path: root/drivers/pci/intel-iommu.c
diff options
authorMike Travis <travis@sgi.com>2011-05-28 13:15:03 -0500
committerDavid Woodhouse <David.Woodhouse@intel.com>2011-06-01 12:47:36 +0100
commitcb452a4040bb051d92e85d6e7eb60c11734c1781 (patch)
treeef19298ec70274c9c199fa74a4f08e77cc69080b /drivers/pci/intel-iommu.c
parent8fcc5372fbac085199d84a880503ed67aba3fe49 (diff)
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>
Diffstat (limited to 'drivers/pci/intel-iommu.c')
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index dcf051d53b74..98be0b55ac0b 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -2235,10 +2235,10 @@ static int identity_mapping(struct pci_dev *pdev)
if (likely(!iommu_identity_mapping))
return 0;
+ info = pdev->dev.archdata.iommu;
+ if (info && info != DUMMY_DEVICE_DOMAIN_INFO)
+ return (info->domain == si_domain);
- list_for_each_entry(info, &si_domain->devices, link)
- if (info->dev == pdev)
- return 1;
return 0;