Re: [-mm patch] make kcalloc() a static inline

[Denis Vlasenko <vda@ilport.com.ua>]

> > static inline void *kcalloc(size_t n, size_t size, unsigned int __nocast flags)
> > {
> > 	if (__builtin_constant_p(n)) {
> > 		if (n != 0 && size > INT_MAX / n)
> > 			return NULL;
> > 		return kzalloc(n * size, flags);
> > 	}
> > 	return kcalloc_helper(n, size, flags);
> > }
> > 
> > void *kcalloc_helper(size_t n, size_t size, unsigned int __nocast flags)
> > {
> > 	if (n != 0 && size > INT_MAX / n)
> > 		return NULL;
> > 	return kzalloc(n * size, flags);
> > }
> 
> That's extra complexity and code duplication. How much do we shave off 
> kernel text of allyesconfig with this?
> 
> Please note that whenever the caller does proper bounds checking, GCC can 
> optimize the security check away. Therefore, in practice, we don't spread 
> around the extra operations so much, I think.

gcc can optimize that away with non-const n?! I don't think so.
--
vda

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