From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4670137BE9E for ; Tue, 3 Mar 2026 08:57:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772528252; cv=none; b=hchJ/i+bMw+YW4IoF3AyzsT7jk72xYYeXISNJGgu7iSmoqyBK0iukJs8h88fxacy7L4F3iAsKdTf6yklMPg/nLysDB7m0Em+hr2i+ecVa3EbwdNSA+FhK8WBInDb8ih8gBH2ceL2aM8g19Wtat9HdCfhuyKWcM2ykgcox/BCN6Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772528252; c=relaxed/simple; bh=9iVkSiANjtujwUTPjMcA7Zj0OXuBBdA6W+TyRsKkQnY=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=i0NZdv5s9w0I90D5qT/NllU+NJm3J+bnCoI3dbOlGbVtkqFhkpqlBj+CV6ZlkLyw20z79WbbnDB/MhueTXdDeKm1IL/rWd4eO2QY73PqxccTWjO0iEz/mNF1TDULRIGuFjGScJw4gQvQXUayf7Kd0TDo61KcFYPMJyDSOEYjZhg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=O5hEK57E; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="O5hEK57E" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D8EC8C116C6; Tue, 3 Mar 2026 08:57:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772528251; bh=9iVkSiANjtujwUTPjMcA7Zj0OXuBBdA6W+TyRsKkQnY=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=O5hEK57Ei8XjMvC7hpqZ/a01ted5za1wlZJWLHFpSnEkGrdR8c7fp5LPt7AlzdGmB o7yVyqgFloJBFvX+xCgz8g/RR59cHBa4bwr+RT2DtN5nSgqQCiCKWwngsrB018JcFZ i6VS12Vyx1rS8VbQajaLcmD+cKS2QiKEjFf/n366wr4Rh5HWgNmpLT68fbQ4dbF/yW CPRh48YwWwx7IxSybdWZSYnvvIf6xcXbKrab5qJk57ofvT8cqm7ot4HtZI53Vrufe2 wm3Vhlnl3P0ZHwIiJGi4LRdtKmMPAYFaD2BCxl5xlejc2RaDfQGDFIEZFFnydTzVAP a5e0zcLHMVIrg== Message-ID: Date: Tue, 3 Mar 2026 09:57:23 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 5/6] mm: support batched checking of the young flag for MGLRU To: Baolin Wang , akpm@linux-foundation.org Cc: catalin.marinas@arm.com, will@kernel.org, lorenzo.stoakes@oracle.com, ryan.roberts@arm.com, Liam.Howlett@oracle.com, vbabka@suse.cz, rppt@kernel.org, surenb@google.com, mhocko@suse.com, riel@surriel.com, harry.yoo@oracle.com, jannh@google.com, willy@infradead.org, baohua@kernel.org, dev.jain@arm.com, axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com, hannes@cmpxchg.org, zhengqi.arch@bytedance.com, shakeel.butt@linux.dev, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <7f2973f0-0a34-4e4f-8ed6-13c531f77453@kernel.org> <3701c315-b19c-4c87-aff3-cc76e1009a43@linux.alibaba.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 8bit >>                  unsigned long pfn; >>                  struct folio *folio; >> -               pte_t ptent = ptep_get(pte + i); >> +               pte_t ptent = ptep_get(pte); >>   +               nr = 1; >>                  total++; >>                  walk->mm_stats[MM_LEAF_TOTAL]++; >>   @@ -3533,7 +3534,16 @@ static bool walk_pte_range(pmd_t *pmd, >> unsigned long start, unsigned long end, >>                  if (!folio) >>                          continue; > > Thanks for the code. I considered simplifying the logic this way, but > this logic would be incorrect. Because the 'start' can be updated by the > get_next_vma() below, when we goto restart, we will get a new 'i' value > by 'pte_index(start)', so I kept the 'i' variable. You're right, that's some horrible, horrible code. -- Cheers, David