From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 A3C391CD0C for ; Mon, 15 Jul 2024 16:13:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721060008; cv=none; b=cfIUh0/8kuX9+Iv1U45LhUoDjN6gLHXO4MA2DZ8BPznM+KKSbcB2TUn/+lQVCtpRmU/bpSmvxnsMvZ+N0mHaMAKdAoukmVgVJSgJ9el3MgoqpGGLF2GnjGxynjY9DvJ58uJAz1CwXkIiKPo7rMYQPJLVCaQy3qtou8pYP4S8tr4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721060008; c=relaxed/simple; bh=uFG7cks4+8rIYWcWkztdf5fexMFjSjhJlAj9WO/mMcQ=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=jnUdVOXksz52QrJqvytztp0W6oC9KncxGZQN0HA7f9ebt8LMzc4MCtEBWuPGyOXsn3ubxZk5pbtvag/FlTIGYSyTsSi0Olrm+RKmbYox8BZ/DU/Jz7U41VZjgMBTkEtUPrj60D8u0Dg1o/TJYB66cvpK+THdjQA1LgVA3gJDhkc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=T4LA6Xlj; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="T4LA6Xlj" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1721060005; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=eMQDoOvPaudwg87cd/MCmAjG7MuyuOwLJH3IIe8WBJ8=; b=T4LA6XljcIXZiZThIh1MNrmPv9beR7lPxlk3Gck9vwmo6H1iiAop5Z04wSqFMYA1Jvpm74 k0206MduEs81i5fJKSs/3eiw8IZmD6QfgCF6CeIZIKyfMDq+yZySDC7lRG/Q2q8YGJ8ThV Vxl9BnDhq2y+DCoGSUaxmFqNshwpXjk= Received: from mail-wm1-f69.google.com (mail-wm1-f69.google.com [209.85.128.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-93-IyY05gfDO2WY5B62nKYYRw-1; Mon, 15 Jul 2024 12:13:24 -0400 X-MC-Unique: IyY05gfDO2WY5B62nKYYRw-1 Received: by mail-wm1-f69.google.com with SMTP id 5b1f17b1804b1-426d0bead0aso33385975e9.1 for ; Mon, 15 Jul 2024 09:13:23 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1721060003; x=1721664803; h=content-transfer-encoding:in-reply-to:organization:autocrypt :content-language:from:references:cc:to:subject:user-agent :mime-version:date:message-id:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to; bh=eMQDoOvPaudwg87cd/MCmAjG7MuyuOwLJH3IIe8WBJ8=; b=PGZH3IqTG0iYi6wfH2DX85sX6FUZXa5qP6sJYz7eitY7p5tspfLcFKEYt6VPZCh+Ij VjNM8BvDcUBbQdpWKvCobJCnGeZyeSHMZhoIO9y2FkILp4yMiKJd0UcBxP99UXNLrucx ytGOKHEF1VPEmM+/bdvB7+UO7V4lwlEoRQrvryZxb/iH7zC//wAxsJ8zm03VLCS7RHcE iJ5Uc6eyeD3s+r+W85cFbxyFiuS49G2pusFk1tbChk7voHZKSnGypd44MJl3v37eJzhV XtLO7/Xmc7KmKNsAMX2AGqCYqSvGbyn/cVLc45iBapARwAhCoATjHmbmd3R4RYfW3MuK WBbQ== X-Gm-Message-State: AOJu0Yyxnx67RGSZOu0m2guWqYvPD8A/G3SGT0TPSCYOdbA7aMC3vui7 PbXle6l5vHU7muWGCmAXoxAzkRCXnorkmeoOA3hEU7nO7jmCK3hD82jfqcL9m+VMid5hMdWvt8w c9D8wm2Wsz5OO7uc1HllV/Cm0vN/FggqgQYhtV9G3o1otw+UqruaORmjtrt7wPQ== X-Received: by 2002:a05:600c:524a:b0:426:6f27:379a with SMTP id 5b1f17b1804b1-427b8891044mr919625e9.13.1721060002985; Mon, 