Registering the single issuer task from the first submit adds unnecesary complications to the API as well as the implementation. Where simply registering it at creation should not impose any barriers to getting the same performance wins. The only catch is users that might want to move the ring after creation but before submission. For these users allow them to create the ring with IORING_SETUP_R_DISABLED and then enable it on the submission task. There is another problem in 6.1, with IORING_SETUP_DEFER_TASKRUN. That would like to check the submitter_task from unlocked contexts, which would be racy. If upfront the submitter_task is set at creation time it will simplify the logic there and probably increase performance (though this is unmeasured). Patch 1 registers the task at creation of the io_uring, this works standalone in case you want to only merge this part for 6.0 Patch 2/3 cleans up the code from the old style v2: - add the IORING_SETUP_R_DISABLED logic Dylan Yudaken (3): io_uring: register single issuer task at creation io_uring: simplify __io_uring_add_tctx_node io_uring: remove io_register_submitter io_uring/io_uring.c | 9 ++++++++- io_uring/tctx.c | 42 ++++++++++++++++++------------------------ io_uring/tctx.h | 6 ++++-- 3 files changed, 30 insertions(+), 27 deletions(-) base-commit: f76349cf41451c5c42a99f18a9163377e4b364ff -- 2.30.2
