From 0a4377de305684c883bf90ad21e3cbdeead70f5c Mon Sep 17 00:00:00 2001 From: Jiang Liu Date: Tue, 19 May 2015 17:07:14 +0800 Subject: [PATCH] genirq: Introduce irq_set_vcpu_affinity() to target an interrupt to a VCPU With Posted-Interrupts support in Intel CPU and IOMMU, an external interrupt from assigned-devices could be directly delivered to a virtual CPU in a virtual machine. Instead of hacking KVM and Intel IOMMU drivers, we propose a platform independent interface to target an interrupt to a specific virtual CPU in a virtual machine, or set virtual CPU affinity for an interrupt. By adopting this new interface and the hierarchy irqdomain, we could easily support posted-interrupts on Intel platforms, and also provide flexible enough interfaces for other platforms to support similar features. Here is the usage scenario for this interface: Guest update MSI/MSI-X interrupt configuration -->QEMU and KVM handle this -->KVM call this interface (passing posted interrupts descriptor and guest vector) -->irq core will transfer the control to IOMMU -->IOMMU will do the real work of updating IRTE (IRTE has new format for VT-d Posted-Interrupts) Signed-off-by: Jiang Liu Signed-off-by: Feng Wu Link: http://lkml.kernel.org/r/1432026437-16560-2-git-send-email-feng.wu@intel.com Signed-off-by: Thomas Gleixner --- Reading git-format-patch failed