Re: [PATCH v6] Use io_uring_register_ring_fd() to skip fd operations

[Sam Li <faithilikerun@gmail.com>]

Stefan Hajnoczi <stefanha@gmail.com> 于2022年5月31日周二 19:31写道：
>
> On Tue, May 31, 2022 at 06:50:11PM +0800, Sam Li wrote:
> > Linux recently added a new io_uring(7) optimization API that QEMU
> > doesn't take advantage of yet. The liburing library that QEMU uses
> > has added a corresponding new API calling io_uring_register_ring_fd().
> > When this API is called after creating the ring, the io_uring_submit()
> > library function passes a flag to the io_uring_enter(2) syscall
> > allowing it to skip the ring file descriptor fdget()/fdput()
> > operations. This saves some CPU cycles.
> >
> > Signed-off-by: Sam Li <faithilikerun@gmail.com>
> > ---
> >  block/io_uring.c | 12 +++++++++++-
> >  meson.build      |  1 +
> >  2 files changed, 12 insertions(+), 1 deletion(-)
>
> Thanks, applied to my block tree:
> https://gitlab.com/stefanha/qemu/commits/block
>

Great! Sorry about the mistake before. I'm flushed.


> Stefan