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Date: Thu, 16 Oct 2025 13:12:48 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Quanmin Yan <yanquanmin1@huawei.com>
Cc: <sj@kernel.org>, <damon@lists.linux.dev>,
 <linux-kernel@vger.kernel.org>, <linux-mm@kvack.org>,
 <wangkefeng.wang@huawei.com>, <zuoze1@huawei.com>
Subject: Re: [PATCH] mm/damon: add a min_sz_region parameter to
 damon_set_region_biggest_system_ram_default()
Message-Id: <20251016131248.f74041dd236ca33808a07ba4@linux-foundation.org>
In-Reply-To: <20251016104717.2194909-1-yanquanmin1@huawei.com>
References: <20251016104717.2194909-1-yanquanmin1@huawei.com>
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On Thu, 16 Oct 2025 18:47:17 +0800 Quanmin Yan <yanquanmin1@huawei.com> wrote:

> After adding addr_unit support for DAMON_LRU_SORT and DAMON_RECLAIM,
> the related region setup now requires alignment based on min_sz_region.

Why?

Presumably the current code causes some sort of user-visible
misbehavior.  Please include a description of that misbehavior and of
how users might trigger it.

> Add min_sz_region to damon_set_region_biggest_system_ram_default()
> and use it when calling damon_set_regions(), replacing the previously
> hardcoded DAMON_MIN_REGION.
>