[PATCH v4 00/11] fixed worker

[Hao Xu <haoxu.linux@icloud.com>]

From: Hao Xu <howeyxu@tencent.com>

This is the second version of fixed worker implementation.
Wrote a nop test program to test it, 3 fixed-workers VS 3 normal workers.
normal workers:
./run_nop_wqe.sh nop_wqe_normal 200000 100 3 1-3
        time spent: 10464397 usecs      IOPS: 1911242
        time spent: 9610976 usecs       IOPS: 2080954
        time spent: 9807361 usecs       IOPS: 2039284

fixed workers:
./run_nop_wqe.sh nop_wqe_fixed 200000 100 3 1-3
        time spent: 17314274 usecs      IOPS: 1155116
        time spent: 17016942 usecs      IOPS: 1175299
        time spent: 17908684 usecs      IOPS: 1116776

About 2x improvement. From perf result, almost no acct->lock contension.
Test program: https://github.com/HowHsu/liburing/tree/fixed_worker
liburing/test/nop_wqe.c

v3->v4:
 - make work in fixed worker's private worfixed worker
 - tweak the io_wqe_acct struct to make it clearer


Hao Xu (11):
  io-wq: add a worker flag for individual exit
  io-wq: change argument of create_io_worker() for convienence
  io-wq: add infra data structure for fixed workers
  io-wq: tweak io_get_acct()
  io-wq: fixed worker initialization
  io-wq: fixed worker exit
  io-wq: implement fixed worker logic
  io-wq: batch the handling of fixed worker private works
  io_uring: add register fixed worker interface
  io-wq: add an work list for fixed worker
  io_uring: cancel works in exec work list for fixed worker

 fs/io-wq.c                    | 481 ++++++++++++++++++++++++++++++----
 fs/io-wq.h                    |   8 +
 fs/io_uring.c                 |  71 +++++
 include/uapi/linux/io_uring.h |  11 +
 4 files changed, 525 insertions(+), 46 deletions(-)


base-commit: fa5da31df51f8f581ec1776e613c1bcabbe9559f
-- 
2.25.1