On Fri, 2022-07-08 at 11:43 -0700, Dylan Yudaken wrote: > This series adds multishot support to recvmsg in io_uring. > > The idea is that you submit a single multishot recvmsg and then receive > completions as and when data arrives. For recvmsg each completion also has > control data, and this is necessarily included in the same buffer as the > payload. > > In order to do this a new structure is used: io_uring_recvmsg_out. This > specifies the length written of the name, control and payload. As well as > including the flags. > The layout of the buffer is <header><name><control><payload> where the > lengths are those specified in the original msghdr used to issue the recvmsg. > > I suspect this API will be the most contentious part of this series and would > appreciate any comments on it. > > For completeness I considered having the original struct msghdr as the header, > but size wise it is much bigger (72 bytes including an iovec vs 16 bytes here). > Testing also showed a 1% slowdown in terms of QPS. > > Using a mini network tester [1] shows 14% QPS improvment using this API, however > this is likely to go down to ~8% with the latest allocation cache added by Jens. > > I have based this on this other patch series [2]. > > [1]: https://github.com/DylanZA/netbench/tree/main > [2]: https://lore.kernel.org/io-uring/20220708181838.1495428-1-dylany@xxxxxx/ > > Dylan Yudaken (3): > net: copy from user before calling __copy_msghdr > net: copy from user before calling __get_compat_msghdr > io_uring: support multishot in recvmsg > > include/linux/socket.h | 7 +- > include/net/compat.h | 5 +- > include/uapi/linux/io_uring.h | 7 ++ > io_uring/net.c | 195 ++++++++++++++++++++++++++++------ > io_uring/net.h | 5 + > net/compat.c | 39 +++---- > net/socket.c | 37 +++---- > 7 files changed, 215 insertions(+), 80 deletions(-) > > > base-commit: 9802dee74e7f30ab52dc5f346373185cd860afab I read the above as this series is targeting Jens's tree. It looks like it should be conflicts-free vs net-next. For the network bits: Acked-by: Paolo Abeni <pabeni@xxxxxxxxxx> Cheers, Paolo
