Re: [Qemu-devel] [PATCH][RFC] Linux AIO support when using O_DIRECT

[Avi Kivity]

Anthony Liguori wrote:
> This is just a first cut.  It needs a fair bit of cleanup before it can be
> committed.  I also think we need to fixup the AIO abstractions a bit.
>
> I wanted to share though in case anyone is interested in doing some performance
> comparisons.  It seems to work although I haven't exercised it very much.
>
>  
> +typedef struct AIOOperations
> +{
> +    struct qemu_aiocb *(*get_aiocb)(void);
> +    void (*put_aiocb)(struct qemu_aiocb *);
> +    int (*read)(struct qemu_aiocb *);
> +    int (*write)(struct qemu_aiocb *);
> +    int (*error)(struct qemu_aiocb *);
> +    ssize_t (*get_result)(struct qemu_aiocb *aiocb);
> +    int (*cancel)(int fd, struct qemu_aiocb *aiocb);
> +} AIOOperations;
> +
>   


Instead of introducing yet another layer of indirection, you could add 
block-raw-linux-aio, which would be registered before block-raw-posix 
(which is realy block-raw-threadpool...), and resist a ->probe() if 
caching is enabled.

--
error compiling committee.c: too many arguments to function