Re: [Qemu-devel] [PATCH 05/18] block/mirror: Convert to coroutines

[Kevin Wolf <kwolf@redhat.com>]

Am 13.09.2017 um 20:18 hat Max Reitz geschrieben:
> In order to talk to the source BDS (and maybe in the future to the
> target BDS as well) directly, we need to convert our existing AIO
> requests into coroutine I/O requests.
> 
> Signed-off-by: Max Reitz <mreitz@redhat.com>

Please follow through with it and add a few patches that turn it into
natural coroutine code rather than just any coroutine code. I know I did
the same kind of half-assed conversion in qed, but mirror is code that
is actually used and that people look at for more than just a bad
example.

You'll probably notice more things when you do this, but the obvious
things would be changing mirror_co_read() into a mirror_co_copy() with
the former callbacks inlined; keeping op on the stack instead of
mallocing it in mirror_perform() and free it deep inside the nested
functions that used to be callbacks; and probably also cleaning up the
random calls to aio_context_acquire/release() that will now appear in
the middle of the function.

Anyway, that's for follow-up patches (though ideally in the same
series), so for this one you can have:

Reviewed-by: Kevin Wolf <kwolf@redhat.com>