On Wed, Jun 20, 2012 at 04:38:30PM -0500, Anthony Liguori wrote: > On 06/20/2012 04:32 PM, Michael S. Tsirkin wrote: > >On Wed, Jun 20, 2012 at 04:16:47PM -0500, Anthony Liguori wrote: > >>>diff --git a/hw/pci.h b/hw/pci.h > >>>index 7f223c0..ee669d9 100644 > >>>--- a/hw/pci.h > >>>+++ b/hw/pci.h > >>>@@ -558,10 +558,16 @@ static inline uint32_t pci_config_size(const > >>>PCIDevice *d) > >>> } > >>> > >>> /* DMA access functions */ > >>>+static inline DMAContext *pci_dma_context(PCIDevice *dev) > >>>+{ > >>>+ /* Stub for when we have no PCI iommu support */ > >>>+ return NULL; > >>>+} > >> > >>Why is all of this stuff static inline? > > > >Let's face it, most people don't need an MMU in their VM. > >inline stubs help make double sure we are not adding > >overhead for the sake of this niche case. > > It also makes for an overly complex pci.h with no obvious performance > justification. > A stub in a header plus an offline empty function is even more useless code. inline stubs is standard procedure.
> Let's not prematurely optimize here. > > Regards, > > Anthony Liguori It's not just an optimization. It is easier to see what's going on this way. -- MST