Re: [PATCH v3 5/5] block-coroutine-wrapper: use qemu_get_current_aio_context()

[Eric Blake]

On Tue, Sep 12, 2023 at 07:10:37PM -0400, Stefan Hajnoczi wrote:
> Use qemu_get_current_aio_context() in mixed wrappers and coroutine
> wrappers so that code runs in the caller's AioContext instead of moving
> to the BlockDriverState's AioContext. This change is necessary for the
> multi-queue block layer where any thread can call into the block layer.
> 
> Most wrappers are IO_CODE where it's safe to use the current AioContext
> nowadays. BlockDrivers and the core block layer use their own locks and
> no longer depend on the AioContext lock for thread-safety.
> 
> The bdrv_create() wrapper invokes GLOBAL_STATE code. Using the current
> AioContext is safe because this code is only called with the BQL held
> from the main loop thread.
> 
> The output of qemu-iotests 051 is sensitive to event loop activity.
> Update the output because the monitor BH runs at a different time,
> causing prompts to be printed differently in the output.
> 
> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
> ---
>  scripts/block-coroutine-wrapper.py | 6 ++----
>  tests/qemu-iotests/051.pc.out      | 4 ++--
>  2 files changed, 4 insertions(+), 6 deletions(-)
> 

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

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