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=-8.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_NEOMUTT autolearn=ham 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 B39AFC07542 for ; Mon, 27 May 2019 09:37:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8BEB121721 for ; Mon, 27 May 2019 09:37:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="W/ydN1Qy" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726702AbfE0Jhg (ORCPT ); Mon, 27 May 2019 05:37:36 -0400 Received: from mail-lj1-f196.google.com ([209.85.208.196]:45572 "EHLO mail-lj1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725973AbfE0Jhg (ORCPT ); Mon, 27 May 2019 05:37:36 -0400 Received: by mail-lj1-f196.google.com with SMTP id r76so3319494lja.12 for ; Mon, 27 May 2019 02:37:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=kctcpWSb6oxF6cOmVvTIWupimplFMZMcqonrB1e6g1Y=; b=W/ydN1Qyl8v5mSPMC+AZod6ZCCjUVZFtwLA66FeIV2evNnAKXqdQ36FAjN7b+FpvMm xwnA7XEwzmkfXTPqL2YMTvqqOnsVMUkBPJl+LFZB6K6ytAyPBgTpOkbQelKbD95IYxzN SlnT3a8EsOlYJd3I/5XwbPr+6DRpTKyK3pGlaqb04VUvn10cYC0fe6o+NlRcwkHuCHLj 8PUtSXw/mPLYr+++6p8kGdqhnhdji+IV8SqB3QQxAP/MQGE5k2WqHDXApzTSKRg9QXar 7wvda5YYkNl46ZJ70QVbgTysmgQ+ziuCRz8OeItS9/kGMC4YuBpzYNFZdfEOrfjSCNn2 nG0Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=kctcpWSb6oxF6cOmVvTIWupimplFMZMcqonrB1e6g1Y=; b=aFeivQBy1L9c/QJmGC0s9WR9pAtHFfOsclxiuJzgKZI3oxr2Ngt+j4RY1RfSbo5JLu m3W37hlY58UuWbyKTMdKtum2+JD7M5/ckVv2lD1dECnErRhxX+qVFFSvI1VjiPJ4YPQO Oz3SWkFxShuo8oNeRH1yZVmo5rC11mACA0lAmw71rXiJpjf6c0GtRt4r/9QGTTedxNGM dRSoJkKKbdlNw6wdscKj5wtXcf6EaFUh1/3n3W59Sqat4j4hlYIkO3Qk34oT+pw2TdiD Sge155nXWKg6BipY0KyfQfEnjV9oaRN6c6XzZryCMAAXQC8alHTzg5x1ETlpP1z207oS kUgA== X-Gm-Message-State: APjAAAUPu92WBHObAVh0EkQ8u4c2wDoxZhURDxcVrsR2KuBAQKPYHNGJ 5G6CObVGfvsIXA9lAkMzAdc= X-Google-Smtp-Source: APXvYqy6Wo+D10qjtgxCpBFfuPhQESOXYViGWczEP50sAynUvr8AHNbiFilHgTBskTScDN8+ZfCIrw== X-Received: by 2002:a2e:6545:: with SMTP id z66mr37392510ljb.146.1558949854180; Mon, 27 May 2019 02:37:34 -0700 (PDT) Received: from pc636 ([37.139.158.167]) by smtp.gmail.com with ESMTPSA id t22sm2180872lje.58.2019.05.27.02.37.32 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 27 May 2019 02:37:33 -0700 (PDT) From: Uladzislau Rezki X-Google-Original-From: Uladzislau Rezki Date: Mon, 27 May 2019 11:37:26 +0200 To: Hillf Danton Cc: "Uladzislau Rezki (Sony)" , Andrew Morton , "linux-mm@kvack.org" , Roman Gushchin , Michal Hocko , Matthew Wilcox , LKML , Thomas Garnier , Oleksiy Avramchenko , Steven Rostedt , Joel Fernandes , Thomas Gleixner , Ingo Molnar , Tejun Heo Subject: Re: [PATCH v2 3/4] mm/vmap: get rid of one single unlink_va() when merge Message-ID: <20190527093726.fmbsgyek6ofrniup@pc636> References: <20190527030712.15472-1-hdanton@sina.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190527030712.15472-1-hdanton@sina.com> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 27, 2019 at 11:07:12AM +0800, Hillf Danton wrote: > > On Mon, 27 May 2019 05:22:28 +0800 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. > > > > Signed-off-by: Uladzislau Rezki (Sony) > > --- > > Acked-by: Hillf Danton > Thanks! > > mm/vmalloc.c | 9 +++------ > > 1 file changed, 3 insertions(+), 6 deletions(-) > > > > diff --git a/mm/vmalloc.c b/mm/vmalloc.c > > index b553047aa05b..6f91136f2cc8 100644 > > --- a/mm/vmalloc.c > > +++ b/mm/vmalloc.c > > @@ -718,9 +718,6 @@ merge_or_add_vmap_area(struct vmap_area *va, > > /* Check and update the tree if needed. */ > > augment_tree_propagate_from(sibling); > > > > - /* Remove this VA, it has been merged. */ > > - unlink_va(va, root); > > - > > /* Free vmap_area object. */ > > kmem_cache_free(vmap_area_cachep, va); > > > > @@ -745,12 +742,12 @@ merge_or_add_vmap_area(struct vmap_area *va, > > /* Check and update the tree if needed. */ > > augment_tree_propagate_from(sibling); > > > > - /* Remove this VA, it has been merged. */ > > - unlink_va(va, root); > > + /* Remove this VA, if it has been merged. */ > > + if (merged) > > + unlink_va(va, root); > > > The change makes the code much easier to read, thanks. > What is more, checking merged makes the polished comment unnecessary, imo. > And it can be applied, I think, to the above hunk. > That is odd. Will remove it. -- Vlad Rezki