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[2003:cb:c70b:500:6a06:17fc:810b:b054]) by smtp.gmail.com with ESMTPSA id b17-20020a05600010d100b003197869bcd7sm4555315wrx.13.2023.10.19.07.15.09 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 19 Oct 2023 07:15:09 -0700 (PDT) Message-ID: <2d847d76-2e33-4296-992f-1a6d00c66ff5@redhat.com> Date: Thu, 19 Oct 2023 16:15:08 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 1/2] mm:vmscan: the dirty folio in folio_list skip unmap To: Zhiguo Jiang , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: opensource.kernel@vivo.com References: <20231019131446.317-1-justinjiang@vivo.com> <20231019131446.317-2-justinjiang@vivo.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: <20231019131446.317-2-justinjiang@vivo.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-Rspamd-Queue-Id: D53A7140025 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: 6r8cyqxdr4ah5c5i9agtckqijwoshqqn X-HE-Tag: 1697724913-776400 X-HE-Meta: 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 AkEgvsv7 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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: On 19.10.23 15:14, Zhiguo Jiang wrote: > In the shrink_folio_list() the sources of the file dirty folio include > two ways below: > 1. The dirty folio is from the incoming parameter folio_list, > which is the inactive file lru. > 2. The dirty folio is from the PTE dirty bit transferred by > the try_to_unmap(). > > For the first source of the dirty folio, if the dirty folio does not > support pageout, the dirty folio can skip unmap in advance to reduce > recyling time. > > Signed-off-by: Zhiguo Jiang > --- > > Changelog: > v1->v2: > 1. Keep the original judgment flow. > 2. Add the interface of folio_check_pageout(). > 3. The dirty folio which does not support pageout in inactive file lru > skip unmap in advance. > > mm/vmscan.c | 103 +++++++++++++++++++++++++++++++++------------------- > 1 file changed, 66 insertions(+), 37 deletions(-) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index a68d01fcc307..e067269275a5 100755 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -925,6 +925,44 @@ static void folio_check_dirty_writeback(struct folio *folio, > mapping->a_ops->is_dirty_writeback(folio, dirty, writeback); > } > > +/* Check if a dirty folio can support pageout in the recyling process*/ > +static bool folio_check_pageout(struct folio *folio, > + struct pglist_data *pgdat) > +{ > + int ret = true; > + > + /* > + * Anonymous folios are not handled by flushers and must be written > + * from reclaim context. Do not stall reclaim based on them. > + * MADV_FREE anonymous folios are put into inactive file list too. > + * They could be mistakenly treated as file lru. So further anon > + * test is needed. > + */ > + if (!folio_is_file_lru(folio) || > + (folio_test_anon(folio) && !folio_test_swapbacked(folio))) > + goto out; > + > + if (folio_test_dirty(folio) && > + (!current_is_kswapd() || > + !folio_test_reclaim(folio) || > + !test_bit(PGDAT_DIRTY, &pgdat->flags))) { > + /* > + * Immediately reclaim when written back. > + * Similar in principle to folio_deactivate() > + * except we already have the folio isolated > + * and know it's dirty > + */ > + node_stat_mod_folio(folio, NR_VMSCAN_IMMEDIATE, > + folio_nr_pages(folio)); > + folio_set_reclaim(folio); > + > + ret = false; > + } > + > +out: > + return ret; > +} > + > static struct folio *alloc_demote_folio(struct folio *src, > unsigned long private) > { > @@ -1078,6 +1116,12 @@ static unsigned int shrink_folio_list(struct list_head *folio_list, > if (dirty && !writeback) > stat->nr_unqueued_dirty += nr_pages; > > + /* If the dirty folio dose not support pageout, > + * the dirty folio can skip this recycling. > + */ > + if (!folio_check_pageout(folio, pgdat)) > + goto activate_locked; > + > /* > * Treat this folio as congested if folios are cycling > * through the LRU so quickly that the folios marked > @@ -1261,43 +1305,6 @@ static unsigned int shrink_folio_list(struct list_head *folio_list, > enum ttu_flags flags = TTU_BATCH_FLUSH; > bool was_swapbacked = folio_test_swapbacked(folio); > > - if (folio_test_dirty(folio)) { > - /* > - * Only kswapd can writeback filesystem folios > - * to avoid risk of stack overflow. But avoid > - * injecting inefficient single-folio I/O into > - * flusher writeback as much as possible: only > - * write folios when we've encountered many > - * dirty folios, and when we've already scanned > - * the rest of the LRU for clean folios and see > - * the same dirty folios again (with the reclaim > - * flag set). > - */ > - if (folio_is_file_lru(folio) && > - (!current_is_kswapd() || > - !folio_test_reclaim(folio) || > - !test_bit(PGDAT_DIRTY, &pgdat->flags))) { > - /* > - * Immediately reclaim when written back. > - * Similar in principle to folio_deactivate() > - * except we already have the folio isolated > - * and know it's dirty > - */ > - node_stat_mod_folio(folio, NR_VMSCAN_IMMEDIATE, > - nr_pages); > - folio_set_reclaim(folio); > - > - goto activate_locked; > - } > - > - if (references == FOLIOREF_RECLAIM_CLEAN) > - goto keep_locked; > - if (!may_enter_fs(folio, sc->gfp_mask)) > - goto keep_locked; > - if (!sc->may_writepage) > - goto keep_locked; > - } > - > if (folio_test_pmd_mappable(folio)) > flags |= TTU_SPLIT_HUGE_PMD; > > @@ -1323,6 +1330,28 @@ static unsigned int shrink_folio_list(struct list_head *folio_list, > > mapping = folio_mapping(folio); > if (folio_test_dirty(folio)) { > + /* > + * Only kswapd can writeback filesystem folios > + * to avoid risk of stack overflow. But avoid > + * injecting inefficient single-folio I/O into > + * flusher writeback as much as possible: only > + * write folios when we've encountered many > + * dirty folios, and when we've already scanned > + * the rest of the LRU for clean folios and see > + * the same dirty folios again (with the reclaim > + * flag set). > + */ > + if (folio_is_file_lru(folio) && > + !folio_check_pageout(folio, pgdat)) > + goto activate_locked; > + > + if (references == FOLIOREF_RECLAIM_CLEAN) > + goto keep_locked; > + if (!may_enter_fs(folio, sc->gfp_mask)) > + goto keep_locked; > + if (!sc->may_writepage) > + goto keep_locked; > + > /* > * Folio is dirty. Flush the TLB if a writable entry > * potentially exists to avoid CPU writes after I/O I'm confused. Did you apply this on top of v1 by accident? -- Cheers, David / dhildenb