From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 A08662EA72F for ; Fri, 4 Jul 2025 10:24:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751624649; cv=none; b=fy25Qup0lGLvRdt2WD5BFJ/8tq5xM6i5H028epAzBh8bmcl39WOZMRex1O9QYA9dKfXRrB0splNvKLpEKrOqQxEhheZ3DnvwEeY96+scxa9Xq4lXLSzXuzI8q/6e+xJzUjj1KA/FayPZAul10s6vqIVLMOKUASNRvSoW8w9VHhI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751624649; c=relaxed/simple; bh=ZJwUzCRTgCIwdT0O3a29QA8yJr7c2jadRe+FBqGr2yc=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=cTEKGhLuYWn9jgS666mZjcdUbuL5de06eA3Tqb/JS4btoItDE9l9wG1Mz9kD004DUjs0QIeshvY2+S/yDVKwcQII080d6MpqEkHnlsdFqMYlgy4XvbpDhdWJaURnzWnNiu9KeggPoKiiWbgZERlL+aPDtEWrDzLWledWjNoo2EA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine 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=Rjue7v6E; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine 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="Rjue7v6E" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1751624646; 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=7AHt5Z64vpLLNCpfL1vnLoZ56sFLeXdpOw9WEu1NFok=; b=Rjue7v6EMIqI1j0jkXtTS0V8oNiH+WUiP+u5CeMvCdPdfxw8Chm3xCaObn0u3OcgZXhPAc 8BfHkGPBz3JtItAPaC5ZvFjngQvCXoAAYcSznDeWMycWrg6ItYJm44/zn6ZeRi+sv5YQcY 7KDS+iVE2hsGAkUvhispJlZPKhm3lcM= Received: from mail-wm1-f72.google.com (mail-wm1-f72.google.com [209.85.128.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-540-MbIdq8TLP9-mVOH4H4Bjww-1; Fri, 04 Jul 2025 06:24:05 -0400 X-MC-Unique: MbIdq8TLP9-mVOH4H4Bjww-1 X-Mimecast-MFC-AGG-ID: MbIdq8TLP9-mVOH4H4Bjww_1751624644 Received: by mail-wm1-f72.google.com with SMTP id 5b1f17b1804b1-450d290d542so4565425e9.1 for ; Fri, 04 Jul 2025 03:24:04 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1751624644; x=1752229444; 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=7AHt5Z64vpLLNCpfL1vnLoZ56sFLeXdpOw9WEu1NFok=; b=RuANISO3Cb5yMmFf9mG5/e0FLMhTTdYW4yvj5zdtTq6ZiK2kvlt6IIraYqHExfBjIU gGv1Ff7CxjHyuEvPF6e1BkIB+wJjntZP0vQInp00INUaNaS+DtKYmUC93yzgKTuGaCGU iIyadescsDurPN+PB+S3tYT5OeOPXp8xmuoH1ATuQks8gq6FF62MroF27ueqm3njhb0Y v8ParE1kmnYG2Zv6dYJ3cwoMpkKL5VSofBRIHCqpm/Dw26iFHKUgM+5R9qKKySkBXIR8 qeqHuY3/hqx5OxqXEfmFGlCX4LGeZWGrD1kVNTa10j51jbI9umfb/985jwAkL8KMpeqj 4qhg== X-Gm-Message-State: AOJu0YxH5WxARYh9dyBk5ymVRUuP8ziyydIqxB8AJYBIa4/RNAQk5Qc7 r23zhy46XLSEi+7ELWVUNc5PpBf/4WubgLJ/V5qPbF8L/UuBSbhXMUV6OsF/WoU0XN1vdturJra sg9RDkAs3T0+85U2YRxSZmsv42WkAQV2tptO0vCmTTYyd1g91EsoIvkAiD/km6weQ9XPBZDUrvJ 4= X-Gm-Gg: ASbGncuZFGzxGlAsyiwGe2Fo/AVa4Zv61wc492yEiVTI7JMgqsaet7245nVpsMAmA8r 8eW8+sDUkvG6TobVAd/5bchYK2u2VBbsQg0R2aCJntc0p2ALKH8VT0GFUuWtgqXkE8ZOx1uJgzr BRdrJqHF09o09btZ3lqZXxrEJm+iR0SBkgsqQaQXUfSsRP6VEoYZErJwVeSta5O6Rtb/YgmBG7H mPpupKzCbAOcelycOP7wQRnLG2GeEgO5VKx1r5i2RWMW55NkcHPDvWEpLukzd3gYk053d4Nb67h S1G1s5kqNl23p6lYAdObCaViJQlBz5LDXVnTmZRoCH0840GVL/l3kbtgmpl+KJNawfrevwufztb V85KHfsHTKpe+i/aJ9E9rEIMAP7ZlncLNSsnxw6UWxiaQBfk= X-Received: by 2002:a05:6000:2285:b0:3aa:c95b:d1d9 with SMTP id ffacd0b85a97d-3b4964eb200mr1425057f8f.6.1751624643790; Fri, 04 Jul 2025 03:24:03 -0700 (PDT) X-Google-Smtp-Source: AGHT+IE4A0/1h/B1ilYGbTmBY8ZH5/8hdcvdonFBLczJBmXXW5tX2H5RoW9cZXDpBaGbEcNzqAXTog== X-Received: by 2002:a05:6000:2285:b0:3aa:c95b:d1d9 with SMTP id ffacd0b85a97d-3b4964eb200mr1425028f8f.6.1751624643334; Fri, 04 Jul 2025 03:24:03 -0700 (PDT) Received: from ?IPV6:2003:d8:2f2c:5500:988:23f9:faa0:7232? (p200300d82f2c5500098823f9faa07232.dip0.t-ipconnect.de. [2003:d8:2f2c:5500:988:23f9:faa0:7232]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3b47030ba29sm2100881f8f.2.2025.07.04.03.24.02 