Re: [PATCH 01/10] KVM: selftests: Take vcpu pointer instead of id in vm_vcpu_rm()

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




On 4/14/20 5:25 AM, Andrew Jones wrote:
On Mon, Apr 13, 2020 at 02:26:59PM -0700, Sean Christopherson wrote:
On Mon, Apr 13, 2020 at 03:26:55PM -0300, Wainer dos Santos Moschetta wrote:
On 4/10/20 8:16 PM, Sean Christopherson wrote:
The sole caller of vm_vcpu_rm() already has the vcpu pointer, take it
directly instead of doing an extra lookup.

Most of (if not all) vcpu related functions in kvm_util.c receives an id, so
this change creates an inconsistency.
Ya, but taking the id is done out of "necessity", as everything is public
and for whatever reason the design of the selftest framework is to not
expose 'struct vcpu' outside of the utils.  vm_vcpu_rm() is internal only,
IMO pulling the id out of the vcpu just to lookup the same vcpu is a waste
of time.
Agreed


Thanks Sean and Andrew for your comments. I'm not in position to change/propose any design of kvm selftests but even though I aimed to foster this discussion.

So, please, consider my Reviewed-by...

- Wainer



FWIW, I think the whole vcpuid thing is a bad interface, almost all the
tests end up defining an arbitrary number for the sole VCPU_ID, i.e. the
vcpuid interface just adds a pointless layer of obfuscation.  I haven't
looked through all the tests, but returning the vcpu and making the struct
opaque, same as kvm_vm, seems like it would yield more readable code with
less overhead.
Agreed

While I'm on a soapbox, hiding 'struct vcpu' and 'struct kvm_vm' also seems
rather silly, but at least that doesn't directly lead to funky code.
Agreed. While the concept has been slowly growing on me, I think accessor
functions for each of the structs members are growing even faster...

Thanks,
drew

Disregarding the above comment, the changes look good to me. So:

Reviewed-by: Wainer dos Santos Moschetta <wainersm@xxxxxxxxxx>


Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
---
  tools/testing/selftests/kvm/lib/kvm_util.c | 7 +++----
  1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 8a3523d4434f..9a783c20dd26 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -393,7 +393,7 @@ struct vcpu *vcpu_find(struct kvm_vm *vm, uint32_t vcpuid)
   *
   * Input Args:
   *   vm - Virtual Machine
- *   vcpuid - VCPU ID
+ *   vcpu - VCPU to remove
   *
   * Output Args: None
   *
@@ -401,9 +401,8 @@ struct vcpu *vcpu_find(struct kvm_vm *vm, uint32_t vcpuid)
   *
   * Within the VM specified by vm, removes the VCPU given by vcpuid.
   */
-static void vm_vcpu_rm(struct kvm_vm *vm, uint32_t vcpuid)
+static void vm_vcpu_rm(struct kvm_vm *vm, struct vcpu *vcpu)
  {
-	struct vcpu *vcpu = vcpu_find(vm, vcpuid);
  	int ret;
  	ret = munmap(vcpu->state, sizeof(*vcpu->state));
@@ -427,7 +426,7 @@ void kvm_vm_release(struct kvm_vm *vmp)
  	int ret;
  	while (vmp->vcpu_head)
-		vm_vcpu_rm(vmp, vmp->vcpu_head->id);
+		vm_vcpu_rm(vmp, vmp->vcpu_head);
  	ret = close(vmp->fd);
  	TEST_ASSERT(ret == 0, "Close of vm fd failed,\n"




[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]

  Powered by Linux