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[2003:d8:2f09:3f00:d228:bd67:7baa:d604]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4290c77f078sm238744585e9.37.2024.08.13.09.13.02 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 13 Aug 2024 09:13:02 -0700 (PDT) Message-ID: <3c227f55-613b-4acf-a6e4-b054c8b54277@redhat.com> Date: Tue, 13 Aug 2024 18:13:01 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3] mm: Override mTHP "enabled" defaults at kernel cmdline To: Barry Song <21cnbao@gmail.com>, akpm@linux-foundation.org, linux-mm@kvack.org Cc: ryan.roberts@arm.com, baohua@kernel.org, baolin.wang@linux.alibaba.com, corbet@lwn.net, ioworker0@gmail.com, linux-kernel@vger.kernel.org, Barry Song References: <20240812102445.162087-1-21cnbao@gmail.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: <20240812102445.162087-1-21cnbao@gmail.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-Rspamd-Queue-Id: E7D6810000B X-Rspamd-Server: rspam01 X-Stat-Signature: y8bzegcknqgcm3xurr5i1n7ajnyrr3zf X-HE-Tag: 1723565586-563481 X-HE-Meta: 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 Z3LwbO7o zrVUEQ8rq2MgZlzU0dSZeAwtrdFTB3o6Tq/bhpWcw58nmEP+lyqyHLI9+2Cv/A5yg6tW7DBz0Sa7G5Uzyo6YNcyRyBBBwaeSHmKP9e2ZX7yfaJef9mApwMM2lr/S7Z+M5XSzu3yJ6hK8KSVffUyYX5lmorBtAddB2OVnhf2RVOw14c/PBDPXU4pZ85kEwGRoGMT9x5MYkuqZL1GPXCrG4UACmF+Wtbs4xoPyQmSZ2XUL8WTvFqDWbvUnKlJ051hLgqCXP/duuH6LfjiQmCAmPx+NDVPJmjiUNAk7tnRardY5Oi56FBdj/oX8O+4kitsE/M6PgQe0bBfBf94Z/49/Y50vjdC2RLYC+iets+xO4RdSoq1S3vrUa37XjZWpq+u1Jc2JJxG2XUgd9MYJahXZzph/3wKMw6Bkk1wb5rVWrwF7CzBC/nWa4b6AoqlpXAWqrUDGu 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 12.08.24 12:24, Barry Song wrote: > From: Ryan Roberts > > Add thp_anon= cmdline parameter to allow specifying the default > enablement of each supported anon THP size. The parameter accepts the > following format and can be provided multiple times to configure each > size: > > thp_anon=,[KMG]:;-[KMG]: > > An example: > > thp_anon=16K-64K:always;128K,512K:inherit;256K:madvise;1M-2M:never > > See Documentation/admin-guide/mm/transhuge.rst for more details. > > Configuring the defaults at boot time is useful to allow early user > space to take advantage of mTHP before its been configured through > sysfs. > > Signed-off-by: Ryan Roberts > Co-developed-by: Barry Song > Signed-off-by: Barry Song > --- > -v3: > * support formats as below, Per David's suggestion > thp_anon=16K-64K:always;128K,512K:inherit;256K:madvise;1M-2M:never > * document the relationship between transparent_hugepage > and thp_anon better, Per David; > * > Hi Baolin, > I am taking your Reviewed-by because the code has > changed quite a lot. > > .../admin-guide/kernel-parameters.txt | 9 ++ > Documentation/admin-guide/mm/transhuge.rst | 37 ++++-- > mm/huge_memory.c | 112 +++++++++++++++++- > 3 files changed, 150 insertions(+), 8 deletions(-) > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index f0057bac20fb..d0d141d50638 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -6629,6 +6629,15 @@ > : poll all this frequency > 0: no polling (default) > > + thp_anon= [KNL] > + Format: ,[KMG]:;-[KMG]: > + state is one of "always", "madvise", "never" or "inherit". > + Can be used to control the default behavior of the > + system with respect to anonymous transparent hugepages. > + Can be used multiple times for multiple anon THP sizes. > + See Documentation/admin-guide/mm/transhuge.rst for more > + details. > + > threadirqs [KNL,EARLY] > Force threading of all interrupt handlers except those > marked explicitly IRQF_NO_THREAD. > diff --git a/Documentation/admin-guide/mm/transhuge.rst b/Documentation/admin-guide/mm/transhuge.rst > index 7072469de8a8..528e1a19d63f 100644 > --- a/Documentation/admin-guide/mm/transhuge.rst > +++ b/Documentation/admin-guide/mm/transhuge.rst > @@ -284,13 +284,36 @@ that THP is shared. Exceeding the