This series intends to implement IRQ offloading for vhost_vdpa. By the feat of irq forwarding facilities like posted interrupt on X86, irq bypass can help deliver interrupts to vCPU directly. vDPA devices have dedicated hardware backends like VFIO pass-throughed devices. So it would be possible to setup irq offloading(irq bypass) for vDPA devices and gain performance improvements. In my testing, with this feature, we can save 0.1ms in a ping between two VFs on average. changes from V1: (1)dropped vfio changes. (3)removed KVM_HVAE_IRQ_BYPASS checks (4)locking fixes (5)simplified vhost_vdpa_update_vq_irq() (6)minor improvements Zhu Lingshan (6): vhost: introduce vhost_call_ctx kvm: detect assigned device via irqbypass manager vDPA: implement IRQ offloading helpers in vDPA core vhost_vdpa: implement IRQ offloading in vhost_vdpa ifcvf: replace irq_request/free with vDPA helpers irqbypass: do not start cons/prod when failed connect arch/x86/kvm/x86.c | 10 ++++++-- drivers/vdpa/ifcvf/ifcvf_main.c | 14 +++++++---- drivers/vdpa/vdpa.c | 42 +++++++++++++++++++++++++++++++++ drivers/vhost/Kconfig | 1 + drivers/vhost/vdpa.c | 52 +++++++++++++++++++++++++++++++++++++++-- drivers/vhost/vhost.c | 22 ++++++++++++----- drivers/vhost/vhost.h | 9 ++++++- include/linux/vdpa.h | 13 +++++++++++ virt/lib/irqbypass.c | 16 ++++++++----- 9 files changed, 157 insertions(+), 22 deletions(-) -- 1.8.3.1
