From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta1.migadu.com (out-242.mta1.migadu.com [95.215.58.242]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4004642D77B for ; Tue, 25 Aug 2026 12:39:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.242 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787661575; cv=none; b=MoJ8m1We2TRufdl3mJ+SToONJwMjVkObU15Gb+Xu2LZD+tERZ1EX7/MA/regu6ODoQoYVvC49ANjHrxfYcaRNxD4MPeKFxnDqFRNRs6QZKxmNOVclArch76/skgpcqHGQNIDBkyaKFPtxagwxDcEmw8IIXp2rt/f79qlzi9NQuw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787661575; c=relaxed/simple; bh=Pzwlf//Bvy46LelD2lYa9+LILpMnz7M9KVbRyTt1z78=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=BLqTKEPDQc9LebHFh2sA+tiRR+pf9EOz9u9gpH5N5Uzl9Tvb+u6Atr7cOGRVEGcGzoMHT3nGgG3u9mlsm2AbXxu3JRofat+2pGiEqVTOTXmHhsdouWJZjvazPpcCDOTKqu1szd0EQHK0ZjxFVTaxk323kaYqXxJwRfLp/ltfNGI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=bu+zn39Z; arc=none smtp.client-ip=95.215.58.242 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="bu+zn39Z" X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=Pzwlf//Bvy46LelD2lYa9+LILpMnz7M9KVbRyTt1z78=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1787661562; v=1; x=1788266362; b=bu+zn39ZAmUhPMP6eQi4M856XzugIccqrAw1XhWUv1Ex+I7DIaQW4JgQm86+SwB/WwVZ3wrz jWMIt81tTErULxqy1vGgVJi8WxZSdgPl/36h5mTn+QXC76zisRtNRPyQ0xt5g5XcjQ32trZcluF Xe3384+5ftrB4yyN241LnVRo= X-Envelope-To: linux-kernel@vger.kernel.org Received: from [10.254.116.35] (101.126.56.83) by smtp.migadu.com with ESMTPS id a43f18b9a5ea956e; Tue, 25 Aug 2026 12:39:12 +0000 X-Mizu-Trace-ID: a43f18b9a5ea956e X-Migadu-Flow: FLOW_OUT Message-ID: <59e0f96f-6405-4e7c-9561-456f18a658b8@linux.dev> Date: Tue, 25 Aug 2026 20:38:52 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 08/17] mm/sparse-vmemmap: support section-based vmemmap optimization To: Muchun Song , Andrew Morton , Oscar Salvador , David Hildenbrand Cc: Mike Rapoport , Vlastimil Babka , Lorenzo Stoakes , Michal Hocko , David Laight , "Liam R . Howlett" , Suren Baghdasaryan , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Muchun Song References: <20260825084608.47437-1-songmuchun@bytedance.com> <20260825084608.47437-9-songmuchun@bytedance.com> From: Qi Zheng In-Reply-To: <20260825084608.47437-9-songmuchun@bytedance.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 8/25/26 4:45 PM, Muchun Song wrote: > Teach sparse-vmemmap population code to use the compound page order > when deciding whether a vmemmap page can be optimized. > > With this information, the common sparse-vmemmap population path can > allocate or reuse shared tail vmemmap pages directly instead of relying > on HugeTLB-specific handling. > > This centralizes vmemmap optimization logic in the sparse-vmemmap code, > based on section metadata, and prepares for sharing the same mechanism > across different users of vmemmap optimization, including HugeTLB and > DAX. > > Signed-off-by: Muchun Song Acked-by: Qi Zheng Thanks, Qi