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[195.135.220.15]) by mx.google.com with ESMTPS id c14si27929307ejb.99.2019.08.05.06.28.50 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 05 Aug 2019 06:28:51 -0700 (PDT) Received-SPF: pass (google.com: domain of vbabka@suse.cz designates 195.135.220.15 as permitted sender) client-ip=195.135.220.15; Authentication-Results: mx.google.com; spf=pass (google.com: domain of vbabka@suse.cz designates 195.135.220.15 as permitted sender) smtp.mailfrom=vbabka@suse.cz X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 804CCACB4; Mon, 5 Aug 2019 13:28:50 +0000 (UTC) Subject: Re: [PATCH] fork: Improve error message for corrupted page tables To: "Prakhya, Sai Praneeth" , Andrew Morton Cc: "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "Hansen, Dave" , Ingo Molnar , Peter Zijlstra References: <20190730221820.7738-1-sai.praneeth.prakhya@intel.com> <20190731152753.b17d9c4418f4bf6815a27ad8@linux-foundation.org> <20190731212052.5c262ad084cbd6cf475df005@linux-foundation.org> From: Vlastimil Babka Openpgp: preference=signencrypt Autocrypt: addr=vbabka@suse.cz; 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Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit 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 8/2/19 8:46 AM, Prakhya, Sai Praneeth wrote: >>>>> +static const char * const resident_page_types[NR_MM_COUNTERS] = { >>>>> + "MM_FILEPAGES", >>>>> + "MM_ANONPAGES", >>>>> + "MM_SWAPENTS", >>>>> + "MM_SHMEMPAGES", >>>>> +}; >>>> >>>> But please let's not put this in a header file. We're asking the >>>> compiler to put a copy of all of this into every compilation unit >>>> which includes the header. Presumably the compiler is smart enough >>>> not to do that, but it's not good practice. >>> >>> Thanks for the explanation. Makes sense to me. >>> >>> Just wanted to check before sending V2, Is it OK if I add this to >>> kernel/fork.c? or do you have something else in mind? >> >> I was thinking somewhere like mm/util.c so the array could be used by other >> code. But it seems there is no such code. Perhaps it's best to just leave fork.c as >> it is now. > > Ok, so does that mean have the struct in header file itself? If the struct definition (including the string values) was in mm/util.c, there would have to be a declaration in a header. If it's in fork.c with the only users, there doesn't need to be separate declaration in a header. > Sorry! for too many questions. I wanted to check with you before changing > because it's *the* fork.c file (I presume random changes will not be encouraged here) > > I am not yet clear on what's the right thing to do here :( > So, could you please help me in deciding. fork.c should be fine, IMHO > Regards, > Sai >