[net,1/3] xen-netback: remove pointless clause from if statement

This patch removes a test in start_new_rx_buffer() that checks whether
a copy operation is less than MAX_BUFFER_OFFSET in length, since
MAX_BUFFER_OFFSET is defined to be PAGE_SIZE and the only caller of
start_new_rx_buffer() already limits copy operations to PAGE_SIZE or less.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Sander Eikelenboom <linux@eikelenboom.it>
---
 drivers/net/xen-netback/netback.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

On Thu, 2014-03-27 at 12:23 +0000, Paul Durrant wrote:
> This patch removes a test in start_new_rx_buffer() that checks whether
> a copy operation is less than MAX_BUFFER_OFFSET in length, since
> MAX_BUFFER_OFFSET is defined to be PAGE_SIZE and the only caller of
> start_new_rx_buffer() already limits copy operations to PAGE_SIZE or less.
> 
> Signed-off-by: Paul Durrant <paul.durrant@citrix.com>

Acked-by: Ian Campbell <ian.campbell@citrix.com>

Although it would have been nice to consider a BUG_ON or ASSERT.

> Cc: Wei Liu <wei.liu2@citrix.com>
> Cc: Sander Eikelenboom <linux@eikelenboom.it>
> ---
>  drivers/net/xen-netback/netback.c |    3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
> index 438d0c0..befc413 100644
> --- a/drivers/net/xen-netback/netback.c
> +++ b/drivers/net/xen-netback/netback.c
> @@ -192,8 +192,7 @@ static bool start_new_rx_buffer(int offset, unsigned long size, int head)
>  	 * into multiple copies tend to give large frags their
>  	 * own buffers as before.
>  	 */
> -	if ((offset + size > MAX_BUFFER_OFFSET) &&
> -	    (size <= MAX_BUFFER_OFFSET) && offset && !head)
> +	if ((offset + size > MAX_BUFFER_OFFSET) && offset && !head)
>  		return true;
>  
>  	return false;


--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Thursday, March 27, 2014, 1:23:06 PM, you wrote:

> This patch removes a test in start_new_rx_buffer() that checks whether
> a copy operation is less than MAX_BUFFER_OFFSET in length, since
> MAX_BUFFER_OFFSET is defined to be PAGE_SIZE and the only caller of
> start_new_rx_buffer() already limits copy operations to PAGE_SIZE or less.

> Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
> Cc: Ian Campbell <ian.campbell@citrix.com>
> Cc: Wei Liu <wei.liu2@citrix.com>
> Cc: Sander Eikelenboom <linux@eikelenboom.it>
> ---
>  drivers/net/xen-netback/netback.c |    3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)

> diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
> index 438d0c0..befc413 100644
> --- a/drivers/net/xen-netback/netback.c
> +++ b/drivers/net/xen-netback/netback.c
> @@ -192,8 +192,7 @@ static bool start_new_rx_buffer(int offset, unsigned long size, int head)
>          * into multiple copies tend to give large frags their
>          * own buffers as before.
>          */
> -       if ((offset + size > MAX_BUFFER_OFFSET) &&
> -           (size <= MAX_BUFFER_OFFSET) && offset && !head)
> +       if ((offset + size > MAX_BUFFER_OFFSET) && offset && !head)
>                 return true;
>  
>         return false;


Will put this through the test now ..

--
Sander

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html