata.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Use perf_test_destroy_vm in memslot_modification_stress_test

Change memslot_modification_stress_test to use perf_test_destroy_vm
instead of manually calling ucall_uninit and kvm_vm_free.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
Reviewed-by: Ben Gardon <bgardon@google.com>
Message-Id: <20211111001257.1446428-5-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Move vCPU thread creation and joining to common helpers

Move vCPU thread creation and joining to common helper functions. This
is in preparation for the next commit which ensures that all vCPU
threads are fully created before entering guest mode on any one
vCPU.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
Reviewed-by: Ben Gardon <bgardon@google.com>
Message-Id: <20211111001257.1446428-3-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Sync perf_test_args to guest during VM creation

Copy perf_test_args to the guest during VM creation instead of relying on
the caller to do so at their leisure. Ideally, tests wouldn't even be
able to modify perf_test_args, i.e. they would have no motivation to do
the sync, but enforcing that is arguably a net negative for readability.

No functional change intended.

[Set wr_fract=1 by default and add helper to override it since the new
access_tracking_perf_test needs to set it dynamically.]

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Reviewed-by: Ben Gardon <bgardon@google.com>
Message-Id: <20211111000310.1435032-13-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Fill per-vCPU struct during "perf_test" VM creation

Fill the per-vCPU args when creating the perf_test VM instead of having
the caller do so. This helps ensure that any adjustments to the number
of pages (and thus vcpu_memory_bytes) are reflected in the per-VM args.
Automatically filling the per-vCPU args will also allow a future patch
to do the sync to the guest during creation.

Signed-off-by: Sean Christopherson <seanjc@google.com>
[Updated access_tracking_perf_test as well.]
Signed-off-by: David Matlack <dmatlack@google.com>
Reviewed-by: Ben Gardon <bgardon@google.com>
Message-Id: <20211111000310.1435032-12-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Move per-VM GPA into perf_test_args

Move the per-VM GPA into perf_test_args instead of storing it as a
separate global variable. It's not obvious that guest_test_phys_mem
holds a GPA, nor that it's connected/coupled with per_vcpu->gpa.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Ben Gardon <bgardon@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20211111000310.1435032-9-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Move vcpu_args_set into perf_test_util

perf_test_util is used to set up KVM selftests where vCPUs touch a
region of memory. The guest code is implemented in perf_test_util.c (not
the calling selftests). The guest code requires a 1 parameter, the
vcpuid, which has to be set by calling vcpu_args_set(vm, vcpu_id, 1,
vcpu_id).

Today all of the selftests that use perf_test_util are making this call.
Instead, perf_test_util should just do it. This will save some code but
more importantly prevents mistakes since totally non-obvious that this
needs to be called and failing to do so results in vCPUs not accessing
the right regions of memory.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20210805172821.2622793-1-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Support multiple slots in dirty_log_perf_test

Introduce a new option to dirty_log_perf_test: -x number_of_slots. This
causes the test to attempt to split the region of memory into the given
number of slots. If the region cannot be evenly divided, the test will
fail.

This allows testing with more than one slot and therefore measure how
performance scales with the number of memslots.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20210804222844.1419481-8-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Fix 32-bit truncation of vm_get_max_gfn()

vm_get_max_gfn() casts vm->max_gfn from a uint64_t to an unsigned int,
which causes the upper 32-bits of the max_gfn to get truncated.

Nobody noticed until now likely because vm_get_max_gfn() is only used
as a mechanism to create a memslot in an unused region of the guest
physical address space (the top), and the top of the 32-bit physical
address space was always good enough.

This fix reveals a bug in memslot_modification_stress_test which was
trying to create a dummy memslot past the end of guest physical memory.
Fix that by moving the dummy memslot lower.

Fixes: 52200d0d944e ("KVM: selftests: Remove duplicate guest mode handling")
Reviewed-by: Venkatesh Srinivas <venkateshs@chromium.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20210521173828.1180619-1-dmatlack@google.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Add backing src parameter to dirty_log_perf_test

Add a parameter to control the backing memory type for
dirty_log_perf_test so that the test can be run with hugepages.

To: linux-kselftest@vger.kernel.org
CC: Peter Xu <peterx@redhat.com>
CC: Andrew Jones <drjones@redhat.com>
CC: Thomas Huth <thuth@redhat.com>
Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20210202185734.1680553-28-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Add memslot modification stress test

Add a memslot modification stress test in which a memslot is repeatedly
created and removed while vCPUs access memory in another memslot. Most
userspaces do not create or remove memslots on running VMs which makes
it hard to test races in adding and removing memslots without a
dedicated test. Adding and removing a memslot also has the effect of
tearing down the entire paging structure, which leads to more page
faults and pressure on the page fault handling path than a one-and-done
memory population test.

Reviewed-by: Jacob Xu <jacobhxu@google.com>

Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20210112214253.463999-7-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>