[openib-general] Default of MSI on when MSI support is configured into the kernel

[Woodruff, Robert J]

Hi Roland,

I just loaded the patch-linux-2.6.11-rc2 to load on my small cluster for
testing.  

One question, I found that I have to modify things to turn on using MSI.

Is there any reason that we cannot just change the mtcha driver to use
MSI by default when CONFIG_PCI_MSI is configured in the kernel ?
People that don't support or want to use MSI can always disable it when
the build 
their kernel, or override the values when they do the modprobe. 

i.e., 

In mthca_main.c 

#ifdef CONFIG_PCI_MSI

static int msi_x = 1;
module_param(msi_x, int, 0444);
MODULE_PARM_DESC(msi_x, "attempt to use MSI-X if nonzero");

static int msi = 1;
module_param(msi, int, 0444);
MODULE_PARM_DESC(msi, "attempt to use MSI if nonzero");

#else /* CONFIG_PCI_MSI */

#define msi_x (0)
#define msi   (0)

#endif /* CONFIG_PCI_MSI */