[RFC 00/11] optimise registered buffer/file updates

Pavel Begunkov
2023-03-30T14:54:36Z

Updating registered files and buffers is a very slow operation, which
makes it not feasible for workloads with medium update frequencies.
Rework the underlying rsrc infra for greater performance and lesser
memory footprint.

The improvement is ~11x for a benchmark updating files in a loop
(1040K -> 11468K updates / sec).

The set requires a couple of patches from the 6.3 branch, for that
reason it's an RFC and will be resent after merge.

https://github.com/isilence/linux.git optimise-rsrc-update

Pavel Begunkov (11):
io_uring/rsrc: use non-pcpu refcounts for nodes
io_uring/rsrc: keep cached refs per node
io_uring: don't put nodes under spinlocks
io_uring: io_free_req() via tw
io_uring/rsrc: protect node refs with uring_lock
io_uring/rsrc: kill rsrc_ref_lock
io_uring/rsrc: rename rsrc_list
io_uring/rsrc: optimise io_rsrc_put allocation
io_uring/rsrc: don't offload node free
io_uring/rsrc: cache struct io_rsrc_node
io_uring/rsrc: add lockdep sanity checks

include/linux/io_uring_types.h | 7 +-
io_uring/io_uring.c | 47 ++++++----
io_uring/rsrc.c | 152 +++++++++++----------------------
io_uring/rsrc.h | 50 ++++++-----
4 files changed, 105 insertions(+), 151 deletions(-)

--
2.39.1