Hello Pavel, Jens and Guys, On Thu, Sep 12, 2024 at 06:49:20PM +0800, Ming Lei wrote: > Hello, > > The 1st 3 patches are cleanup, and prepare for adding sqe group. > > The 4th patch supports generic sqe group which is like link chain, but > allows each sqe in group to be issued in parallel and the group shares > same IO_LINK & IO_DRAIN boundary, so N:M dependency can be supported with > sqe group & io link together. sqe group changes nothing on > IOSQE_IO_LINK. > > The 5th patch supports one variant of sqe group: allow members to depend > on group leader, so that kernel resource lifetime can be aligned with > group leader or group, then any kernel resource can be shared in this > sqe group, and can be used in generic device zero copy. > > The 6th & 7th patches supports providing sqe group buffer via the sqe > group variant. > > The 8th patch supports ublk zero copy based on io_uring providing sqe > group buffer. > > Tests: > > 1) pass liburing test > - make runtests > > 2) write/pass sqe group test case and sqe provide buffer case: > > https://github.com/axboe/liburing/compare/master...ming1:liburing:sqe_group_v3 > > https://github.com/ming1/liburing/tree/sqe_group_v3 > > - covers related sqe flags combination and linking groups, both nop and > one multi-destination file copy. > > - cover failure handling test: fail leader IO or member IO in both single > group and linked groups, which is done in each sqe flags combination > test > > - covers IORING_PROVIDE_GROUP_KBUF by adding ublk-loop-zc > > 3) ublksrv zero copy: > > ublksrv userspace implements zero copy by sqe group & provide group > kbuf: > > git clone https://github.com/ublk-org/ublksrv.git -b group-provide-buf_v3 > make test T=loop/009:nbd/061 #ublk zc tests > > When running 64KB/512KB block size test on ublk-loop('ublk add -t loop --buffered_io -f $backing'), > it is observed that perf is doubled. > > > V6: > - follow Pavel's suggestion to disallow IOSQE_CQE_SKIP_SUCCESS & > LINK_TIMEOUT > - kill __io_complete_group_member() (Pavel) > - simplify link failure handling (Pavel) > - move members' queuing out of completion lock (Pavel) > - cleanup group io complete handler > - add more comment > - add ublk zc into liburing test for covering > IOSQE_SQE_GROUP & IORING_PROVIDE_GROUP_KBUF Any comments on V6? So that I may address them in next version since v6 has small conflict with mainline. thanks, Ming