15 Jul 2024 09:13:22 -0700 (PDT) X-Google-Smtp-Source: AGHT+IGQjwYkzdJSfx95XkYjFANBsRchdvLjh8+4GPYb9A3EiFNIrWgmU1j6VXyHmDh6mAZ9Fu7Hrw== X-Received: by 2002:a05:600c:524a:b0:426:6f27:379a with SMTP id 5b1f17b1804b1-427b8891044mr919485e9.13.1721060002622; Mon, 15 Jul 2024 09:13:22 -0700 (PDT) Received: from [10.0.229.2] (ip-037-024-227-121.um08.pools.vodafone-ip.de. [37.24.227.121]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4279f2d6ef8sm126339895e9.39.2024.07.15.09.13.21 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 15 Jul 2024 09:13:22 -0700 (PDT) Message-ID: <2c3a5213-ca64-48fb-845a-78aae3e8f15f@redhat.com> Date: Mon, 15 Jul 2024 18:13:21 +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/huge_memory: Avoid PMD-size page cache if needed To: Ryan Roberts , Gavin Shan , linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org, willy@infradead.org, baohua@kernel.org, peterx@redhat.com, ziy@nvidia.com, william.kucharski@oracle.com, baolin.wang@linux.alibaba.com, ddutile@redhat.com, shan.gavin@gmail.com References: <20240715000423.316491-1-gshan@redhat.com> From: David Hildenbrand Content-Language: en-US Autocrypt: addr=david@redhat.com; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZgEEwEIAEICGwMGCwkIBwMCBhUIAgkKCwQW AgMBAh4BAheAAhkBFiEEG9nKrXNcTDpGDfzKTd4Q9wD/g1oFAl8Ox4kFCRKpKXgACgkQTd4Q 9wD/g1oHcA//a6Tj7SBNjFNM1iNhWUo1lxAja0lpSodSnB2g4FCZ4R61SBR4l/psBL73xktp rDHrx4aSpwkRP6Epu6mLvhlfjmkRG4OynJ5HG1gfv7RJJfnUdUM1z5kdS8JBrOhMJS2c/gPf wv1TGRq2XdMPnfY2o0CxRqpcLkx4vBODvJGl2mQyJF/gPepdDfcT8/PY9BJ7FL6Hrq1gnAo4 3Iv9qV0JiT2wmZciNyYQhmA1V6dyTRiQ4YAc31zOo2IM+xisPzeSHgw3ONY/XhYvfZ9r7W1l pNQdc2G+o4Di9NPFHQQhDw3YTRR1opJaTlRDzxYxzU6ZnUUBghxt9cwUWTpfCktkMZiPSDGd KgQBjnweV2jw9UOTxjb4LXqDjmSNkjDdQUOU69jGMUXgihvo4zhYcMX8F5gWdRtMR7DzW/YE BgVcyxNkMIXoY1aYj6npHYiNQesQlqjU6azjbH70/SXKM5tNRplgW8TNprMDuntdvV9wNkFs 9TyM02V5aWxFfI42+aivc4KEw69SE9KXwC7FSf5wXzuTot97N9Phj/Z3+jx443jo2NR34XgF 89cct7wJMjOF7bBefo0fPPZQuIma0Zym71cP61OP/i11ahNye6HGKfxGCOcs5wW9kRQEk8P9 M/k2wt3mt/fCQnuP/mWutNPt95w9wSsUyATLmtNrwccz63XOwU0EVcufkQEQAOfX3n0g0fZz Bgm/S2zF/kxQKCEKP8ID+Vz8sy2GpDvveBq4H2Y34XWsT1zLJdvqPI4af4ZSMxuerWjXbVWb T6d4odQIG0fKx4F8NccDqbgHeZRNajXeeJ3R7gAzvWvQNLz4piHrO/B4tf8svmRBL0ZB5P5A 2uhdwLU3NZuK22zpNn4is87BPWF8HhY0L5fafgDMOqnf4guJVJPYNPhUFzXUbPqOKOkL8ojk CXxkOFHAbjstSK5Ca3fKquY3rdX3DNo+EL7FvAiw1mUtS+5GeYE+RMnDCsVFm/C7kY8c2d0G NWkB9pJM5+mnIoFNxy7YBcldYATVeOHoY4LyaUWNnAvFYWp08dHWfZo9WCiJMuTfgtH9tc75 7QanMVdPt6fDK8UUXIBLQ2TWr/sQKE9xtFuEmoQGlE1l6bGaDnnMLcYu+Asp3kDT0w4zYGsx 