Re: [PATCH v1 1/3] KVM: selftests: memstress: Add option to enable dirty-ring on VM creation

[Sean Christopherson <seanjc@google.com>]

On Tue, Sep 29, 2026, Leonardo Bras wrote:
> Dirty-ring should be enabled after the VM is created, but before the
> creation of any cpu. To to so, add an option on memstress_create_vm() that
> takes dirty-ring size, and enables it at the correct moment.
> 
> This required a new function memstress_vm_create_with_vcpus() to be
> created based on the previously used __vm_create_with_vcpus();

Rather than pile on more params, if I ask really nicely, would you rework
memstress_create_vm() and friends APIs to take a "struct memstress_params"?
Except for dirty_log_page_splitting_test.c, all of the memstress tests already
use a struct, i.e. while tedious, it should be straightforward and won't put
undue burden on tests (which is why the core VM creation APIs don't take a struct
of params).

Then it will be easier to extend memstress in the future, and I suspect the
existing code will come out cleaner as well.  E.g. dirty_log_perf_test.c stores
nr_vcpus as a global, despite it being fully contained by main() => run_test(),
right alongside the test params...