block/io_uring: fix EINTR and resubmit short reads

[Qemu-devel] [PATCH 0/3] block/io_uring: fix EINTR and resubmit short reads

Posted by Stefan Hajnoczi 4 years, 9 months ago

Short reads are possible with cache=writeback (see Patch 3 for details).
Handle this by resubmitting requests until the read is completed.

Patch 1 adds trace events useful for debugging io_uring.

Patch 2 fixes EINTR.  This lays the groundwork for resubmitting requests in
Patch 3.

Aarushi: Feel free to squash this into your patch series if you are happy with
the code, I don't mind if the authorship information is lost.  After applying
these patches I can successfully boot a Fedora 30 guest qcow2 file with
cache=writeback.

Based-on: <20190610134905.22294-1-mehta.aaru20@gmail.com>

Stefan Hajnoczi (3):
  block/io_uring: add submission and completion trace events
  block/io_uring: fix EINTR request resubmission
  block/io_uring: resubmit short buffered reads

 block/io_uring.c   | 136 ++++++++++++++++++++++++++++++++++-----------
 block/trace-events |   6 +-
 2 files changed, 108 insertions(+), 34 deletions(-)

-- 
2.21.0

Re: [Qemu-devel] [Qemu-block] [PATCH 0/3] block/io_uring: fix EINTR and resubmit short reads

Posted by John Snow 4 years, 8 months ago


On 7/15/19 4:19 PM, Stefan Hajnoczi wrote:
> Short reads are possible with cache=writeback (see Patch 3 for details).
> Handle this by resubmitting requests until the read is completed.
> 
> Patch 1 adds trace events useful for debugging io_uring.
> 
> Patch 2 fixes EINTR.  This lays the groundwork for resubmitting requests in
> Patch 3.
> 
> Aarushi: Feel free to squash this into your patch series if you are happy with
> the code, I don't mind if the authorship information is lost.  After applying
> these patches I can successfully boot a Fedora 30 guest qcow2 file with
> cache=writeback.
> 
> Based-on: <20190610134905.22294-1-mehta.aaru20@gmail.com>
> 
> Stefan Hajnoczi (3):
>   block/io_uring: add submission and completion trace events
>   block/io_uring: fix EINTR request resubmission
>   block/io_uring: resubmit short buffered reads
> 
>  block/io_uring.c   | 136 ++++++++++++++++++++++++++++++++++-----------
>  block/trace-events |   6 +-
>  2 files changed, 108 insertions(+), 34 deletions(-)
> 

Since this is over the 30 days mark, I'm going to assume this WAS
squashed into Aarushi's patchset, and it's safe to drop this from the
review queue for now?

--js

Re: [Qemu-devel] [Qemu-block] [PATCH 0/3] block/io_uring: fix EINTR and resubmit short reads

Posted by Stefan Hajnoczi 4 years, 8 months ago

On Wed, Aug 21, 2019 at 06:20:39PM -0400, John Snow wrote:
> 
> 
> On 7/15/19 4:19 PM, Stefan Hajnoczi wrote:
> > Short reads are possible with cache=writeback (see Patch 3 for details).
> > Handle this by resubmitting requests until the read is completed.
> > 
> > Patch 1 adds trace events useful for debugging io_uring.
> > 
> > Patch 2 fixes EINTR.  This lays the groundwork for resubmitting requests in
> > Patch 3.
> > 
> > Aarushi: Feel free to squash this into your patch series if you are happy with
> > the code, I don't mind if the authorship information is lost.  After applying
> > these patches I can successfully boot a Fedora 30 guest qcow2 file with
> > cache=writeback.
> > 
> > Based-on: <20190610134905.22294-1-mehta.aaru20@gmail.com>
> > 
> > Stefan Hajnoczi (3):
> >   block/io_uring: add submission and completion trace events
> >   block/io_uring: fix EINTR request resubmission
> >   block/io_uring: resubmit short buffered reads
> > 
> >  block/io_uring.c   | 136 ++++++++++++++++++++++++++++++++++-----------
> >  block/trace-events |   6 +-
> >  2 files changed, 108 insertions(+), 34 deletions(-)
> > 
> 
> Since this is over the 30 days mark, I'm going to assume this WAS
> squashed into Aarushi's patchset, and it's safe to drop this from the
> review queue for now?

Yes, Aarushi included in the io_uring patch series.

Stefan