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* Questions about IORING_OP_ASYNC_CANCEL usage
@ 2020-08-21  5:22 Carter Li 李通洲
  0 siblings, 0 replies; 3+ messages in thread
From: Carter Li 李通洲 @ 2020-08-21  5:22 UTC (permalink / raw)
  To: Jens Axboe; +Cc: io-uring

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

^ permalink raw reply	[flat|nested] 3+ messages in thread
* Re: Questions about IORING_OP_ASYNC_CANCEL usage
  2020-08-21  5:17             ` Questions about IORING_OP_ASYNC_CANCEL usage Carter Li 李通洲
@ 2020-08-21  5:20               ` Carter Li 李通洲
  0 siblings, 0 replies; 3+ messages in thread
From: Carter Li 李通洲 @ 2020-08-21  5:20 UTC (permalink / raw)
  To: Jens Axboe; +Cc: io-uring

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


^ permalink raw reply	[flat|nested] 3+ messages in thread
* Questions about IORING_OP_ASYNC_CANCEL usage
  2020-02-25 21:13           ` Pavel Begunkov
@ 2020-08-21  5:17             ` Carter Li 李通洲
  2020-08-21  5:20               ` Carter Li 李通洲
  0 siblings, 1 reply; 3+ messages in thread
From: Carter Li 李通洲 @ 2020-08-21  5:17 UTC (permalink / raw)
  To: Jens Axboe; +Cc: io-uring

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

^ permalink raw reply	[flat|nested] 3+ messages in thread
end of thread, other threads:[~2020-08-21  5:22 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-08-21  5:22 Questions about IORING_OP_ASYNC_CANCEL usage Carter Li 李通洲
  -- strict thread matches above, loose matches on Subject: below --
2020-02-25  0:39 [RFC] single cqe per link Pavel Begunkov
2020-02-25  2:14 ` Carter Li 李通洲
2020-02-25  2:36   ` Jens Axboe
2020-02-25  3:13     ` Jens Axboe
2020-02-25 10:12       ` Pavel Begunkov
2020-02-25 20:20         ` Jens Axboe
2020-02-25 21:13           ` Pavel Begunkov
2020-08-21  5:17             ` Questions about IORING_OP_ASYNC_CANCEL usage Carter Li 李通洲
2020-08-21  5:20               ` Carter Li 李通洲

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