| Message ID | 20220819121946.676065-1-dylany@fb.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | io_uring: defer task work to when it is needed | expand |
On 8/19/22 20:19, Dylan Yudaken wrote: > We have seen workloads which suffer due to the way task work is currently > scheduled. This scheduling can cause non-trivial tasks to run interrupting > useful work on the workload. For example in network servers, a large async > recv may run, calling memcpy on a large packet, interrupting a send. Which > would add latency. > > This series adds an option to defer async work until user space calls > io_uring_enter with the GETEVENTS flag. This allows the workload to choose > when to schedule async work and have finer control (at the expense of > complexity of managing this) of scheduling. > > Patches 1,2 are prep patches > Patch 3 changes io_uring_enter to not pre-run task work > Patch 4/5/6 adds the new flag and functionality > Patch 7 adds tracing for the local task work running > > Changes since v2: > - add a patch to trace local task work run > - return -EEXIST if calling from the wrong task > - properly handle shutting down due to an exec > - remove 'all' parameter from io_run_task_work_ctx > > Changes since v1: > - Removed the first patch (using ctx variable) which was broken > - Require IORING_SETUP_SINGLE_ISSUER and make sure waiter task > is the same as the submitter task > - Just don't run task work at the start of io_uring_enter (Pavel's > suggestion) > - Remove io_move_task_work_from_local > - Fix locking bugs > > Dylan Yudaken (7): > io_uring: remove unnecessary variable > io_uring: introduce io_has_work > io_uring: do not run task work at the start of io_uring_enter > io_uring: add IORING_SETUP_DEFER_TASKRUN > io_uring: move io_eventfd_put > io_uring: signal registered eventfd to process deferred task work > io_uring: trace local task work run > > include/linux/io_uring_types.h | 3 + > include/trace/events/io_uring.h | 29 ++++ > include/uapi/linux/io_uring.h | 7 + > io_uring/cancel.c | 2 +- > io_uring/io_uring.c | 264 ++++++++++++++++++++++++++------ > io_uring/io_uring.h | 29 +++- > io_uring/rsrc.c | 2 +- > 7 files changed, 285 insertions(+), 51 deletions(-) > > > base-commit: 5993000dc6b31b927403cee65fbc5f9f070fa3e4 > prerequisite-patch-id: cb1d024945aa728d09a131156140a33d30bc268b Apart from the comments, others looks good to me, Acked-by: Hao Xu <howeyxu@tencent.com>