From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 09CF127FB0E; Wed, 18 Mar 2026 19:50:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773863408; cv=none; b=pWGk2TKmyU+nqOI1frBAkZ/fO1Hp8OKfQX1CcWk3Y3okDvJOqY1a+v+DhlT7KvFOG6N4hKyNxVKRjRFGq+8nGDHPbsSIvFAqMPsNyRY5m/QPbWGox7QMHyorbejifmKN1XYGr903g4GZoMAwKEGF5Ycbsau866MRBFA1bEQbUuk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773863408; c=relaxed/simple; bh=aBpoyvqo/+v2d6P9WhuCifdS3XmIawtvNpv71rMyyaA=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=clJ7KG97I9dRuUCe9cr5xWLRxak3yPAS9U4LvuF74HsYZJMrFaQkkBCShyFWhX1SmYrvFpUpdfF3XXjf/PAosjRN4IoFKil1V16GDgcqKtTlb0k+ceL2lzN38b1evO0G9ZGoRnv1IGvVT9xRnazFhT98nkayUZiNVkU9U8IXdCc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=YxGhvUaN; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="YxGhvUaN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D18B2C19421; Wed, 18 Mar 2026 19:49:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773863407; bh=aBpoyvqo/+v2d6P9WhuCifdS3XmIawtvNpv71rMyyaA=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=YxGhvUaNTocIkJZunC5vXUOgkTErMFxp4CbFY9jx7JCWxCeQGIz8HJ2OUIUkqOhL7 ZrORxqhDaEfi/u7zp0r8Jp9kQE/5XTZw6dOVmgOgig30Bki736Eqm4VevTIvfmshNT rWzMFyDljK0zd+qeMwbmCx7UFJJVLB3Uc+4Vmy2JGjBm6DeGabx+2QDPdTGIdfUw1z GeSfSbMYsmoORs88eAwr00VM6k1dGtQH0GPTiRcF6Xz546K2rFrS96tWARQzwin49e T2kaf4E+NAKEUVKe3hGLybUcHNEoOE4QRgASXtYf9xUVlUD0HUIbFteFN5m2NI9cA0 Sx26EqYHO3Fog== Message-ID: <5ecb772b-2f2f-4010-aa6e-8894d188ea10@kernel.org> Date: Wed, 18 Mar 2026 20:49:52 +0100 Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH mm-unstable v15 13/13] Documentation: mm: update the admin guide for mTHP collapse To: Nico Pache , "Lorenzo Stoakes (Oracle)" Cc: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-trace-kernel@vger.kernel.org, aarcange@redhat.com, akpm@linux-foundation.org, anshuman.khandual@arm.com, apopple@nvidia.com, baohua@kernel.org, baolin.wang@linux.alibaba.com, byungchul@sk.com, catalin.marinas@arm.com, cl@gentwo.org, corbet@lwn.net, dave.hansen@linux.intel.com, dev.jain@arm.com, gourry@gourry.net, hannes@cmpxchg.org, hughd@google.com, jack@suse.cz, jackmanb@google.com, jannh@google.com, jglisse@google.com, joshua.hahnjy@gmail.com, kas@kernel.org, lance.yang@linux.dev, Liam.Howlett@oracle.com, lorenzo.stoakes@oracle.com, mathieu.desnoyers@efficios.com, matthew.brost@intel.com, mhiramat@kernel.org, mhocko@suse.com, peterx@redhat.com, pfalcato@suse.de, rakie.kim@sk.com, raquini@redhat.com, rdunlap@infradead.org, richard.weiyang@gmail.com, rientjes@google.com, rostedt@goodmis.org, rppt@kernel.org, ryan.roberts@arm.com, shivankg@amd.com, sunnanyong@huawei.com, surenb@google.com, thomas.hellstrom@linux.intel.com, tiwai@suse.de, usamaarif642@gmail.com, vbabka@suse.cz, vishal.moola@gmail.com, wangkefeng.wang@huawei.com, will@kernel.org, willy@infradead.org, yang@os.amperecomputing.com, ying.huang@linux.alibaba.com, ziy@nvidia.com, zokeefe@google.com, Bagas Sanjaya References: <20260226031741.230674-1-npache@redhat.com> <20260226032706.234519-1-npache@redhat.com> <638caee3-af71-47c7-bdc8-a905d3143387@lucifer.local> <1adffe75-cc91-4c55-bde7-9406bf656c72@redhat.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 3/18/26 20:08, Nico Pache wrote: > > > On 3/17/26 5:02 AM, Lorenzo Stoakes (Oracle) wrote: >> On Wed, Feb 25, 2026 at 08:27:06PM -0700, Nico Pache wrote: >>> Now that we can collapse to mTHPs lets update the admin guide to >>> reflect these changes and provide proper guidance on how to utilize it. >>> >>> Reviewed-by: Bagas Sanjaya >>> Signed-off-by: Nico Pache >> >> LGTM, but maybe we should mention somewhere about mTHP's max_ptes_none >> behaviour? > > IIRC we decided to strictly leave that out of the manual. I used to have it in > here. @david? I think we argued in the past that we didn't want to document the weird scaling part. Documenting that only two values are currently supported (no scaling) makes sense to me. -- Cheers, David