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charset=us-ascii Content-Disposition: inline In-Reply-To: <54774e70-1e94-44f5-b318-fdfd5115041d@p183> X-Rspamd-Queue-Id: 04EA74000E X-Rspam-User: X-Stat-Signature: aexrskb9hman8f3icas3six67eesteqm X-Rspamd-Server: rspam03 X-HE-Tag: 1707853172-470030 X-HE-Meta: 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 2T2gkZWm +kAsEni+xVPNaDw8/gusdzyAvYzEuy25TtfrB6b+5fjaNJCbjC00KcnGBrDXze1wbQ5k+bn0wnhymFI+S1GnqH17fiL8w228otn7+cb66SY2tSnM8HQyjleXm8twbNla4RlsqJBSARxyclrRRqqrUDr44MhfUbgYyJwlXU6Sn+1kG5kPn21ZVeUMpKVhM4Nc+NHZo85yrTKjWpQ5IVypD7Xw+kOA9igKI5c1mYJ3ChVtwO4UW2lOustpOJIXkJupmmWw/2Ai1XzcBmI6BeItQm5+ZGq2w35DuvS0efSkVB1XUFNtlf5wX5kOyIKS3/d2hw0m0zBy6Xa73lNwYDu/12h05Jmpm9zTYwnYrg78RqEqSl29OqQTXiC4HTX1zk+WSi/UFvqiuGfz8dCCpbLNG4aTGfw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000012, 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 Tue, Feb 13, 2024 at 09:51:01PM +0300, Alexey Dobriyan wrote: > On Fri, Feb 09, 2024 at 04:41:36PM -0800, Kees Cook wrote: > > On Fri, Feb 09, 2024 at 03:30:37PM +0300, Alexey Dobriyan wrote: > > > On Mon, Feb 05, 2024 at 04:48:08AM -0800, Kees Cook wrote: > > > > On Mon, Feb 05, 2024 at 12:51:43PM +0300, Alexey Dobriyan wrote: > > > > > +#define ARCH_AT_PAGE_SHIFT_MASK \ > > > > > + do { \ > > > > > + u32 val = 1 << 12; \ > > > > > + if (boot_cpu_has(X86_FEATURE_PSE)) { \ > > > > > + val |= 1 << 21; \ > > > > > + } \ > > > > > + if (boot_cpu_has(X86_FEATURE_GBPAGES)) { \ > > > > > + val |= 1 << 30; \ > > > > > + } \ > > > > > > > > Can we use something besides literal "12", "21", and "30" values here? > > > > > > Ehh, no, why? Inside x86_64 the page shifts are very specific numbers, > > > they won't change. > > > > Well, it's nicer to have meaningful words to describe these things. > > Not really. Inside specific arch page shifts are fixed, so using names > is just more macros one need to remember. > > If I were to invent names (which I wouldn't), the best names are > > PAGE_SHIFT > PAGE_SHIFT2 > PAGE_SHIFT3 > ... > > with PAGE_SHIFT2, PAGE_SHIFT3 being optional macros if arch doesn't support > multiple page sizes. > > > In fact, PAGE_SHIFT already exists for 12, and HPAGE_SHIFT already exists > > for 21. Please use those, and add another, perhaps GBPAGE_SHIFT, for 30. > > HPAGE_SHIFT is bad name, H doesn't describe anything unless arch is > known. Hugepages is marketing name. If GBPAGE_SHIFT is good name, > then HPAGE_SHIFT is bad name, it should've been MBPAGE_SHIFT, which > wrong because it is 2 MiB not 1 MiB. > > BTW parisc has REAL_HPAGE_SHIFT ! Sure, I mean, we've got an x86-specific function here, so let's use the x86-specific macros we already have for 12 and 21, and then add the missing one for 30. -- Kees Cook