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From: Baoquan He <baoquan.he@linux.dev>
To: Youngjun Park <youngjun.park@lge.com>
Cc: akpm@linux-foundation.org, chrisl@kernel.org, linux-mm@kvack.org,
	cgroups@vger.kernel.org, linux-kernel@vger.kernel.org,
	kasong@tencent.com, hannes@cmpxchg.org, mhocko@kernel.org,
	roman.gushchin@linux.dev, shakeel.butt@linux.dev,
	muchun.song@linux.dev, shikemeng@huaweicloud.com, nphamcs@gmail.com,
	bhe@redhat.com, baohua@kernel.org, gunho.lee@lge.com,
	taejoon.song@lge.com, hyungjun.cho@lge.com, mkoutny@suse.com,
	baver.bae@lge.com, matia.kim@lge.com
Subject: Re: [PATCH v6 1/4] mm: swap: introduce swap tier infrastructure
Message-ID: <ahTTv5OWpaUF6S1S@MiWiFi-R3L-srv>
References: <20260421055323.940344-1-youngjun.park@lge.com>
 <20260421055323.940344-2-youngjun.park@lge.com>
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On 04/21/26 at 02:53pm, Youngjun Park wrote:
...snip...
> +bool swap_tiers_validate(void)
> +{
> +	struct swap_tier *tier;
> +
> +	/*
> +	 * Initial setting might not cover DEF_SWAP_PRIO.
> +	 * Swap tier must cover the full range (DEF_SWAP_PRIO to SHRT_MAX).
> +	 */

If so, do we need check if the upmost boundary SHRT_MAX is covered?

> +	if (swap_tier_is_active()) {
> +		tier = list_last_entry(&swap_tier_active_list,
> +			struct swap_tier, list);
> +
> +		if (tier->prio != DEF_SWAP_PRIO)
> +			return false;
> +	}
> +
> +	return true;
> +}
...snip...