Hi folks, This series tries to optimize the uses of two locks in the Intel IOMMU driver:
- The intel_iommu::lock is used to protect the IOMMU resources shared by devices. They include the IOMMU root and context tables, the pasid tables and the domain IDs. - The global device_domain_lock is used to protect the global and the per-domain device tracking lists. The optimization includes: - Remove the unnecessary global device tracking list; - Remove unnecessary locking; - Reduce the scope of the lock as much as possible, that is, use the lock only where necessary; - The global lock is transformed into a local lock to improve the efficiency. This series is also available on github: https://github.com/LuBaolu/intel-iommu/commits/intel-iommu-lock-optimization-v4 Your comments and suggestions are very appreciated. Best regards, baolu Change log: v4: - Kevin pointed out that the copy table failure path needs some improvements. We agreed that it worth a separated series to handle all improvements on copy table. - Kevin suggested that we could put all spinlock replacement changes in a single patch. Updated in this series. - Others look good to Kevin. (Thanks and very appreciated for all the review comments.) v3: - https://lore.kernel.org/linux-iommu/20220629074725.2331441-1-baolu...@linux.intel.com/ - Split reduction of lock ranges from changing irqsave. https://lore.kernel.org/linux-iommu/bn9pr11mb52760a3d7c6bf1af9c9d34658c...@bn9pr11mb5276.namprd11.prod.outlook.com/ - Fully initialize the dev_info before adding it to the list. https://lore.kernel.org/linux-iommu/bn9pr11mb52764d7cd86448c5e4eb46668c...@bn9pr11mb5276.namprd11.prod.outlook.com/ - Various code and comments refinement. v2: - https://lore.kernel.org/linux-iommu/20220614025137.1632762-1-baolu...@linux.intel.com/ - Split the lock-free page walk issue into a new patch: https://lore.kernel.org/linux-iommu/20220609070811.902868-1-baolu...@linux.intel.com/ - Drop the conversion from spinlock to mutex and make this series cleanup purpose only. - Address several comments received during v1 review. v1: - https://lore.kernel.org/linux-iommu/20220527063019.3112905-1-baolu...@linux.intel.com/ - Initial post. Lu Baolu (11): iommu/vt-d: debugfs: Remove device_domain_lock usage iommu/vt-d: Remove clearing translation data in disable_dmar_iommu() iommu/vt-d: Use pci_get_domain_bus_and_slot() in pgtable_walk() iommu/vt-d: Unnecessary spinlock for root table alloc and free iommu/vt-d: Replace spin_lock_irqsave() with spin_lock() iommu/vt-d: Acquiring lock in domain ID allocation helpers iommu/vt-d: Acquiring lock in pasid manipulation helpers iommu/vt-d: Check device list of domain in domain free path iommu/vt-d: Fold __dmar_remove_one_dev_info() into its caller iommu/vt-d: Use device_domain_lock accurately iommu/vt-d: Convert global spinlock into per domain lock drivers/iommu/intel/iommu.h | 3 +- drivers/iommu/intel/pasid.h | 1 + drivers/iommu/intel/debugfs.c | 49 ++++--- drivers/iommu/intel/iommu.c | 249 ++++++++++------------------------ drivers/iommu/intel/pasid.c | 103 +++++++------- drivers/iommu/intel/svm.c | 5 +- 6 files changed, 163 insertions(+), 247 deletions(-) -- 2.25.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
