io-uring.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Carter Li 李通洲" <carter.li@eoitek.com>
To: Jens Axboe <axboe@kernel.dk>
Cc: io-uring <io-uring@vger.kernel.org>
Subject: Questions about IORING_OP_ASYNC_CANCEL usage
Date: Fri, 21 Aug 2020 05:22:42 +0000	[thread overview]
Message-ID: <49134331-96D8-45AE-83F2-E5409A6748E2@eoitek.com> (raw)

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

             reply	other threads:[~2020-08-21  5:22 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-08-21  5:22 Carter Li 李通洲 [this message]
  -- 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

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=49134331-96D8-45AE-83F2-E5409A6748E2@eoitek.com \
    --to=carter.li@eoitek.com \
    --cc=axboe@kernel.dk \
    --cc=io-uring@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).