Re: [Qemu-devel] [PATCH 0/3] better I/O accounting

[Stefan Hajnoczi]

This change requires that callers manage the accounting cookie.  I
think this belongs in block.c to make the life of callers easier.

Today block.c doesn't track requests and pretty much lets the
BlockDriver control the BlockDriverAIOCB.  But the request metadata
(timestamp, operation type, number of bytes) could all be part of the
BlockDriverAIOCB.  block.c also needs to interpose a cb function so
that it can account when the request completes.  Doing this all once
seems like the right way to go.

Stefan