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 06D57156230 for ; Tue, 17 Dec 2024 06:43:41 +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=1734417823; cv=none; b=imtPXXyYI3SGfC3wHweN916NqinvTziPR3ijECl2p3qSvbVkQ+HFnPAsOvRp0j/MFAfhpQy5cKMnncsfy812n7X9F8sbvX0US0Ho//eaStPfl/5SAJesdSHuAo0sws5toXs2EIe0tLaKltkUkHSSh7WgpjIXU/W7YwwfV4XA4oo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734417823; c=relaxed/simple; bh=jveWgxfLXLRGkrv5az/fOu+EI6bEi3NCZ0MMgDBzS9U=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=lp4nCwd0Fd/M8xm9BUmjMqnQvMFrbvX+EYeeKeSQ4csR03R3HBnHIyBGmkZHwqRoFOdYASPEHce3xh9HyDYD/S8FFiqh6XtMUKcjOa7Xp3K59K37xB18j/iFP/9ZS7tR1S1Jlo0aFSAs50y17urQMv5GmEtAe4X68pgYzIIfczk= 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 66C7A1007; Mon, 16 Dec 2024 22:44:09 -0800 (PST) Received: from [10.57.91.184] (unknown [10.57.91.184]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id BC3F43F528; Mon, 16 Dec 2024 22:43:35 -0800 (PST) Message-ID: <0a33f5c1-c974-4d4a-94dd-6741399e186e@arm.com> Date: Tue, 17 Dec 2024 06:43:34 +0000 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: [RFC PATCH 01/12] khugepaged: Rename hpage_collapse_scan_pmd() -> ptes() Content-Language: en-GB To: Matthew Wilcox , Dev Jain Cc: akpm@linux-foundation.org, david@redhat.com, kirill.shutemov@linux.intel.com, anshuman.khandual@arm.com, catalin.marinas@arm.com, cl@gentwo.org, vbabka@suse.cz, mhocko@suse.com, apopple@nvidia.com, dave.hansen@linux.intel.com, will@kernel.org, baohua@kernel.org, jack@suse.cz, srivatsa@csail.mit.edu, haowenchao22@gmail.com, hughd@google.com, aneesh.kumar@kernel.org, yang@os.amperecomputing.com, peterx@redhat.com, ioworker0@gmail.com, wangkefeng.wang@huawei.com, ziy@nvidia.com, jglisse@google.com, surenb@google.com, vishal.moola@gmail.com, zokeefe@google.com, zhengqi.arch@bytedance.com, jhubbard@nvidia.com, 21cnbao@gmail.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20241216165105.56185-1-dev.jain@arm.com> <20241216165105.56185-2-dev.jain@arm.com> From: Ryan Roberts In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 17/12/2024 04:18, Matthew Wilcox wrote: > On Mon, Dec 16, 2024 at 10:20:54PM +0530, Dev Jain wrote: >> -static int hpage_collapse_scan_pmd(struct mm_struct *mm, >> +static int hpage_collapse_scan_ptes(struct mm_struct *mm, > > i don't think this is necessary at all. you're scanning a pmd. > you might not be scanning in order to collapse to a pmd, but pmd > is the level you're scanning at. > Sorry Matthew, I don't really understand this statement. Prior to the change we were scanning all PTE entries in a PTE table with the aim of collapsing to a PMD entry. After the change we are scanning some PTE entries in a PTE table with the aim of collapsing to either to a multi-PTE-mapped folio or a single-PMD-mapped folio. So personally I think "scan_pmd" was a misnomer even before the change - we are scanning the ptes.