[PATCH] io_uring: remove unneeded io_send_zc accounting

[PATCH] io_uring: remove unneeded io_send_zc accounting

[Dylan Yudaken]

zc->len and zc->buf are not actually used once you get to the retry
stage. The buffer remains in kmsg->msg.msg_iter, which is setup in
io_send_setup.
Note: it still seems needed in io_send due to io_send_select_buffer
needing it (for the len parameter).

Signed-off-by: Dylan Yudaken <dyudaken@gmail.com>
---
Hi,

I'm reasonably sure this is correct - but I think Pavel might want to
double check that I did not miss anything. The tests seem to pass with no
changes.

Thanks,
Dylan


 io_uring/net.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/io_uring/net.c b/io_uring/net.c
index a6f3cbb7dfea..8576c6cb2236 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -1493,8 +1493,6 @@ int io_send_zc(struct io_kiocb *req, unsigned int issue_flags)
 			return -EAGAIN;
 
 		if (ret > 0 && io_net_retry(sock, kmsg->msg.msg_flags)) {
-			zc->len -= ret;
-			zc->buf += ret;
 			zc->done_io += ret;
 			return -EAGAIN;
 		}

base-commit: 26a4cfaff82a2dcb810f6bfd5f4842f9b6046c8a
-- 
2.50.1

Re: [PATCH] io_uring: remove unneeded io_send_zc accounting

[Pavel Begunkov]

On 2/15/26 23:15, Dylan Yudaken wrote:
> zc->len and zc->buf are not actually used once you get to the retry
> stage. The buffer remains in kmsg->msg.msg_iter, which is setup in
> io_send_setup.
> Note: it still seems needed in io_send due to io_send_select_buffer
> needing it (for the len parameter).
> 
> Signed-off-by: Dylan Yudaken <dyudaken@gmail.com>
> ---
> Hi,
> 
> I'm reasonably sure this is correct - but I think Pavel might want to
> double check that I did not miss anything. The tests seem to pass with no
> changes.

Looks good, I'll have a look tomorrow

-- 
Pavel Begunkov

Re: [PATCH] io_uring: remove unneeded io_send_zc accounting

[Pavel Begunkov]

On 2/15/26 23:39, Pavel Begunkov wrote:
> On 2/15/26 23:15, Dylan Yudaken wrote:
>> zc->len and zc->buf are not actually used once you get to the retry
>> stage. The buffer remains in kmsg->msg.msg_iter, which is setup in
>> io_send_setup.
>> Note: it still seems needed in io_send due to io_send_select_buffer
>> needing it (for the len parameter).
>>
>> Signed-off-by: Dylan Yudaken <dyudaken@gmail.com>
>> ---
>> Hi,
>>
>> I'm reasonably sure this is correct - but I think Pavel might want to
>> double check that I did not miss anything. The tests seem to pass with no
>> changes.
> 
> Looks good, I'll have a look tomorrow

Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>

I like the change, and we should get rid of duplication between
send and sendmsg on top.

-- 
Pavel Begunkov

Re: [PATCH] io_uring: remove unneeded io_send_zc accounting

[Jens Axboe]

On 2/15/26 4:15 PM, Dylan Yudaken wrote:
> zc->len and zc->buf are not actually used once you get to the retry
> stage. The buffer remains in kmsg->msg.msg_iter, which is setup in
> io_send_setup.
> Note: it still seems needed in io_send due to io_send_select_buffer
> needing it (for the len parameter).
> 
> Signed-off-by: Dylan Yudaken <dyudaken@gmail.com>
> ---
> Hi,
> 
> I'm reasonably sure this is correct - but I think Pavel might want to
> double check that I did not miss anything. The tests seem to pass with no
> changes.

FWIW looks good to me, and we should probably move towards just
tracking state in iov_iter for the other paths too and get rid of
this. Wild handwaving, haven't actually looked at it, but it'd be
a nice cleanup.

-- 
Jens Axboe

Re: [PATCH] io_uring: remove unneeded io_send_zc accounting

[Jens Axboe]

On Sun, 15 Feb 2026 23:15:23 +0000, Dylan Yudaken wrote:
> zc->len and zc->buf are not actually used once you get to the retry
> stage. The buffer remains in kmsg->msg.msg_iter, which is setup in
> io_send_setup.
> Note: it still seems needed in io_send due to io_send_select_buffer
> needing it (for the len parameter).
> 
> 
> [...]

Applied, thanks!

[1/1] io_uring: remove unneeded io_send_zc accounting
      commit: 046fcc83ac1ba8747f0bcae13f5e433802735245

Best regards,
-- 
Jens Axboe