5r6XQVRH4+5N6eHZiaeYtFOujp5n+pjBaQK7wUUjDilPQ5QMzIuCL4YjVoylWiBNknvQWBXS lQCWmavOT9sttGQXdPCC5ynI+1ymZC1ORZKANLnRAb0NH/UCzcsstw2TAkFnMEbo9Zu9w7Kv AxBQXWeXhJI9XQssfrf4Gusdqx8nPEpfOqCtbbwJMATbHyqLt7/oz/5deGuwxgb65pWIzufa N7eop7uh+6bezi+rugUI+w6DABEBAAHCwXwEGAEIACYCGwwWIQQb2cqtc1xMOkYN/MpN3hD3 AP+DWgUCXw7HsgUJEqkpoQAKCRBN3hD3AP+DWrrpD/4qS3dyVRxDcDHIlmguXjC1Q5tZTwNB boaBTPHSy/Nksu0eY7x6HfQJ3xajVH32Ms6t1trDQmPx2iP5+7iDsb7OKAb5eOS8h+BEBDeq 3ecsQDv0fFJOA9ag5O3LLNk+3x3q7e0uo06XMaY7UHS341ozXUUI7wC7iKfoUTv03iO9El5f XpNMx/YrIMduZ2+nd9Di7o5+KIwlb2mAB9sTNHdMrXesX8eBL6T9b+MZJk+mZuPxKNVfEQMQ a5SxUEADIPQTPNvBewdeI80yeOCrN+Zzwy/Mrx9EPeu59Y5vSJOx/z6OUImD/GhX7Xvkt3kq Er5KTrJz3++B6SH9pum9PuoE/k+nntJkNMmQpR4MCBaV/J9gIOPGodDKnjdng+mXliF3Ptu6 3oxc2RCyGzTlxyMwuc2U5Q7KtUNTdDe8T0uE+9b8BLMVQDDfJjqY0VVqSUwImzTDLX9S4g/8 kC4HRcclk8hpyhY2jKGluZO0awwTIMgVEzmTyBphDg/Gx7dZU1Xf8HFuE+UZ5UDHDTnwgv7E th6RC9+WrhDNspZ9fJjKWRbveQgUFCpe1sa77LAw+XFrKmBHXp9ZVIe90RMe2tRL06BGiRZr jPrnvUsUUsjRoRNJjKKA/REq+sAnhkNPPZ/NNMjaZ5b8Tovi8C0tmxiCHaQYqj7G2rgnT0kt WNyWQQ== Organization: Red Hat In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 15.07.24 12:41, Ryan Roberts wrote: > [...] > >> diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h >> index 2aa986a5cd1b..c73ad77fa33d 100644 >> --- a/include/linux/huge_mm.h >> +++ b/include/linux/huge_mm.h >> @@ -72,14 +72,20 @@ extern struct kobj_attribute shmem_enabled_attr; >> #define THP_ORDERS_ALL_ANON ((BIT(PMD_ORDER + 1) - 1) & ~(BIT(0) | BIT(1))) >> >> /* >> - * Mask of all large folio orders supported for file THP. >> + * Mask of all large folio orders supported for file THP. Folios in a DAX >> + * file is never split and the MAX_PAGECACHE_ORDER limit does not apply to >> + * it. >> */ >> -#define THP_ORDERS_ALL_FILE (BIT(PMD_ORDER) | BIT(PUD_ORDER)) >> +#define THP_ORDERS_ALL_FILE_DAX \ >> + (BIT(PMD_ORDER) | BIT(PUD_ORDER)) > > Appologies if this was already discussed, but if changing _FILE_DEFAULT to > advertise all orders 1-MAX_PAGECACHE_ORDER, shouldn't we also change _FILE_DAX > to advertise all orders 1-PUD_ORDER ? Or is DAX literally limited to PTE/PMD/PUD? It's limited to that. IIUC, it's simply some physical memory area that can be interpreted as small folios, PMD-sized folios or PUD-sized folios, and someone (fsdax?) makes the decision "how" it is interpreted/setup these folios. These folios can only be mapped entirely (single PMD/PUD) or via PTEs, so PMD_ORDER+PUD_ORDER is correct. Thanks Gavin! Acked-by: David Hildenbrand -- Cheers, David / dhildenb