Re: [Unionfs] Re: [-mm patch] UNION_FS must depend on SLAB

[hooanon05@yahoo.co.jp]

Josef Sipek:
> That's the only user of malloc_sizes. It is supposed to be an optimization -
> we get the smallest sized piece of memory even if we don't need all of it.
> This way we don't reallocate & memcpy needlessly.

How about exporting ksize to modules, and introduce a new function such
like this?
Of course, adding gfp_t to its parameter list make this function more generic.

void *kzrealloc(void *p, int nused, int new_sz)
{
	void *q;

	if (new_sz <= nused)
		return p;
	if (new_sz <= ksize(p)) {
		memset(p + nused, 0, new_sz - nused);
		return p;
	}

	q = kmalloc(new_sz, GFP_KERNEL);
	if (unlikely(!q))
		return NULL;
	memcpy(q, p, nused);
	memset(q + nused, 0, new_sz - nused);
	kfree(p);
	return q;
}


Junjiro Okajima