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 X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3AF44C282CE for ; Wed, 22 May 2019 18:19:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 174E9216F4 for ; Wed, 22 May 2019 18:19:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558549156; bh=Lj+UQSKOBWjtRSU8mmwyChOpiwRlOQuuXNdlNMg9qOk=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=SpzK03T9sSG6UDXK/PV02R8UUiPImzPkaT/RqNkidbFKxQdKjCYdT3GcZDgkgnh4Q q5Yz6iNMxuru8k1jKHN9H6XghN8+JJPJ6+E71lo0/4FzC+r9IT0Pl3oR4sGFjiWMjU 4gZ9a8u75qxne76CVxUB2Nzkh/hOIgFgNNCvLPdk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729615AbfEVSTP (ORCPT ); Wed, 22 May 2019 14:19:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:48284 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729517AbfEVSTM (ORCPT ); Wed, 22 May 2019 14:19:12 -0400 Received: from localhost.localdomain (c-73-223-200-170.hsd1.ca.comcast.net [73.223.200.170]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id EC36121473; Wed, 22 May 2019 18:19:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558549152; bh=Lj+UQSKOBWjtRSU8mmwyChOpiwRlOQuuXNdlNMg9qOk=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=Kxch2P6yoqn2ghOf6Zu5Akc+n+E7NcUW2VuwDGYxynrln25xvzIwwgleLCMAr+Cjd dOpYDPHt3h+O0vEg9NqJj5RIaRl7eyVLSzCnpO2BOAZoeObsWf7Di/S85ZqKLTBoEt zb5wpD9kIFFS/2atJeKvU6VaVWp18Dac0S4xG92k= Date: Wed, 22 May 2019 11:19:11 -0700 From: Andrew Morton To: "Uladzislau Rezki (Sony)" Cc: Roman Gushchin , Michal Hocko , Matthew Wilcox , linux-mm@kvack.org, LKML , Thomas Garnier , Oleksiy Avramchenko , Steven Rostedt , Joel Fernandes , Thomas Gleixner , Ingo Molnar , Tejun Heo Subject: Re: [PATCH 3/4] mm/vmap: get rid of one single unlink_va() when merge Message-Id: <20190522111911.963fbb4950e051a35e92887c@linux-foundation.org> In-Reply-To: <20190522150939.24605-3-urezki@gmail.com> References: <20190522150939.24605-1-urezki@gmail.com> <20190522150939.24605-3-urezki@gmail.com> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 22 May 2019 17:09:38 +0200 "Uladzislau Rezki (Sony)" wrote: > It does not make sense to try to "unlink" the node that is > definitely not linked with a list nor tree. On the first > merge step VA just points to the previously disconnected > busy area. > > On the second step, check if the node has been merged and do > "unlink" if so, because now it points to an object that must > be linked. Again, what is the motivation for this change? Seems to be a bit of a code/logic cleanup, no significant runtime effect?