From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 19566C67861 for ; Fri, 5 Apr 2024 09:24:45 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 979C36B0133; Fri, 5 Apr 2024 05:24:44 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9039D6B0135; Fri, 5 Apr 2024 05:24:44 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7556E6B0136; Fri, 5 Apr 2024 05:24:44 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 5415A6B0133 for ; Fri, 5 Apr 2024 05:24:44 -0400 (EDT) Received: from smtpin20.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id CCD34810B7 for ; Fri, 5 Apr 2024 09:24:43 +0000 (UTC) X-FDA: 81974943246.20.33BF7D8 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by imf22.hostedemail.com (Postfix) with ESMTP id 8C0E7C000B for ; Fri, 5 Apr 2024 09:24:41 +0000 (UTC) Authentication-Results: imf22.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=Tt5IrNLv; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf22.hostedemail.com: domain of david@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=david@redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1712309081; h=from:from:sender: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:dkim-signature; bh=5CUGEh7qt513XXq70meozxW0RhRyZE2IyjxQxM/2VZo=; b=iaP2Gwi157IwjCZedFR3kxFsQFOqi39oFc6insKXANMw9SSZBoSt+haj5xW/ULZzx4IYVX gZ60k/KqbaH4CLGA0LxMn++lLZ+WkzHJf6V2dcNEO/BMaWvHk2WcIABBSJV0wRtV+nLP6z BrRJ2JDz45DhRf2AaADdlJJHLxaphUM= ARC-Authentication-Results: i=1; imf22.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=Tt5IrNLv; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf22.hostedemail.com: domain of david@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=david@redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1712309081; a=rsa-sha256; cv=none; b=e3EtW5CizpimEtjr+rRbnXwUfaQINHb5a3js6QH5/kLDYJMsMmIWPL7xU6U2FIBdXqvjEE G26CQtiC7TXSyQaPayrkha590Q/tkQlTTkTcSReQSXvZ+2M7krPaGv+SomzMbm4sw/QlId XIelxkIkB/d8BL+WbS1P7njlBZWBkvc= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1712309080; 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=5CUGEh7qt513XXq70meozxW0RhRyZE2IyjxQxM/2VZo=; b=Tt5IrNLvpRFjYMGB1cdNr/K3pEVEQUJep9NHXuD6GNLsQCCMSBFcFqQ9IGeU5uRjmM5VtU w+34Nf1Ewvl8crw6dOqkhbRKkC/FvkZWl4kmYTNeXkdrfVtlp4/ApamAT5uSI/G2/QUlbL k+IwoOYkDGgA3vBBe57OtS2vXjLl9iU= Received: from mail-wr1-f72.google.com (mail-wr1-f72.google.com [209.85.221.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-651-PjON4v7IMI29s0KR429OmQ-1; Fri, 05 Apr 2024 05:24:39 -0400 X-MC-Unique: PjON4v7IMI29s0KR429OmQ-1 Received: by mail-wr1-f72.google.com with SMTP id ffacd0b85a97d-343678d2d26so1026145f8f.0 for ; Fri, 05 Apr 2024 02:24:39 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1712309078; x=1712913878; h=content-transfer-encoding:in-reply-to:organization:autocrypt:from :content-language: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=5CUGEh7qt513XXq70meozxW0RhRyZE2IyjxQxM/2VZo=; b=m6jpInvPRRVGq+RAfR3Zis5jCtUf4WeBSWEsfJRe6zTKnZKpnLhi/11rbWc9l+uvyc zCRYkntTNzixBxQ+lxtZ3/0gYnej1Atq1+3J8F+6ztGquwMf16Uyxw+858LgEtX+JFNb dVTJxNSXrNs+MBj7E738ZuduUFczDcCBvOUH2KMPHskJXBgCYUVYPAydUztDd/WrwO1H HGf92nPOs39jiheDZLjUdwE9ZXL0TJ0Orhmb4Dp0wCxASl7jruZs5N9RAusg9NXrOkla 0RneHbGCwhRWh0wdxc0avqLWUhtUDkfNUuYl3OW1Z/ADkVUW/qPhRFw7JGzF0XeMcUsH wbNw== X-Forwarded-Encrypted: i=1; AJvYcCXkTxGg4pAYRuFiNefHQq3YeK2f/sKmrAT/FlTOTOgjm5yCNL6K93VhbzbZp1ureqOTUBBFzKUUVuREvALK4z0Y8vg= X-Gm-Message-State: AOJu0Yx9rRMZ1emXh831PpjCX6laj90HErkoqrJhcgep9/Nxsis8QiPj 9mnoqqr081cWBn9h2MqLvhR8bQEmhnng5odC1vq35js4/Eo7cDPsUxuWHr85J33QON447dYin6Z Wh9ar4k5aRfPlk8idds1RCWYwX9aPIuFooT4icKi2tEDeNQml X-Received: by 2002:adf:e9c4:0:b0:343:dde1:2ef6 with SMTP id l4-20020adfe9c4000000b00343dde12ef6mr1522658wrn.27.1712309078246; Fri, 05 Apr 2024 02:24:38 -0700 (PDT) X-Google-Smtp-Source: AGHT+IETvnnYUTERDtD8QL5p05wSwIy4I+fVaePwiqrjA6gbsbZPJlrr5CFHgaERteBP0qlfc0HVgg== X-Received: by 2002:adf:e9c4:0:b0:343:dde1:2ef6 with SMTP id l4-20020adfe9c4000000b00343dde12ef6mr1522634wrn.27.1712309077765; Fri, 05 Apr 2024 02:24:37 -0700 (PDT) Received: from ?IPV6:2003:cb:c74b:5500:e1f8:a310:8fa3:4ec1? (p200300cbc74b5500e1f8a3108fa34ec1.dip0.t-ipconnect.de. [2003:cb:c74b:5500:e1f8:a310:8fa3:4ec1]) by smtp.gmail.com with ESMTPSA id f11-20020a5d568b000000b00343c9ce4b50sm1559079wrv.53.2024.04.05.02.24.36 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 05 Apr 2024 02:24:37 -0700 (PDT) Message-ID: <7d5b2f03-dc36-477d-8d5c-4eb8d45db398@redhat.com> Date: Fri, 5 Apr 2024 11:24:36 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 2/6] mm: swap: free_swap_and_cache_nr() as batched free_swap_and_cache() To: Ryan