commit: cb452a4040bb051d92e85d6e7eb60c11734c1781 From: Mike Travis <[email protected]> Date: Sat, 28 May 2011 13:15:03 -0500 Subject: [PATCH] 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 <[email protected]> Reviewed-by: Mike Habeck <[email protected]> Cc: [email protected] Signed-off-by: David Woodhouse <[email protected]> --- drivers/pci/intel-iommu.c | 6 +++--- 1 files changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c index dcf051d..98be0b5 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; } _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
