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Date: Mon, 24 Nov 2014 12:39:38 +0100
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v4 1/3] linux-aio: fix submit aio as a batch
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To: Ming Lei <ming.lei@canonical.com>, qemu-devel@nongnu.org, Stefan Hajnoczi <stefanha@redhat.com>, Kevin Wolf <kwolf@redhat.com>



On 24/11/2014 12:31, Ming Lei wrote:
> +static int ioq_enqueue(struct qemu_laio_state *s, struct iocb *iocb)
>  {
>      unsigned int idx = s->io_q.idx;
>  
> +    if (unlikely(idx == s->io_q.size)) {
> +        ioq_submit(s);
> +        return -EAGAIN;

Only return -EAGAIN if ioq_submit(s) returns 0?  Otherwise reload idx
and go on.

Paolo

> +    }
> +