number would block the collapse:: > > A higher value may increase memory footprint for some workloads. > > -Boot parameter > -============== > - > -You can change the sysfs boot time defaults of Transparent Hugepage > -Support by passing the parameter ``transparent_hugepage=always`` or > -``transparent_hugepage=madvise`` or ``transparent_hugepage=never`` > -to the kernel command line. > +Boot parameters > +=============== > + > +You can change the sysfs boot time default for the top-level "enabled" > +control by passing the parameter ``transparent_hugepage=always`` or > +``transparent_hugepage=madvise`` or ``transparent_hugepage=never`` to the > +kernel command line. > + > +Alternatively, each supported anonymous THP size can be controlled by > +passing ``thp_anon=,[KMG]:;-[KMG]:``, > +where ```` is the THP size and ```` is one of ``always``, > +``madvise``, ``never`` or ``inherit``. > + > +For example, the following will set 16K, 32K, 64K THP to ``always``, > +set 128K, 512K to ``inherit``, set 256K to ``madvise`` and 1M, 2M > +to ``never``:: > + > + thp_anon=16K-64K:always;128K,512K:inherit;256K:madvise;1M-2M:never > + > +``thp_anon=`` may be specified multiple times to configure all THP sizes as > +required. If ``thp_anon=`` is specified at least once, any anon THP sizes > +not explicitly configured on the command line are implicitly set to > +``never``. > + > +``transparent_hugepage`` setting only affects the global toggle. If > +``thp_anon`` is not specified, PMD_ORDER THP will default to ``inherit``. > +However, if a valid ``thp_anon`` setting is provided by the user, the > +PMD_ORDER THP policy will be overridden. If the policy for PMD_ORDER > +is not defined within a valid ``thp_anon``, its policy will default to > +``never``. > > Hugepages in tmpfs/shmem > ======================== > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index 1a12c011e2df..e8eeb8111f6e 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -81,6 +81,7 @@ unsigned long huge_zero_pfn __read_mostly = ~0UL; > unsigned long huge_anon_orders_always __read_mostly; > unsigned long huge_anon_orders_madvise __read_mostly; > unsigned long huge_anon_orders_inherit __read_mostly; > +static bool anon_orders_configured; > > unsigned long __thp_vma_allowable_orders(struct vm_area_struct *vma, > unsigned long vm_flags, > @@ -737,7 +738,10 @@ static int __init hugepage_init_sysfs(struct kobject **hugepage_kobj) > * disable all other sizes. powerpc's PMD_ORDER isn't a compile-time > * constant so we have to do this here. > */ > - huge_anon_orders_inherit = BIT(PMD_ORDER); > + if (!anon_orders_configured) { > + huge_anon_orders_inherit = BIT(PMD_ORDER); > + anon_orders_configured = true; > + } > > *hugepage_kobj = kobject_create_and_add("transparent_hugepage", mm_kobj); > if (unlikely(!*hugepage_kobj)) { > @@ -922,6 +926,112 @@ static int __init setup_transparent_hugepage(char *str) > } > __setup("transparent_hugepage=", setup_transparent_hugepage); > > +static inline int get_order_from_str(const char *size_str) > +{ > + unsigned long size; > + char *endptr; > + int order; > + > + size = memparse(size_str, &endptr); > + order = fls(size >> PAGE_SHIFT) - 1; > + if ((1 << order) & ~THP_ORDERS_ALL_ANON) { > + pr_err("invalid size %s order %d in thp_anon boot parameter\n", > + size_str, order); > + return -EINVAL; > + } > + > + return order; > +} > + > +static inline void set_bits(unsigned long *var, int start, int end) > +{ > + int i; > + > + for (i = start; i <= end; i++) > + set_bit(i, var); > +} > + > +static inline void clear_bits(unsigned long *var, int start, int end) > +{ > + int i; > + > + for (i = start; i <= end; i++) > + clear_bit(i, var); > +} > Do we really need atomic set_bit/clear_bit here or would __set_bit/__clear_bit be sufficient? Also, could we use bitmap_set/bitmap_clear here? -- Cheers, David / dhildenb