On Thu, Jun 09, 2022 at 02:19:06PM +0100, Robin Murphy wrote: > Is there a significant benefit to keeping both paths, or could we get away > with just always using RCU? Realistically, pagetable pages aren't likely to > be freed all that frequently, except perhaps at domain teardown, but that > shouldn't really be performance-critical, and I guess we could stick an RCU > sync point in iommu_domain_free() if we're really worried about releasing > larger quantities of pages back to the allocator ASAP?
I think you are right, anything that uses the iommu_iotlb_gather may as well use RCU too. IIRC the allocators already know that RCU is often sitting on freed-memory and have some contigency to flush it out before OOMing, so nothing special should be needed. Jason _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
