intel-iommu: Speed up processing of the identity_mapping function
authorMike Travis <travis@sgi.com>
Sat, 28 May 2011 18:15:03 +0000 (13:15 -0500)
committerDavid Woodhouse <David.Woodhouse@intel.com>
Wed, 1 Jun 2011 11:47:36 +0000 (12:47 +0100)
commitcb452a4040bb051d92e85d6e7eb60c11734c1781
treeef19298ec70274c9c199fa74a4f08e77cc69080b
parent8fcc5372fbac085199d84a880503ed67aba3fe49
intel-iommu: Speed up processing of the identity_mapping function

When there are a large count of PCI devices, and the pass through
option for iommu is set, much time is spent in the identity_mapping
function hunting though the iommu domains to check if a specific
device is "identity mapped".

Speed up the function by checking the cached info to see if
it's mapped to the static identity domain.

Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Mike Habeck <habeck@sgi.com>
Cc: stable@kernel.org
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
drivers/pci/intel-iommu.c