linux/include
Jason Gunthorpe 5448c1558f iommupt: Add the Intel VT-d second stage page table format
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>
2025-11-05 09:50:17 +01:00
..
acpi More power management updates for 6.18-rc1 2025-10-07 09:39:51 -07:00
asm-generic hyperv-next for v6.18 2025-10-07 08:40:15 -07:00
clocksource
crypto This update includes the following changes: 2025-10-04 14:59:29 -07:00
cxl
drm drm/gpuvm: Fix kernel-doc warning for drm_gpuvm_map_req.map 2025-10-15 18:37:05 +02:00
dt-bindings There's a bunch of patches here across drivers/clk/ to migrate drivers to use 2025-10-07 09:28:37 -07:00
hyperv hyperv: Remove the spurious null directive line 2025-10-02 21:21:24 +00:00
keys
kunit linux_kselftest-kunit-6.18-rc1 2025-10-01 19:15:11 -07:00
kvm KVM: arm64: Kill leftovers of ad-hoc timer userspace access 2025-10-13 14:42:41 +01:00
linux iommupt: Add the Intel VT-d second stage page table format 2025-11-05 09:50:17 +01:00
math-emu
media
memory
misc
net net/ip6_tunnel: Prevent perpetual tunnel growth 2025-10-13 17:43:46 -07:00
pcmcia
ras
rdma
rv kernel-6.18-rc1.clone3 2025-09-29 10:36:50 -07:00
scsi SCSI misc on 20251002 2025-10-03 19:17:48 -07:00
soc There's a bunch of patches here across drivers/clk/ to migrate drivers to use 2025-10-07 09:28:37 -07:00
sound ASoC: tas2781: Support more newly-released amplifiers tas58xx in the driver 2025-10-13 11:08:09 +01:00
target
trace dma-mapping fixes for Linux 6.18: 2025-10-07 12:48:06 -07:00
uapi drm/xe/uapi: Hide the madvise autoreset behind a VM_BIND flag 2025-10-20 17:03:44 -07:00
ufs scsi: ufs: core: Include UTP error in INT_FATAL_ERRORS 2025-09-30 16:10:29 -04:00
vdso Updates for the VDSO subsystem: 2025-09-30 16:58:21 -07:00
video
xen
Kbuild