Re: [RFC] /dev/ioasid uAPI proposal

From: Jason Wang
Date: Wed Jun 09 2021 - 22:02:27 EST

在 2021/6/8 下午9:20, Jason Gunthorpe 写道:
On Tue, Jun 08, 2021 at 09:10:42AM +0800, Jason Wang wrote:

Well, this sounds like a re-invention of io_uring which has already worked
for multifds.
How so? io_uring is about sending work to the kernel, not getting
structued events back?

Actually it can. Userspace can poll multiple fds via preparing multiple sqes with IORING_OP_ADD flag.

It is more like one of the perf rings

This means another ring and we need introduce ioctl() to add or remove ioasids from the poll. And it still need a kind of fallback like a list if the ring is full.