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=-15.8 required=3.0 tests=BAYES_00,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_RED 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 8209DC4332D for ; Sat, 13 Mar 2021 05:08:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 66C4864FD9 for ; Sat, 13 Mar 2021 05:08:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230349AbhCMFHk (ORCPT ); Sat, 13 Mar 2021 00:07:40 -0500 Received: from mail.kernel.org ([198.145.29.99]:41590 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230441AbhCMFHX (ORCPT ); Sat, 13 Mar 2021 00:07:23 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id C71E564F87; Sat, 13 Mar 2021 05:07:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1615612043; bh=DAdzuv+DDliyMTDupt43ZegZpf6p0LEoTKsrBSuuGy4=; h=Date:From:To:Subject:In-Reply-To:From; b=Mnt+kMXnA/BdAJqZQgFYbjZR4jjynqn8OyeYv173XnTzSbunzCX8f76zxr/lBDV1g 6DU6qgUd2dYSwoKXEs1oBYOGSnoBdiFuReV/oK/r457vDpvum0QSG9qXATu1ajGbTs /K0z2l2r7UI9KO7DhW7X6VA7Bg06QyV2s6XQIf7I= Date: Fri, 12 Mar 2021 21:07:22 -0800 From: Andrew Morton To: aarcange@redhat.com, adobriyan@gmail.com, airlied@linux.ie, akpm@linux-foundation.org, daniel@ffwll.ch, david@gibson.dropbear.id.au, galpress@amazon.com, hch@lst.de, jack@suse.cz, jannh@google.com, jgg@ziepe.ca, kirill@shutemov.name, ktkhai@virtuozzo.com, linmiaohe@huawei.com, linux-graphics-maintainer@vmware.com, linux-mm@kvack.org, mike.kravetz@oracle.com, mm-commits@vger.kernel.org, peterx@redhat.com, rppt@linux.vnet.ibm.com, sroland@vmware.com, torvalds@linux-foundation.org, willy@infradead.org, wzam@amazon.com Subject: [patch 07/29] hugetlb: break earlier in add_reservation_in_range() when we can Message-ID: <20210313050722.nUfetTcPM%akpm@linux-foundation.org> In-Reply-To: <20210312210632.9b7d62973d72a56fb13c7a03@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Peter Xu Subject: hugetlb: break earlier in add_reservation_in_range() when we can 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. Link: https://lkml.kernel.org/r/20210217233547.93892-3-peterx@redhat.com Signed-off-by: Peter Xu Reviewed-by: Mike Kravetz Reviewed-by: Miaohe Lin Cc: Alexey Dobriyan Cc: Andrea Arcangeli Cc: Christoph Hellwig Cc: Daniel Vetter Cc: David Airlie Cc: David Gibson Cc: Gal Pressman Cc: Jan Kara Cc: Jann Horn Cc: Jason Gunthorpe Cc: Kirill Shutemov Cc: Kirill Tkhai Cc: Matthew Wilcox Cc: Mike Rapoport Cc: Roland Scheidegger Cc: VMware Graphics Cc: Wei Zhang Signed-off-by: Andrew Morton --- mm/hugetlb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/hugetlb.c~hugetlg-break-earlier-in-add_reservation_in_range-when-we-can +++ a/mm/hugetlb.c @@ -387,7 +387,7 @@ static long add_reservation_in_range(str /* 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 _