Re: Questions about IORING_OP_ASYNC_CANCEL usage

Carter Li 李通洲
2020-08-21T05:21:03Z

Sorry, please ignore this mail, I’ll send a new one

> 2020年8月21日 下午1:17，Carter Li 李通洲 <carter.li@eoitek.com> 写道：
>
> Hi Jens,
>
> I have some ( maybe stupid ) questions about IORING_OP_ASYNC_CANCEL:
>
> 1. Does IORING_OP_ASYNC_CANCEL always complete inline ( i.e. finishes before the io_uring_enter syscall returns )?
>
> 2. Does recent changes of async buffered reads have any impact with cancelation? Can we cancel a buffered IORING_OP_READV operation after it’s started? Although the disk->kernel DMA operation is not cancelable, can we cancel the kernel->userland data copy?
>
> 3. I heard that all buffered writes are serialized on the inode mutex. If a buffered IORING_OP_WRITEV is blocked on the node mutex, can we cancel it?
>
> Thanks in advance,
> Carter