From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 74EADC48BF6 for ; Mon, 4 Mar 2024 17:37:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=cZk+xUeWNDRcc2N58GvMoZ9na+xLoooUUWC4Ebv1YPk=; b=HMkb2hXYUN/II0 +/HnGF1ihG1ThPPlHwSBvgBt/vA+wn2DobXXLjFB/mAPZFkF2Z70RNy/Ci7H3cCvjHpU4t49s2bh1 UmPwyxs+MMDiUzt7VgRIkrY5UsY0aVRFPbsLB8OyCo3jRrmnW9GWR0TuvxMqD8PMx9dHpgd/PUPn9 RxyKr8Vnb2d/2OtKMjdGgyFa5/L2fWp3q2CUYmNmkcNgYcN3/E32hTzMrfldGIRkvSUjYt74saCgj uUMJfj2uslIiLkxd6RtYNJ5UrBaNmspjKh/PLMQPJ752QOBcYrikX5ntWQkxSMyHIQM4Y6emzVHKD kloCHMCmD0gD25gheVvQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rhCG4-0000000A1lx-41lG; Mon, 04 Mar 2024 17:37:48 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rhCG2-0000000A1lS-0HgV for linux-arm-kernel@lists.infradead.org; Mon, 04 Mar 2024 17:37:47 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id B8AAF61132; Mon, 4 Mar 2024 17:37:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1A42AC433C7; Mon, 4 Mar 2024 17:37:42 +0000 (UTC) Date: Mon, 4 Mar 2024 17:37:40 +0000 From: Catalin Marinas To: Ryan Roberts Cc: Andrew Morton , Mark Rutland , John Hubbard , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org Subject: Re: [PATCH 2/2] arm64/mm: Improve comment in contpte_ptep_get_lockless() Message-ID: References: <20240226120321.1055731-1-ryan.roberts@arm.com> <20240226120321.1055731-3-ryan.roberts@arm.com> <089f689d-f8dd-48ba-b6b0-6f91aa3b86f1@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <089f689d-f8dd-48ba-b6b0-6f91aa3b86f1@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240304_093746_198975_467C8902 X-CRM114-Status: GOOD ( 22.66 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Mar 04, 2024 at 12:54:23PM +0000, Ryan Roberts wrote: > On 01/03/2024 18:47, Catalin Marinas wrote: > > On Mon, Feb 26, 2024 at 12:03:21PM +0000, Ryan Roberts wrote: > >> Make clear the atmicity/consistency requirements of the API and how we > >> achieve them. > >> > >> Link: https://lore.kernel.org/linux-mm/Zc-Tqqfksho3BHmU@arm.com/ > >> Signed-off-by: Ryan Roberts > >> --- > >> arch/arm64/mm/contpte.c | 24 ++++++++++++++---------- > >> 1 file changed, 14 insertions(+), 10 deletions(-) [...] > > Throughout the callers of this function, I couldn't find one where it > > matters. So I concluded that they don't need the dirty state. Normally > > the dirty state is passed to the page flags, so not lost after the pte > > has been cleaned. > > I agree we can simplify the semantics. But I think its better done in a separate > series (which I previously linked). > > What's the bottom line here? Are you ok with this comment as a short term > solution for now, or do you want something more radical (i.e. push to get the > series that does these simplifications reviewed and in time for v6.9). > > I still believe the current ptep_get_lockless() implementation is correct. So > given I have a plan to simplify in the long run, I hope we can still get this > series into v6.9 as planned. Yes, I'm fine with this patch. Assuming Andrew picked them up: Reviewed-by: Catalin Marinas I'd like to get the simplification in as well at some point as I think our ptep_get_lockless() is unnecessarily complex for most use-cases. -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel