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b=bZrL8Cym9mcGQkJcKIk7xOUgiBjZIJX94P+HYk4/+Y98Rcj+dtnsz2aAJKHXYSjcP crRdTnHRa+gDVBDG32Gh8c2MqG8su06iqxXVIfZLr+asmvfVqRc5Rl+QiazfLF3ib7 5mnAvpmPaYX75J1rq0YD+FW3QYIO9xsMzeQq3b/J8u/OZYHujlTzEU0QbtWhIl2nKe MSEgzBWAyJp6Uw3/tBOXmG3KDJwf5OkuOjD040J2mhSCdB9CPGxUbINA5LTqwVkhpq Gaegv6rmFp9/gxAZuGvCw3YBo28aoTkAxX9IQaOZ27ytBKyrVfd+vufJEaGNnUzhXW TIILx9bal2q6A== Date: Wed, 26 Aug 2026 12:04:21 +0100 From: "Lorenzo Stoakes (ARM)" To: Vernon Yang Cc: "David Hildenbrand (Arm)" , akpm@linux-foundation.org, nico.pache@linux.dev, ryan.roberts@arm.com, dev.jain@arm.com, baohua@kernel.org, lance.yang@linux.dev, usama.arif@linux.dev, zokeefe@google.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, stable@vger.kernel.org, Vernon Yang Subject: Re: [PATCH v3 1/3] mm: khugepaged: fix swap entry value to folio_pfn() Message-ID: References: <6a9c2369-5589-4f2a-bcfe-c6e3b46a1ccd@gmail.com> <42695df0-3962-4126-9afb-9a1905d096a0@kernel.org> <49aa013f-f613-42be-bc58-35956ef189de@kernel.org> <330789dd-94e2-4827-abdd-23671263608f@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <330789dd-94e2-4827-abdd-23671263608f@gmail.com> X-Stat-Signature: 9u1ik17u76uxqeztbzx1zgqcwkqkifwh X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 652EF160003 X-Rspam-User: X-HE-Tag: 1787742269-627888 X-HE-Meta: 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 U7yBy604 lANxSln1L7pJ53gUr84t6zHYjppoYIjg1vIJUaZysvv+uz7UJBSIbrAFzfRQ5Y/Rj6ak/M1m+R4E8W7Pb3YFCX2AkBJLeAysCNX6ZZ9x1rSR1+6wCePOiu51CGYdUFW2gtvCnxx31/7+CgsYzfXhj8h+X6JPADlqrNTQRBCux3qhKS7XN0PmtHCD2EpDWWY0wq3oCWhzQ3adpYfxozTx+ewGONJE2VP/Tz0dAzUOpwzNJF1aAShkn06Dwx/RKcUUdWcMd2iqn1Eg5WcfPfdCSgxABZVbfEVZ8okbwAevIvlBESMM= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Aug 26, 2026 at 05:21:51PM +0800, Vernon Yang wrote: > On Wed, Aug 26, 2026 at 09:35:38AM +0100, Lorenzo Stoakes (ARM) wrote: > > On Wed, Aug 26, 2026 at 10:24:56AM +0200, David Hildenbrand (Arm) wrote: > > > On 8/26/26 10:16, David Hildenbrand (Arm) wrote: > > > > On 8/26/26 10:11, Lorenzo Stoakes (ARM) wrote: > > > >> On Wed, Aug 26, 2026 at 10:08:58AM +0200, David Hildenbrand (Arm) wrote: > > > >>> > > > >>> Elaborate. > > > >> > > > >> It's overly long, I read it and am confused as to what is 'problematic' or not, > > > >> it reads weirdly in English and pfn_xxx is the usual convention for naming of > > > >> pfn's anyway. > > > > > > > > Excuse me, what? Are you now just making up arguments? > > > To clarify, we have various users of "xxx_pfn" in the tree and I fail to see how > > > "this is a problematic pfn" -> "problematic_pfn" is odd and why > > > "pfn_problematic" would be any clearer. > > > > > > I do agree with the "problematic" aspect. "failed" might indeed be nicer. > > > > Right yeah. Mostly the push back is on the word being a bit confusing. Fair > > enough on the pfn thing, failed_pfn is actually the nicest name suggested so far > > :) > > failed_pfn is good to me. Thanks. > > > I still think: > > > > if (result == SCAN_SUCCEED) { > > ... > > trace_mm_khugepaged_scan_file(mm, -1, file, present, swap, result); > > } else { > > trace_mm_khugepaged_scan_file(mm, failed_pfn, file, present, > > swap, result); > > } > > > > Is a little neater as then it's only on the failure path that we trace the > > failed pfn, and otherwise we explicitly -1. > > I understand what you're trying to say, but personally it isn't necessary, > because failed_pfn defaults to -1, and one > trace_mm_khugepaged_scan_file() already covers it. > > If everyone clearly expresses that they want two > trace_mm_khugepaged_scan_file(), please let me know explicitly. Thanks! See David's reply, we'd like to go with this thanks. -- Cheers, Lorenzo