Revamping ioctl with io_uring - Kanchan Joshi & Anuj Gupta, Samsung Semiconductor India Research

Revamping ioctl with io_uring - Kanchan Joshi & Anuj Gupta, Samsung Semiconductor India Research

There is usually a need to communicate between user-space and kernel in a way that has not been imagined before. Coining a brand-new generic system call has been hard and actively discouraged. Therefore, ioctl, the multiplexor system call, gained popularity and accumulated massive adoption. However, ioctl has been anything but efficient. Particularly for high-performance asynchronous software, this leaves a lot to be desired. This talk describes a new facility, io_uring command that aims to address this gap. As a modern equivalent of asynchronous ioctl, it made its way into the 5.19 kernel and got more resourceful with further releases. We elaborate on how a Linux developer can use this infrastructure to attach various io_uring capabilities with any arbitrary command. Specifically, the session will cover the following: • API and design of io_uring command • Present examples of using this interface on a fast storage device (i.e., NVMe SSD) • How to use various efficiency knobs of io_uring The audience will walk away with a better understanding of io_uring and how to build efficient pathways between kernel and user space.

Видео Revamping ioctl with io_uring - Kanchan Joshi & Anuj Gupta, Samsung Semiconductor India Research канала The Linux Foundation