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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 96473C433E0 for ; Thu, 4 Feb 2021 14:53:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 646D864DBA for ; Thu, 4 Feb 2021 14:53:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236930AbhBDOxd (ORCPT ); Thu, 4 Feb 2021 09:53:33 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:32985 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236886AbhBDOwK (ORCPT ); Thu, 4 Feb 2021 09:52:10 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612450243; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=BFhiSabHbTK6awvWbCXdRee7Kg5oltAX0WknJbnHBPY=; b=Qc/n4OxYVnj0HpHUkAGyh23if2dWgUigEK2c52lUP/80AaxtwLIfi748jjA8cNT3EXH/Ya WVoIGm6sWFw3KV6+v1jACpEDrM8IvtkcIj6hlEuZux5IiYVqO+eryCNyYz5if6wSMmwSpT H4U3hLg+Oa1rce7YHBzFGsk1p+8TZzo= Received: from mail-qt1-f197.google.com (mail-qt1-f197.google.com [209.85.160.197]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-170-8gQO7cEYOPefJxKAyFDEyw-1; Thu, 04 Feb 2021 09:50:39 -0500 X-MC-Unique: 8gQO7cEYOPefJxKAyFDEyw-1 Received: by mail-qt1-f197.google.com with SMTP id m21so2731766qtp.6 for ; Thu, 04 Feb 2021 06:50:39 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=BFhiSabHbTK6awvWbCXdRee7Kg5oltAX0WknJbnHBPY=; b=MYku1y5iQZkC3x2Tc0ZuFqMjgDgcX2byc6TiJP7xrmywrfjBUNFSTB8PeQDU/QiqYE atMJYymlf81N7HU2OMCGATk/Ob2MOlaXViJzLSO93hC2jMXS5D07H8h0ORchQEkOF5Od 1NNkD8g8nLqLMCLlOvkzxyvOgiNcrRdngCqiKDQUPf60yAxNC+rARSiNcB9n3yXahYO4 mUUPp6mNoTFfAYqYbfV+RCtaEZE028oLDuJn+2bArQyE+GcTBaeUnokx3WuCYE7VN+aD wb2NtXVc250/pntOanH3Ixbo6ruN77h/9HuyJ39YlXjR2D7Pc/5LV03ijAXIdQQZAFcD EOfQ== X-Gm-Message-State: AOAM533irv+vCvg0C0z+hyFZdRYKKQYGq10xcJrCE9JP9WL7I6LWcpKl x5YvuxyAmfOLZJR7z036M/sPdaGHdsOVsZEPCwoWDMTSm3Clc62NifHQ3i0KOLf2g8BavxAnArM T6KBcPb9mK9yZXQLwwWNw0+Qp X-Received: by 2002:a0c:ea22:: with SMTP id t2mr7988231qvp.49.1612450239370; Thu, 04 Feb 2021 06:50:39 -0800 (PST) X-Google-Smtp-Source: ABdhPJyPUkNyHWb+UWJMNEc3cGhB+rAC8gjZRsIwVoa3hAW/lFIuyqXBQa1vuvjUS9s3w6r1pDZpIg== X-Received: by 2002:a0c:ea22:: with SMTP id t2mr7988208qvp.49.1612450239176; Thu, 04 Feb 2021 06:50:39 -0800 (PST) Received: from xz-x1.redhat.com (bras-vprn-toroon474qw-lp130-20-174-93-89-182.dsl.bell.ca. [174.93.89.182]) by smtp.gmail.com with ESMTPSA id e14sm4697589qte.18.2021.02.04.06.50.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 04 Feb 2021 06:50:38 -0800 (PST) From: Peter Xu To: linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: Kirill Shutemov , Wei Zhang , Mike Rapoport , Matthew Wilcox , Miaohe Lin , Andrea Arcangeli , peterx@redhat.com, Gal Pressman , Jan Kara , Jann Horn , Andrew Morton , Kirill Tkhai , Linus Torvalds , Mike Kravetz , Jason Gunthorpe , David Gibson , Christoph Hellwig Subject: [PATCH v2 2/4] hugetlg: Break earlier in add_reservation_in_range() when we can Date: Thu, 4 Feb 2021 09:50:31 -0500 Message-Id: <20210204145033.136755-3-peterx@redhat.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20210204145033.136755-1-peterx@redhat.com> References: <20210204145033.136755-1-peterx@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org All the regions maintained in hugetlb reserved map is inclusive on "from" but exclusive on "to". We can break earlier even if rg->from==t because it already means no possible intersection. This does not need a Fixes in all cases because when it happens (rg->from==t) we'll not break out of the loop while we should, however the next thing we'd do is still add the last file_region we'd need and quit the loop in the next round. So this change is not a bugfix (since the old code should still run okay iiuc), but we'd better still touch it up to make it logically sane. Reviewed-by: Mike Kravetz Reviewed-by: Miaohe Lin Signed-off-by: Peter Xu --- mm/hugetlb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index d2859c2aecc9..9e6ea96bf33b 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -377,7 +377,7 @@ static long add_reservation_in_range(struct resv_map *resv, long f, long t, /* When we find a region that starts beyond our range, we've * finished. */ - if (rg->from > t) + if (rg->from >= t) break; /* Add an entry for last_accounted_offset -> rg->from, and -- 2.26.2