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smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=gZDEJiGi; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 298D7606A321 for ; Wed, 21 Oct 2026 09:32:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=gZDEJiGi Received: by smtp.kernel.org (Postfix) with ESMTPSA id A074F1F000C9; Wed, 21 Oct 2026 09:32:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792575125; bh=QBfPB6VG09nH9ZMSi9s+AuhJxAnfHm47tgfC2i8+kBg=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=gZDEJiGiy/W+SSFO1BQYcsSqY/klq/62RfPYVvYA3ujxlE9ctXqvA3k3EfVQJtt4S j7sR5PEFVFNZp03AcUBVdxM1C2ro27eT+aQJw6gzbwEsuPMi7RK5LE8UMNsQLvQH8/ M1hX+mbFoojuJ8LqbivmexA+v4X0Qv2Qlw10uLnNkApo62qWQGbqI/YJaJDmuKEk2h sgXEIHyQNXbXgKn/NrrwK0C50CsaSDL+59fX1HuEBUz5/DrFJ3bekgWgdVsCLnV6jP dQT6JQ1tRp4Ue/v6Wc+CBW8M0KiPPlLGw0jhJkviAl/Hm94E/Qny4V3aHcK7KRslGC hbC2NKJX7RmIA== Message-ID: Date: Wed, 21 Oct 2026 11:31:59 +0200 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH v2 0/4] mm: compaction: mTHP-friendly memory compaction To: Bo Zhang Cc: akpm@linux-foundation.org, david@kernel.org, surenb@google.com, mhocko@suse.com, brendan.jackman@linux.dev, hannes@cmpxchg.org, ziy@nvidia.com, ljs@kernel.org, liam@infradead.org, rppt@kernel.org, qi.zheng@linux.dev, shakeel.butt@linux.dev, kasong@tencent.com, baohua@kernel.org, axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com, zhaonanzhe@xiaomi.com, lipengfei28@xiaomi.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <11264869-00ad-44ea-b39c-a78347af0ee1@kernel.org> <20261021060059.2253219-1-zhangbo56@xiaomi.com> From: "Vlastimil Babka (SUSE)" Content-Language: en-US Autocrypt: addr=vbabka@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 10/21/26 08:00, Bo Zhang wrote: > On 10/20/26 16:52, Vlastimil Babka (SUSE) wrote: >> Isn't using struct compact_control clean enough? There's already many >> fields like >> bool direct_compaction; /* False from kcompactd or /proc/... */ >> bool proactive_compaction; /* kcompactd proactive compaction */ >> >> Who says is_via_compact_memory() cannot be refactored into something using >> these kinds of fields and not 'order' being -1, which could be then used as >> the target order. > > Thanks, that's a much cleaner direction than reading huge_anon_orders_always > and would also address the race I raised in the second open question. > > I tried to work out what it takes, and ran into one thing I'd like your > opinion on before committing to an approach. I'm not going to answer your LLM's questions for you.