Roberts , Zi Yan Cc: Andrew Morton , Matthew Wilcox , Huang Ying , Gao Xiang , Yu Zhao , Yang Shi , Michal Hocko , Kefeng Wang , Barry Song <21cnbao@gmail.com>, Chris Li , Lance Yang , linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20240327144537.4165578-1-ryan.roberts@arm.com> <20240327144537.4165578-3-ryan.roberts@arm.com> <4020c532-d20d-4624-8ea6-607de423396c@arm.com> From: David Hildenbrand 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: <4020c532-d20d-4624-8ea6-607de423396c@arm.com> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Stat-Signature: w7fhrhp5erq6inx8y83m5h5e1971nbyn X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 8C0E7C000B X-HE-Tag: 1712309081-103036 X-HE-Meta: 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 P+JTJwFm 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 03.04.24 09:21, Ryan Roberts wrote: > On 03/04/2024 01:30, Zi Yan wrote: >> On 27 Mar 2024, at 10:45, Ryan Roberts wrote: >> >>> Now that we no longer have a convenient flag in the cluster to determine >>> if a folio is large, free_swap_and_cache() will take a reference and >>> lock a large folio much more often, which could lead to contention and >>> (e.g.) failure to split large folios, etc. >>> >>> Let's solve that problem by batch freeing swap and cache with a new >>> function, free_swap_and_cache_nr(), to free a contiguous range of swap >>> entries together. This allows us to first drop a reference to each swap >>> slot before we try to release the cache folio. This means we only try to >>> release the folio once, only taking the reference and lock once - much >>> better than the previous 512 times for the 2M THP case. >>> >>> Contiguous swap entries are gathered in zap_pte_range() and >>> madvise_free_pte_range() in a similar way to how present ptes are >>> already gathered in zap_pte_range(). >>> >>> While we are at it, let's simplify by converting the return type of both >>> functions to void. The return value was used only by zap_pte_range() to >>> print a bad pte, and was ignored by everyone else, so the extra >>> reporting wasn't exactly guaranteed. We will still get the warning with >>> most of the information from get_swap_device(). With the batch version, >>> we wouldn't know which pte was bad anyway so could print the wrong one. >>> >>> Signed-off-by: Ryan Roberts >>> --- >>> include/linux/pgtable.h | 28 +++++++++++++++ >>> include/linux/swap.h | 12 +++++-- >>> mm/internal.h | 48 +++++++++++++++++++++++++ >>> mm/madvise.c | 12 ++++--- >>> mm/memory.c | 13 +++---- >>> mm/swapfile.c | 78 ++++++++++++++++++++++++++++++----------- >>> 6 files changed, 157 insertions(+), 34 deletions(-) >>> >>> diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h >>> index 09c85c7bf9c2..8185939df1e8 100644 >>> --- a/include/linux/pgtable.h >>> +++ b/include/linux/pgtable.h >>> @@ -708,6 +708,34 @@ static inline void pte_clear_not_present_full(struct mm_struct *mm, >>> } >>> #endif >>> >>> +#ifndef clear_not_present_full_ptes >>> +/** >>> + * clear_not_present_full_ptes - Clear consecutive not present PTEs. >>> + * @mm: Address space the ptes represent. >>> + * @addr: Address of the first pte. >>> + * @ptep: Page table pointer for the first entry. >>> + * @nr: Number of entries to clear. >>> + * @full: Whether we are clearing a full mm. >>> + * >>> + * May be overridden by the architecture; otherwise, implemented as a simple >>> + * loop over pte_clear_not_present_full(). >>> + * >>> + * Context: The caller holds the page table lock. The PTEs are all not present. >>> + * The PTEs are all in the same PMD. >>> + */ >>> +static inline void clear_not_present_full_ptes(struct mm_struct *mm, >>> + unsigned long addr, pte_t *ptep, unsigned int nr, int full) >>> +{ >>> + for (;;) { >>> + pte_clear_not_present_full(mm, addr, ptep, full); >>> + if (--nr == 0) >>> + break; >>> + ptep++; >>> + addr += PAGE_SIZE; >>> + } >>> +} >>> +#endif >>> + >> >> Would the code below be better? >> >> for (i = 0; i < nr; i++, ptep++, addr += PAGE_SIZE) >> pte_clear_not_present_full(mm, addr, ptep, full); > > I certainly agree that this is cleaner and more standard. But I'm copying the > pattern used by the other batch helpers. I believe this pattern was first done > by Willy for set_ptes(), then continued by DavidH for wrprotect_ptes() and > clear_full_ptes(). > > I guess the benefit is that ptep and addr are only incremented if we are going > around the loop again. I'd rather continue to be consistent with those other > helpers. Yes please. I remember Willy found that variant to be most micro-optimized. -- Cheers, David / dhildenb