Re: [Qemu-block] [PATCH 2/2] virtio-blk: Inline request init, complete and free functions

[Laszlo Ersek]

On 02/07/17 14:27, Fam Zheng wrote:
> These are used in each request handling, inline them.
> 
> Signed-off-by: Fam Zheng <address@hidden>
> ---
>  hw/block/virtio-blk.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
> index 2858c31..1da9570 100644
> --- a/hw/block/virtio-blk.c
> +++ b/hw/block/virtio-blk.c
> @@ -29,8 +29,8 @@
>  #include "hw/virtio/virtio-bus.h"
>  #include "hw/virtio/virtio-access.h"
>  
> -static void virtio_blk_init_request(VirtIOBlock *s, VirtQueue *vq,
> -                                    VirtIOBlockReq *req)
> +static inline void virtio_blk_init_request(VirtIOBlock *s, VirtQueue *vq,
> +                                           VirtIOBlockReq *req)
>  {
>      req->dev = s;
>      req->vq = vq;
> @@ -40,12 +40,13 @@ static void virtio_blk_init_request(VirtIOBlock *s, 
> VirtQueue *vq,
>      req->mr_next = NULL;
>  }
>  
> -static void virtio_blk_free_request(VirtIOBlockReq *req)
> +static inline void virtio_blk_free_request(VirtIOBlockReq *req)
>  {
>      g_free(req);
>  }
>  
> -static void virtio_blk_req_complete(VirtIOBlockReq *req, unsigned char 
> status)
> +static inline void virtio_blk_req_complete(VirtIOBlockReq *req,
> +                                           unsigned char status)
>  {
>      VirtIOBlock *s = req->dev;
>      VirtIODevice *vdev = VIRTIO_DEVICE(s);
> 

Hm, virtio_blk_req_complete() looks a bit too "meaty" and seems to be
called from a little too many places for me to feel convenient about
inlining it. I guess I'd leave it to the compiler to optimize the
function call. Does the explicit hint offer a noticeable perf improvement?

Inlining virtio_blk_free_request() looks reasonable.

virtio_blk_init_request() looks okay too.

Other reviewers should feel free to override my concerns :) My view on
this is distant.

Thanks
Laszlo