Re: [PATCH 08/12] aio: remove aio_context_acquire()/aio_context_release() API

[Eric Blake <eblake@redhat.com>]

On Wed, Nov 29, 2023 at 02:55:49PM -0500, Stefan Hajnoczi wrote:
> Delete these functions because nothing calls these functions anymore.
> 
> I introduced these APIs in commit 98563fc3ec44 ("aio: add
> aio_context_acquire() and aio_context_release()") in 2014. It's with a
> sigh of relief that I delete these APIs almost 10 years later.
> 
> Thanks to Paolo Bonzini's vision for multi-queue QEMU, we got an
> understanding of where the code needed to go in order to remove the
> limitations that the original dataplane and the IOThread/AioContext
> approach that followed it.
> 
> Emanuele Giuseppe Esposito had the splendid determination to convert
> large parts of the codebase so that they no longer needed the AioContext
> lock. This was a painstaking process, both in the actual code changes
> required and the iterations of code review that Emanuele eeked out of

s/eeked/eked/

> Kevin and me over many months.
> 
> Kevin Wolf tackled multitudes of graph locking conversions to protect
> in-flight I/O from run-time changes to the block graph as well as the
> clang Thread Safety Analysis annotations that allow the compiler to
> check whether the graph lock is being used correctly.
> 
> And me, well, I'm just here to add some pizzazz to the QEMU multi-queue
> block layer :). Thank you to everyone who helped with this effort,
> including Eric Blake, code reviewer extraordinaire, and others who I've
> forgotten to mention.
> 
> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
> ---
>  include/block/aio.h | 17 -----------------
>  util/async.c        | 10 ----------
>  2 files changed, 27 deletions(-)
>

Yay!

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.
Virtualization:  qemu.org | libguestfs.org