Re: [Qemu-devel] [RFC 2/5] aio: Add io_read_poll() callback

[Paolo Bonzini]

Il 31/05/2014 20:43, Max Reitz ha scritto:
> @@ -108,7 +120,9 @@ bool aio_pending(AioContext *ctx)
>          int revents;
>
>          revents = node->pfd.revents & node->pfd.events;
> -        if (revents & (G_IO_IN | G_IO_HUP | G_IO_ERR) && node->io_read) {
> +        if (revents & (G_IO_IN | G_IO_HUP | G_IO_ERR) && node->io_read &&
> +            (!node->io_read_poll || node->io_read_poll(node->opaque)))
> +        {
>              return true;
>          }

This would cause a busy loop whenever io_read_poll returns false.  You 
would  need to call io_read_poll when you fill the pollfds array, i.e. 
in aio_poll and aio_ctx_prepare.

Paolo