Re: [PATCH 2/3] pids: Split alloc_pidmap into parts

[Oleg Nesterov <oleg@redhat.com>]

On 11/10, Pavel Emelyanov wrote:
>
> The map's page allocation code is moved to separate function
> to make clone-with-pids patching simpler.

Sorry for the really cosmetic nit, but I simply can't resist...

> +static int alloc_pidmap_page(struct pidmap *map)
> +{
> +	void *page = kzalloc(PAGE_SIZE, GFP_KERNEL);
> +
> +	/*
> +	 * Free the page if someone raced with us
> +	 * installing it:
> +	 */
> +	spin_lock_irq(&pidmap_lock);
> +	if (!map->page) {
> +		map->page = page;
> +		page = NULL;
> +	}
> +	spin_unlock_irq(&pidmap_lock);
> +	kfree(page);
> +
> +	return map->page ? 0 : -1;

Again, I won't insist, but "return !map->page" looks more readable.
Even better (imho) would be to return map->page, and change the
single caller to check "if (!alloc_pidnap_page())".

Oleg.