From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 3686B647; Tue, 7 Jan 2025 09:24:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736241845; cv=none; b=osVFP5EfYyP0+rVSswKY0QMqUb0QI3DfLwN0UiLpax78QavNv3B3LW7k/NMP9t+1v2xrKkrIN3Rb3zFJPDaicAV/kz1+BmOe5EAhsVoR9AX7eJ2ZkM7sWZzPsOK0qhPOJso7Ks5UgcLI80RhVDm/veDotYDjAg02KpWQb/kOEjI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736241845; c=relaxed/simple; bh=DFJhVvdeLGk2efSvJopONsRNtRHM8RshXpbuce0z+N4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Vai0vnPDd4IvubWRqHzYG4b2XkeHhLFJY8c9RH8/UwxmfHZbrL/ru+P/gE3P1Tqgwnr3ApRRP4Y8Ua/H71AHu5n7EszDh6m77CZwJo6vlJytkJzyFTwiiwIlnjb5jS/qm7EfmO16Sp9Ibtc/5SgbMLDQ7qvsF3ZIDE8xdrck08Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id ADFCE143D; Tue, 7 Jan 2025 01:24:31 -0800 (PST) Received: from [10.57.93.53] (unknown [10.57.93.53]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 96F593F66E; Tue, 7 Jan 2025 01:23:54 -0800 (PST) Message-ID: <83df51a5-5eb9-4470-92a1-e69fd12b98b4@arm.com> Date: Tue, 7 Jan 2025 10:23:52 +0100 Precedence: bulk X-Mailing-List: linux-hexagon@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 07/15] mm: pgtable: introduce pagetable_dtor() To: Qi Zheng , Alexander Gordeev Cc: peterz@infradead.org, palmer@dabbelt.com, tglx@linutronix.de, david@redhat.com, jannh@google.com, hughd@google.com, yuzhao@google.com, willy@infradead.org, muchun.song@linux.dev, vbabka@kernel.org, lorenzo.stoakes@oracle.com, akpm@linux-foundation.org, rientjes@google.com, vishal.moola@gmail.com, arnd@arndb.de, will@kernel.org, aneesh.kumar@kernel.org, npiggin@gmail.com, dave.hansen@linux.intel.com, rppt@kernel.org, ryan.roberts@arm.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-kernel@vger.kernel.org, x86@kernel.org, linux-arch@vger.kernel.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, loongarch@lists.linux.dev, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-openrisc@vger.kernel.org, linux-sh@vger.kernel.org, linux-um@lists.infradead.org References: <8ada95453180c71b7fca92b9a9f11fa0f92d45a6.1735549103.git.zhengqi.arch@bytedance.com> Content-Language: en-GB From: Kevin Brodsky In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On 06/01/2025 14:23, Qi Zheng wrote: > On 2025/1/6 20:36, Alexander Gordeev wrote: >> On Mon, Jan 06, 2025 at 06:55:58PM +0800, Qi Zheng wrote: >>>>> +static inline void pagetable_dtor(struct ptdesc *ptdesc) >>>>> +{ >>>>> +    struct folio *folio = ptdesc_folio(ptdesc); >>>>> + >>>>> +    ptlock_free(ptdesc); >>>>> +    __folio_clear_pgtable(folio); >>>>> +    lruvec_stat_sub_folio(folio, NR_PAGETABLE); >>>>> +} >>>>> + >>>> >>>> If I am not mistaken, it is just pagetable_pte_dtor() rename. >>>> What is the point in moving the code around? >>> >>> No, this is to unify pagetable_p*_dtor() into pagetable_dtor(), so >>> that we can move pagetable_dtor() to __tlb_remove_table(), and then >>> ptlock and PTE page can be freed together through RCU, which is >>> also the main purpose of this patch series. >> >> I am only talking about this patch. pagetable_dtor() code above is >> the same pagetable_pte_dtor() below - it is only the function name >> that changed. So why to move the function body? Anyway, that is > > Ah, I just don't want to put pagetable_dtor() in between > pagetable_pte_ctor() and ___pte_offset_map(), so I moved it above > pagetable_pte_ctor(). No other special reason. 😉 I think inserting pagetable_dtor() there makes sense. I wouldn't say that pagetable_pte_dtor() is being renamed to pagetable_dtor(), because in fact this patch replaces all of pagetable_{pte,pmd,pud}_dtor() with pagetable_dtor(), and it is arguably clearer to insert the latter higher up in mm.h. FWIW my follow-up series introduces a common __pagetable_dtor(), inserted below pagetable_ctor() [1]. - Kevin [1] https://lore.kernel.org/linux-mm/20250103184415.2744423-2-kevin.brodsky@arm.com/