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 04 Jul 2025 03:24:02 -0700 (PDT) Message-ID: <6d9c08dd-c1d0-48bd-aacb-b4300f87d525@redhat.com> Date: Fri, 4 Jul 2025 12:24:01 +0200 Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 10/11] fuse: optimize direct io large folios processing To: Joanne Koong , miklos@szeredi.hu Cc: linux-fsdevel@vger.kernel.org, jlayton@kernel.org, jefflexu@linux.alibaba.com, josef@toxicpanda.com, bernd.schubert@fastmail.fm, willy@infradead.org, kernel-team@meta.com References: <20250426000828.3216220-1-joannelkoong@gmail.com> <20250426000828.3216220-11-joannelkoong@gmail.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: <20250426000828.3216220-11-joannelkoong@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 26.04.25 02:08, Joanne Koong wrote: > Optimize processing folios larger than one page size for the direct io > case. If contiguous pages are part of the same folio, collate the > processing instead of processing each page in the folio separately. > > Signed-off-by: Joanne Koong > Reviewed-by: Jeff Layton > --- > fs/fuse/file.c | 55 +++++++++++++++++++++++++++++++++++++------------- > 1 file changed, 41 insertions(+), 14 deletions(-) > > diff --git a/fs/fuse/file.c b/fs/fuse/file.c > index 9a31f2a516b9..61eaec1c993b 100644 > --- a/fs/fuse/file.c > +++ b/fs/fuse/file.c > @@ -1490,7 +1490,8 @@ static int fuse_get_user_pages(struct fuse_args_pages *ap, struct iov_iter *ii, > } > > while (nbytes < *nbytesp && nr_pages < max_pages) { > - unsigned nfolios, i; > + struct folio *prev_folio = NULL; > + unsigned npages, i; > size_t start; > > ret = iov_iter_extract_pages(ii, &pages, > @@ -1502,23 +1503,49 @@ static int fuse_get_user_pages(struct fuse_args_pages *ap, struct iov_iter *ii, > > nbytes += ret; > > - nfolios = DIV_ROUND_UP(ret + start, PAGE_SIZE); > + npages = DIV_ROUND_UP(ret + start, PAGE_SIZE); > > - for (i = 0; i < nfolios; i++) { > - struct folio *folio = page_folio(pages[i]); > - unsigned int offset = start + > - (folio_page_idx(folio, pages[i]) << PAGE_SHIFT); > - unsigned int len = min_t(unsigned int, ret, PAGE_SIZE - start); > + /* > + * We must check each extracted page. We can't assume every page > + * in a large folio is used. For example, userspace may mmap() a > + * file PROT_WRITE, MAP_PRIVATE, and then store to the middle of > + * a large folio, in which case the extracted pages could be > + * > + * folio A page 0 > + * folio A page 1 > + * folio B page 0 > + * folio A page 3 > + * > + * where folio A belongs to the file and folio B is an anonymous > + * COW page. > + */ > + for (i = 0; i < npages && ret; i++) { > + struct folio *folio; > + unsigned int offset; > + unsigned int len; > + > + WARN_ON(!pages[i]); > + folio = page_folio(pages[i]); > + > + len = min_t(unsigned int, ret, PAGE_SIZE - start); > + > + if (folio == prev_folio && pages[i] != pages[i - 1]) { I don't really understand the "pages[i] != pages[i - 1]" part. Why would you have to equal page pointers in there? Something that might be simpler to understand and implement would be using num_pages_contiguous() from https://lore.kernel.org/all/20250704062602.33500-2-lizhe.67@bytedance.com/T/#u and then just making sure that we don't exceed the current folio, if we ever get contiguous pages that cross a folio. -- Cheers, David / dhildenb