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| author | Lu Baolu <baolu.lu@linux.intel.com> | 2024-02-27 10:14:40 +0800 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2024-03-01 13:51:20 +0100 |
| commit | 1a75cc710b956010137b4fe1d1fa3282bfd8f86c (patch) | |
| tree | fa3b9190580b53d6050052170521ce414e28fd45 /drivers/iommu/intel/dmar.c | |
| parent | 8ca918cbc2522e72faa5c102d02059e53d5128d0 (diff) | |
| download | linux-1a75cc710b956010137b4fe1d1fa3282bfd8f86c.tar.gz linux-1a75cc710b956010137b4fe1d1fa3282bfd8f86c.tar.bz2 linux-1a75cc710b956010137b4fe1d1fa3282bfd8f86c.zip | |
iommu/vt-d: Use rbtree to track iommu probed devices
Use a red-black tree(rbtree) to track devices probed by the driver's
probe_device callback. These devices need to be looked up quickly by
a source ID when the hardware reports a fault, either recoverable or
unrecoverable.
Fault reporting paths are critical. Searching a list in this scenario
is inefficient, with an algorithm complexity of O(n). An rbtree is a
self-balancing binary search tree, offering an average search time
complexity of O(log(n)). This significant performance improvement
makes rbtrees a better choice.
Furthermore, rbtrees are implemented on a per-iommu basis, eliminating
the need for global searches and further enhancing efficiency in
critical fault paths. The rbtree is protected by a spin lock with
interrupts disabled to ensure thread-safe access even within interrupt
contexts.
Co-developed-by: Huang Jiaqing <jiaqing.huang@intel.com>
Signed-off-by: Huang Jiaqing <jiaqing.huang@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20240220065939.121116-2-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu/intel/dmar.c')
| -rw-r--r-- | drivers/iommu/intel/dmar.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c index 23cb80d62a9a..f9b63c2875f7 100644 --- a/drivers/iommu/intel/dmar.c +++ b/drivers/iommu/intel/dmar.c @@ -1095,7 +1095,8 @@ static int alloc_iommu(struct dmar_drhd_unit *drhd) iommu->agaw = agaw; iommu->msagaw = msagaw; iommu->segment = drhd->segment; - + iommu->device_rbtree = RB_ROOT; + spin_lock_init(&iommu->device_rbtree_lock); iommu->node = NUMA_NO_NODE; ver = readl(iommu->reg + DMAR_VER_REG); |