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Date: Wed, 29 Aug 2012 13:11:39 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v3 2/5] [RFC] libqblock, user example
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To: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Cc: kwolf@redhat.com, aliguori@us.ibm.com, stefanha@gmail.com, qemu-devel@nongnu.org, blauwirbel@gmail.com, eblake@redhat.com, afaerber@suse.de

Il 29/08/2012 13:05, Wenchao Xia ha scritto:
> +    printf("checking aio status for %d times.\n", check_times);
> +    while (true == qb_aio_check(broker)) {
> +        check_times++;
> +        usleep(1);
> +    }
> +

Busy waiting is not acceptable, and this is the reason why I had
suggested to keep AIO out of the design for now.

You need to provide an implementation of AIO for either glib or
something else, but this is best done within QEMU first (and only later
moved to libqblock).

Paolo