Re: [PATCH 2/2] fix compilation with kvm disabled

["Michael S. Tsirkin" <mst@redhat.com>]

On Tue, Jul 07, 2009 at 02:36:31PM -0400, Glauber Costa wrote:
> Signed-off-by: Glauber Costa <glommer@redhat.com>
> ---
>  hw/msix.c |   14 ++++++++++++++
>  1 files changed, 14 insertions(+), 0 deletions(-)
> 
> diff --git a/hw/msix.c b/hw/msix.c
> index b6f3948..8636f69 100644
> --- a/hw/msix.c
> +++ b/hw/msix.c
> @@ -63,6 +63,7 @@
>  /* Flag for interrupt controller to declare MSI-X support */
>  int msix_supported;
>  
> +#ifdef USE_KVM
>  /* KVM specific MSIX helpers */
>  static void kvm_msix_free(PCIDevice *dev)
>  {
> @@ -157,6 +158,14 @@ static void kvm_msix_del(PCIDevice *dev, unsigned vector)
>      kvm_del_routing_entry(kvm_context, &dev->msix_irq_entries[vector]);
>      kvm_commit_irq_routes(kvm_context);
>  }
> +#else
> +
> +static void kvm_msix_free(PCIDevice *dev) {}
> +static void kvm_msix_update(PCIDevice *dev, int vector,
> +                            int was_masked, int is_masked) {}
> +static int kvm_msix_add(PCIDevice *dev, unsigned vector) { return -1; }
> +static void kvm_msix_del(PCIDevice *dev, unsigned vector) {}
> +#endif
>  
>  /* Add MSI-X capability to the config space for the device. */
>  /* Given a bar and its size, add MSI-X table on top of it

Thanks for fix!

> @@ -337,10 +346,12 @@ int msix_init(struct PCIDevice *dev, unsigned short nentries,
>      if (nentries > MSIX_MAX_ENTRIES)
>          return -EINVAL;
>  
> +#ifdef KVM_CAP_IRQCHIP
>      if (kvm_enabled() && qemu_kvm_irqchip_in_kernel()) {
>          dev->msix_irq_entries = qemu_malloc(nentries *
>                                              sizeof *dev->msix_irq_entries);
>      }
> +#endif
>      dev->msix_entry_used = qemu_mallocz(MSIX_MAX_ENTRIES *
>                                          sizeof *dev->msix_entry_used);
>  
> @@ -454,10 +465,13 @@ void msix_notify(PCIDevice *dev, unsigned vector)
>          msix_set_pending(dev, vector);
>          return;
>      }
> +
> +#ifdef KVM_CAP_IRQCHIP
>      if (kvm_enabled() && qemu_kvm_irqchip_in_kernel()) {
>          kvm_set_irq(dev->msix_irq_entries[vector].gsi, 1, NULL);
>          return;
>      }
> +#endif
>  
>      address = pci_get_long(table_entry + MSIX_MSG_UPPER_ADDR);
>      address = (address << 32) | pci_get_long(table_entry + MSIX_MSG_ADDR);

I think it's time we stopped worrying about builds against old kernel
headers or without them. What do we gain from it?

I believe that the right thing to do is to define kvm_enabled as a macro
returning 0, and let compiler optimize the code out.

Avi?

-- 
MST