Re: [patch cr 2/4] [RFC] syscalls, x86: Add __NR_kcmp syscall v7

[Cyrill Gorcunov]

On Fri, Feb 03, 2012 at 01:22:41AM -0800, Andrew Morton wrote:
> On Fri, 3 Feb 2012 10:09:29 +0100 Ingo Molnar <mingo@xxxxxxx> wrote:
> 
> > 
> > * Cyrill Gorcunov <gorcunov@xxxxxxxxxx> wrote:
> > 
> > > > > +			get_random_bytes(&cookies[i][j],
> > > > > +					 sizeof(cookies[i][j]));
> > > > 
> > > > ugly line break.
> > > > 
> > > 
> > > Why? Looks pretty good to me. But sure I'll change it.
> > 
> > It's ugly because it serves no purpose other than pacifying 
> > checkpatch and makes the code *uglier*.
> 
> No it doesn't.  For 80-col displays the code is *already wrapped*.  And
> that wrapping to column 0 is vastly worse than the above.
> 
> If we want to increase the standard to (say) 96 cols then fine, I'd be
> happy with that.  But until we do that we should not create such a
> gruesome mess for those who use 80 cols.
> 
> > It's a disease. When checkpatch tells you "this line is too 
> > long" then consider it a code cleanliness warning!
> 
> Well yes, if it can be fixed by other means then great.
> 

Guys, I simply made it as

static __init int kcmp_cookie_init(void)
{
	int i, j;

	for (i = 0; i < KCMP_TYPES; i++) {
		for (j = 0; j < 2; j++)
			get_random_bytes(&cookies[i][j], sizeof(long));
		cookies[i][1] |= (~(~0UL >>  1) | 1);
	}

	return 0;
}

I thought in first place that sizeof(cookies[i][j]) would allow me
to change type of cookies in one place (ie at declaration) but
if cookies type will be changed -- the code will need careful review
anway, so sizeof(long) will be enough I think.

On the other hands, maybe more clean variant will be

static __init int kcmp_cookie_init(void)
{
	const int size = sizeof(cookies[0][0]);
	int i, j;

	for (i = 0; i < KCMP_TYPES; i++) {
		for (j = 0; j < 2; j++)
			get_random_bytes(&cookies[i][j], size);
		cookies[i][1] |= (~(~0UL >>  1) | 1);
	}

	return 0;
}

Hm?

	Cyrill
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