[PATCHSET,for-next,0/3] Fix read/write -EAGAIN failure cases

Message

Jens Axboe Jan. 9, 2025, 6:15 p.m. UTC

Hi,

After I had originally ensured that all read/write requests were
fully retryable (with the 6.10 "always allocate async data" changes),
there was an attempt or two at getting rid of these -EAGAIN's bubbling
back to userspace. See:

commit 039a2e800bcd5beb89909d1a488abf3d647642cf
Author: Jens Axboe <[e-mail]>
Date:   Thu Apr 25 09:04:32 2024 -0600

    io_uring/rw: reinstate thread check for retries

and the other two commits it references.

Here's another attempt, which simply moves this kind of checking to
be at completion time. This solves the issue of REQ_F_REISSUE being
missed in case it gets sets outside of submission context, and
generally just cleans up the random REQ_F_REISSUE checking that
otherwise needs to happen for the read/write issue path.

Patch 1 is just a cleanup, patch 2 does the actual change, and patch 3
finally removes the thread group checking in the "Can I resubmit"
checks.

 io_uring/io_uring.c | 15 +++++++-
 io_uring/rw.c       | 89 ++++++++++++++-------------------------------
 2 files changed, 40 insertions(+), 64 deletions(-)