KVM: selftests: Verify stats fd can be dup()'d and read

Expand the binary stats test to verify that a stats fd can be dup()'d
and read, to (very) roughly simulate userspace passing around the file.
Adding the dup() test is primarily an intermediate step towards verifying
that userspace can read VM/vCPU stats before _and_ after userspace closes
its copy of the VM fd; the dup() test itself is only mildly interesting.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230711230131.648752-7-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Sean Christopherson 2023-07-11 16:01:30 -07:00 committed by Paolo Bonzini
parent 47d1be8a78
commit 65f1f57f35
1 changed files with 7 additions and 1 deletions

View File

@ -232,17 +232,23 @@ int main(int argc, char *argv[])
}
/*
* Check stats read for every VM and vCPU, with a variety of testcases.
* Check stats read for every VM and vCPU, with a variety of flavors.
* Note, stats_test() closes the passed in stats fd.
*/
for (i = 0; i < max_vm; ++i) {
/*
* Verify that creating multiple userspace references to a
* single stats file works and doesn't cause explosions.
*/
vm_stats_fds = vm_get_stats_fd(vms[i]);
stats_test(dup(vm_stats_fds));
/* Verify userspace can instantiate multiple stats files. */
stats_test(vm_get_stats_fd(vms[i]));
for (j = 0; j < max_vcpu; ++j) {
vcpu_stats_fds[j] = vcpu_get_stats_fd(vcpus[i * max_vcpu + j]);
stats_test(dup(vcpu_stats_fds[j]));
stats_test(vcpu_get_stats_fd(vcpus[i * max_vcpu + j]));
}