Re: [PATCH 2/4] staging: r8188eu: reformat long computation lines

[Deepak R Varma]

On Tue, Oct 18, 2022 at 10:43:07PM -0700, Joe Perches wrote:
> On Tue, 2022-10-18 at 18:12 +0530, Deepak R Varma wrote:
> > On Tue, Oct 18, 2022 at 11:21:26AM +0000, David Laight wrote:
> > > From: Greg KH
> > > > Sent: 17 October 2022 15:10
> > > >
> > > > On Mon, Oct 17, 2022 at 06:52:50PM +0530, Deepak R Varma wrote:
> > > > > Reformat long running computation instructions to improve code readability.
> > > > > Address following checkpatch script complaints:
> > > > > 	CHECK: line length of 171 exceeds 100 columns
> > > > > 	CHECK: line length of 113 exceeds 100 columns
> []
> > > > > diff --git a/drivers/staging/r8188eu/core/rtw_br_ext.c b/drivers/staging/r8188eu/core/rtw_br_ext.c
> []
> > > > > @@ -211,8 +211,10 @@ static int __nat25_network_hash(unsigned char *network_addr)
> > > > >  	} else if (network_addr[0] == NAT25_IPX) {
> > > > >  		unsigned long x;
> > > > >
> > > > > -		x = network_addr[1] ^ network_addr[2] ^ network_addr[3] ^ network_addr[4] ^
> > > > network_addr[5] ^
> > > > > -			network_addr[6] ^ network_addr[7] ^ network_addr[8] ^ network_addr[9] ^
> > > > network_addr[10];
> > > > > +		x = network_addr[1] ^ network_addr[2] ^ network_addr[3] ^
> > > >
> > > > Why not go out to [4] here and then you are one line shorter?
> > >
> > > and/or use a shorter variable name....
> > Hi David,
> > I have already re-submitted the patch set with 4 in line arrangement. Do you
> > still suggest using shorter variable names?
>
> Assuming this code is not performance sensitive, I suggest not just
> molifying checkpatch but perhaps improving the code by adding a helper
> function something like:
>
> u8 xor_array_u8(u8 *x, size_t len)
> {
> 	size_t i;
> 	u8 xor = x[0];
>
> 	for (i = 1; i < len; i++)
> 		xor ^= x[i];
>
> 	return xor;
> }
>
> so for instance this could be:
>
> 		x = xor_array_u8(&network_addr[1], 10);
>

Hi Joe,
Great suggestion. Thank you.
Is there a way to confirm that this improvement won't impact performance? Will I
need any specific hardware / device to run tests?

./drv