From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 2DD013E3142 for ; Wed, 29 Jul 2026 08:52:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785315134; cv=none; b=rFon5X+mK0PyHwNGbLkLDz2v9ZCsBkSM0LPviGsTLGWZff6UMGkT2FAAxi9aZZ2v5HZVS8y6CPKZOqoML9eLp02jKaY28L744GMoWgz7Etmj/wGYu+BpBPPNoeInO3pSQX96FeYU/bNQsQA0tj7CACQ9wexqr4zbphhZvwgYWKw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785315134; c=relaxed/simple; bh=8aCx8tc8MvtsB4hJgg63jPXKz9/8serj6hBiHKcWXNQ=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Rc1QctYXLesCZ9QeFvKSB7ncAghpCPsdHdFBFhAleHmWthZMlx8y6NAknJKdREYeEaL/DvrD8eb7fh+PaICcpeAyCq5cu2paxLpM2m21Y0gZ20IKKCE5pvN88e2g4A+fOJ0mZ8O4JylW/UKtJeXELiGJqL/B7zOuqMQYTkDlddc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=SMBofCzT; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="SMBofCzT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 19DF91F000E9; Wed, 29 Jul 2026 08:52:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785315133; bh=lYCRDETS5dI5i7sQBYk0JlztdxKG736m3ZWnBU7yY08=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=SMBofCzTBEg/3tHBjKYQzFrRPZgXFQ4Vi6xJLpf5IJf0vlWxsnprH1FKf5OYoVFlK 1hRCzkpNh+Lvt/LkZyjPPYNWFQ5DigcPjoW17VyqS8ZKP0io1czw9RgqXURhYlVFKV 7KL5++EJruR6tHPa5B5dBnAJrFQQCuV4iK5aKdHCWxaf4uEDNvNPa/tSfAL1ZUkrH+ MrfWXvF8q9vIhBGmndVyDm3DjcFSLGghszFtk5yPfI93FOJaV4Xs0tcs/QCY0E7d4O q03KOOwiPe7D59XDUHXJL8uI5n5VlE9yENkX7IP3nYTAcL9VJZkXQOyRseK6clRd0m RhKI2n0Eo//iw== Message-ID: Date: Wed, 29 Jul 2026 10:52:09 +0200 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 v2] mm/hugetlb_cma: support percentage-based hugetlb_cma reservation To: Sourav Panda , muchun.song@linux.dev, osalvador@suse.de, akpm@linux-foundation.org Cc: surenb@google.com, fvdl@google.com, gthelen@google.com, rientjes@google.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20260628190155.3655895-1-souravpanda@google.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 6/28/26 21:01, Sourav Panda wrote: > Currently, hugetlb_cma reservation only supports absolute sizes (e.g., > hugetlb_cma=2G or hugetlb_cma=0:1G,1:1G). This can be restrictive in > heterogeneous environments or when deploying common kernel command lines > across machines with different memory capacities. > > Add support for percentage-based hugetlb_cma reservation (e.g., > hugetlb_cma=20% or hugetlb_cma=0:20%,1:10%). > > The percentage is calculated against the total memory (for global > settings) or against the node-specific memory (for node-specific > settings) using memblock APIs during early boot. > > Signed-off-by: Sourav Panda > Reported-by: kernel test robot > Closes: https://lore.kernel.org/oe-kbuild-all/202606262023.IKUrn01I-lkp@intel.com/ > --- > Link: https://lore.kernel.org/linux-mm/20260625215900.2151690-1-souravpanda@google.com/ [v1] > > v2: > - Use mul_u64_u32_div() instead of mult_frac() to avoid 64-bit division on 32-bit architectures (Reported by kernel test robot). > - Fix physical memory size truncation on 32-bit PAE by using phys_addr_t in memblock_node_memory_size() (Sashiko). > - Fix boot parameter override logic to respect standard last-one-wins precedence by clearing opposite values during parsing and clearing node-specific values when global values are parsed. > .../admin-guide/kernel-parameters.txt | 7 +- > mm/hugetlb_cma.c | 96 ++++++++++++++++++- > 2 files changed, 97 insertions(+), 6 deletions(-) What's the status of this? Reading the comments I assume a v3? -- Cheers, David