On Fri, Mar 10, 2023 at 4:50 PM Michael S. Tsirkin <mst@xxxxxxxxxx> wrote: > > On Tue, Feb 28, 2023 at 05:40:59PM +0800, Xie Yongji wrote: > > Hi all, > > > > This series introduces some ways to improve VDUSE performance. > > > Pls fix warnings reported by 0-day infra, dropping this for now. Note that I plan to review this next week. Thanks > > > > Patch 1 ~ 6 bring current interrupt affinity spreading mechanism > > to vduse device and make it possible for the virtio-blk driver > > to build the blk-mq queues based on it. This would be useful to > > mitigate the virtqueue lock contention in virtio-blk driver. In > > our test, with those patches, we could get ~50% improvement (600k > > iops -> 900k iops) when using per-cpu virtqueue. > > > > Patch 7 adds a sysfs interface for each vduse virtqueue to change > > the affinity for IRQ callback. It would be helpful for performance > > tuning when the affinity mask contains more than one CPU. > > > > Patch 8 ~ 9 associate an eventfd to the vdpa callback so that > > we can signal it directly during irq injection without scheduling > > an additional workqueue thread to do that. > > > > Patch 10, 11 add a sysfs interface to support specifying bounce > > buffer size in virtio-vdpa case. The high throughput workloads > > can benefit from it. And we can also use it to reduce the memory > > overhead for small throughput workloads. > > > > Please review, thanks! > > > > V2 to V3: > > - Rebased to newest kernel tree > > - Export group_cpus_evenly() instead of irq_create_affinity_masks() [MST] > > - Remove the sysfs for workqueue control [Jason] > > - Associate an eventfd to the vdpa callback [Jason] > > - Signal the eventfd directly in vhost-vdpa case [Jason] > > - Use round-robin to spread IRQs between CPUs in the affinity mask [Jason] > > - Handle the cpu hotplug case on IRQ injection [Jason] > > - Remove effective IRQ affinity and balance mechanism for IRQ allocation > > > > V1 to V2: > > - Export irq_create_affinity_masks() > > - Add set/get_vq_affinity and set_irq_affinity callbacks in vDPA > > framework > > - Add automatic irq callback affinity support in VDUSE driver [Jason] > > - Add more backgrounds information in commit log [Jason] > > - Only support changing effective affinity when the value is a subset > > of the IRQ callback affinity mask > > > > Xie Yongji (11): > > lib/group_cpus: Export group_cpus_evenly() > > vdpa: Add set/get_vq_affinity callbacks in vdpa_config_ops > > vdpa: Add set_irq_affinity callback in vdpa_config_ops > > vduse: Refactor allocation for vduse virtqueues > > vduse: Support automatic irq callback affinity > > vduse: Support set/get_vq_affinity callbacks > > vduse: Add sysfs interface for irq callback affinity > > vdpa: Add eventfd for the vdpa callback > > vduse: Signal interrupt's eventfd directly in vhost-vdpa case > > vduse: Delay iova domain creation > > vduse: Support specifying bounce buffer size via sysfs > > > > drivers/vdpa/vdpa_user/vduse_dev.c | 490 +++++++++++++++++++++++++---- > > drivers/vhost/vdpa.c | 2 + > > drivers/virtio/virtio_vdpa.c | 33 ++ > > include/linux/vdpa.h | 25 ++ > > lib/group_cpus.c | 1 + > > 5 files changed, 488 insertions(+), 63 deletions(-) > > > > -- > > 2.20.1 > _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
