Re: [PATCH] xen-blkback: define pr_fmt macro to avoid the duplication of DRV_PFX

["Roger Pau Monné" <roger.pau@citrix.com>]

El 31/03/15 a les 23.14, Tao Chen ha escrit:
> Define pr_fmt macro with {xen-blkback: } prefix, then remove all use
> of DRV_PFX in the pr and DPRINTK sentences. It will simplify the code.
> 
> And if the pr sentences miss a \n, add it in the end. If the DPRINTK
> sentences have redundant \n, remove it. It will format the code.
> 
> These all make the readability of the code become better.

Thanks for the patch.

> Signed-off-by: Tao Chen <boby.chen@huawei.com>
> ---
>  drivers/block/xen-blkback/blkback.c | 62 ++++++++++++++++++-------------------
>  drivers/block/xen-blkback/common.h  |  6 ----
>  drivers/block/xen-blkback/xenbus.c  | 18 ++++++-----
>  3 files changed, 42 insertions(+), 44 deletions(-)
> 
[...]
> diff --git a/drivers/block/xen-blkback/common.h b/drivers/block/xen-blkback/common.h
> index 375d288..f620b5d 100644
> --- a/drivers/block/xen-blkback/common.h
> +++ b/drivers/block/xen-blkback/common.h
> @@ -44,12 +44,6 @@
>  #include <xen/interface/io/blkif.h>
>  #include <xen/interface/io/protocols.h>
>  
> -#define DRV_PFX "xen-blkback:"
> -#define DPRINTK(fmt, args...)				\
> -	pr_debug(DRV_PFX "(%s:%d) " fmt ".\n",		\
> -		 __func__, __LINE__, ##args)
> -
> -
>  /*
>   * This is the maximum number of segments that would be allowed in indirect
>   * requests. This value will also be passed to the frontend.
> diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c
> index b33083e..0dbbfeb 100644
> --- a/drivers/block/xen-blkback/xenbus.c
> +++ b/drivers/block/xen-blkback/xenbus.c
> @@ -14,6 +14,11 @@
>  
>  */
>  
> +#define pr_fmt(fmt) "xen-blkback: " fmt
> +#define DPRINTK(fmt, args...)			\
> +	pr_debug("(%s:%d) " fmt ".\n",		\
> +		__func__, __LINE__, ##args)
> +
>  #include <stdarg.h>
>  #include <linux/module.h>
>  #include <linux/kthread.h>
> @@ -426,14 +431,14 @@ static int xen_vbd_create(struct xen_blkif *blkif, blkif_vdev_t handle,
>  				 FMODE_READ : FMODE_WRITE, NULL);
>  
>  	if (IS_ERR(bdev)) {
> -		DPRINTK("xen_vbd_create: device %08x could not be opened.\n",
> +		DPRINTK("xen_vbd_create: device %08x could not be opened",
>  			vbd->pdevice);
>  		return -ENOENT;
>  	}
>  
>  	vbd->bdev = bdev;
>  	if (vbd->bdev->bd_disk == NULL) {
> -		DPRINTK("xen_vbd_create: device %08x doesn't exist.\n",
> +		DPRINTK("xen_vbd_create: device %08x doesn't exist",
>  			vbd->pdevice);

IMHO this two above should be made a pr_warn probably...

>  		xen_vbd_free(vbd);
>  		return -ENOENT;
> @@ -452,7 +457,7 @@ static int xen_vbd_create(struct xen_blkif *blkif, blkif_vdev_t handle,
>  	if (q && blk_queue_secdiscard(q))
>  		vbd->discard_secure = true;
>  
> -	DPRINTK("Successful creation of handle=%04x (dom=%u)\n",
> +	DPRINTK("Successful creation of handle=%04x (dom=%u)",
>  		handle, blkif->domid);

...and this should be turned into a plain pr_debug. And with that we can
get rid of DPRINTK.

Roger.