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5448c1558f
The VT-d second stage format is almost the same as the x86 PAE format,
except the bit encodings in the PTE are different and a few new PTE
features, like force coherency are present.
Among all the formats it is unique in not having a designated present bit.
Comparing the performance of several operations to the existing version:
iommu_map()
pgsz ,avg new,old ns, min new,old ns , min % (+ve is better)
2^12, 53,66 , 50,64 , 21.21
2^21, 59,70 , 56,67 , 16.16
2^30, 54,66 , 52,63 , 17.17
256*2^12, 384,524 , 337,516 , 34.34
256*2^21, 387,632 , 336,626 , 46.46
256*2^30, 376,629 , 323,623 , 48.48
iommu_unmap()
pgsz ,avg new,old ns, min new,old ns , min % (+ve is better)
2^12, 67,86 , 63,84 , 25.25
2^21, 64,84 , 59,80 , 26.26
2^30, 59,78 , 56,74 , 24.24
256*2^12, 216,335 , 198,317 , 37.37
256*2^21, 245,350 , 232,344 , 32.32
256*2^30, 248,345 , 226,339 , 33.33
Cc: Tina Zhang <tina.zhang@intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>