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([2a09:80c0:192:0:5dac:bf3d:c41:c3e7]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-42bb6deb1ebsm138607655e9.3.2024.09.02.06.45.04 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 02 Sep 2024 06:45:04 -0700 (PDT) Message-ID: <3b8994a6-cbe5-46be-86eb-b78198c31ef8@redhat.com> Date: Mon, 2 Sep 2024 15:45:03 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] mm: Skip the reserved bootmem for compaction To: Rong Qianfeng , vbabka@suse.cz, mgorman@techsingularity.net, Andrew Morton , Mike Rapoport , "Kirill A. Shutemov" , Zi Yan , Baolin Wang , linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: opensource.kernel@vivo.com References: <20240902122445.11805-1-rongqianfeng@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: <20240902122445.11805-1-rongqianfeng@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-Server: rspam03 X-Rspam-User: X-Rspamd-Queue-Id: 94248C0017 X-Stat-Signature: g4xtf4z4ztbu6xqz7a3s9oyu8pc1ia5n X-HE-Tag: 1725284709-970642 X-HE-Meta: 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 ++6iF7jB s0Ed73AFh4jzQmEYr95ua7epBpvRezhv8/NEV8JePtWyNX+/+t2TtWB5dZZ1O0RC+vWywnZroKTSmgW6fDlTw3/L5thbYbpozUo9li3YgiAkBdgEi+5tAlDcJKV1Arpegn/ZMk4SH30Zq/VkFwZQunGQosL/lFlBiFNLzNFGKDy3B9kBMSx5OqJmeWojGBW97C6nuILDddYgkqJAu95kvhRKbL9G9lAj81N2AJlDwdo4FdtowOZ8ey0bHqPqgvQF5UuAu+ZvslpvQOk2bCyNz7eRNTZYqJW5G8vi3CXLS+gk7Ft/6J7iCgHVrbzkLTOIgfn4HNqJ5nf9LFiINVr6iZ0H9Ck0EyGdksTrEVWJrD+cAAMhm8rEWW1MRoss7p8vnkbBTYhNrd97Vb2XbXecKFRsZK0VbxTR7T1GPhjzovz2OE5HLZvVRL2LfUJ8bbZYz3c68fp8ExvEviTkTFVDK7xrbNOBl/GPhVQw2 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 02.09.24 14:24, Rong Qianfeng wrote: > Reserved pages are basically non-lru pages. This kind of memory can't be > used as migration sources and targets, skip it can bring some performance > benefits. Any numbers? :) > > Because some drivers may also use PG_reserved, we just set PB_migrate_skip > for those clustered reserved bootmem during memory initialization. > > Signed-off-by: Rong Qianfeng > --- > include/linux/pageblock-flags.h | 13 +++++++++++ > mm/compaction.c | 40 +++++++++++++++++++++++++++++++++ > mm/mm_init.c | 14 ++++++++++++ > mm/page_alloc.c | 7 ++++++ > 4 files changed, 74 insertions(+) > > diff --git a/include/linux/pageblock-flags.h b/include/linux/pageblock-flags.h > index fc6b9c87cb0a..63c5b0c69c1a 100644 > --- a/include/linux/pageblock-flags.h > +++ b/include/linux/pageblock-flags.h > @@ -86,6 +86,11 @@ void set_pfnblock_flags_mask(struct page *page, > set_pfnblock_flags_mask(page, (1 << PB_migrate_skip), \ > page_to_pfn(page), \ > (1 << PB_migrate_skip)) > + > +extern void set_pageblock_skip_range(unsigned long start_pfn, > + unsigned long end_pfn); two tabs indentation on the second line please. Applies to all others as well. > +extern void clear_pageblock_skip_range(unsigned long start_pfn, > + unsigned long end_pfn); > #else > static inline bool get_pageblock_skip(struct page *page) > { > @@ -97,6 +102,14 @@ static inline void clear_pageblock_skip(struct page *page) > static inline void set_pageblock_skip(struct page *page) > { > } > +static inline void set_pageblock_skip_range(unsigned long start_pfn, > + unsigned long end_pfn) > +{ > +} > +static inline void clear_pageblock_skip_range(unsigned long start_pfn, > + unsigned long end_pfn) > +{ > +} [...] > /* > * Compound pages of >= pageblock_order should consistently be skipped until > * released. It is always pointless to compact pages of such order (if they are > diff --git a/mm/mm_init.c b/mm/mm_init.c > index 4ba5607aaf19..8b7dc8e00bf1 100644 > --- a/mm/mm_init.c > +++ b/mm/mm_init.c > @@ -768,6 +768,13 @@ void __meminit reserve_bootmem_region(phys_addr_t start, > __SetPageReserved(page); > } > } > + > + /* > + * Set PB_migrate_skip for reserved region. for cma memory > + * and the memory released by free_reserved_area(), we will > + * clear PB_migrate_skip when they are initialized. > + */ > + set_pageblock_skip_range(start_pfn, end_pfn); > } > > /* If zone is ZONE_MOVABLE but memory is mirrored, it is an overlapped init */ > @@ -2236,6 +2243,13 @@ void __init init_cma_reserved_pageblock(struct page *page) > set_page_count(p, 0); > } while (++p, --i); > > + /* > + * We set the PB_migrate_skip in > + * reserve_bootmem_region() for cma > + * memory, clear it now. You can fit this easily into less lines > + */ > + clear_pageblock_skip(page); > + > set_pageblock_migratetype(page, MIGRATE_CMA); > set_page_refcounted(page); > /* pages were reserved and not allocated */ > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index b98f9bb28234..a7729dac0198 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -5887,6 +5887,13 @@ unsigned long free_reserved_area(void *start, void *end, int poison, const char > if (pages && s) > pr_info("Freeing %s memory: %ldK\n", s, K(pages)); > > + /* > + * Clear PB_migrate_skip if the memory have released > + * to the buddy system. > + */ ... after freeing the memory to the buddy." And maybe if (pages) { if (s) pr_info("Freeing %s memory: %ldK\n", s, K(pages)); clear_pageblock_skip_range(...) } > + clear_pageblock_skip_range(page_to_pfn(virt_to_page(start)), > + page_to_pfn(virt_to_page(end))); > + PHYS_PFN(virt_to_phys(start)) might look a bit nicer, not need to get pages involved. virt_to_pfn might be even better(), but it's not available on all archs I think. What about free_reserved_page() ? There might be more, though (kimage_free_pages()). You have to take a look at all functions where we clear PageReserved. -- Cheers, David / dhildenb