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=-16.5 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 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 80566C432BE for ; Wed, 11 Aug 2021 20:36:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 633AE6101D for ; Wed, 11 Aug 2021 20:36:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232034AbhHKUhG (ORCPT ); Wed, 11 Aug 2021 16:37:06 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:32693 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231786AbhHKUhE (ORCPT ); Wed, 11 Aug 2021 16:37:04 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1628714200; 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=p6LHuy13nKs4bZicpGZZauB7ft7dST8UEGnG3gy9DN8=; b=CkGxclVG3pHshZRvoKuDO8pJhBY7TF7JPGOlVTxlFefLxaEkpJ76fW6eUIC9QpX5MWWYot bY0cMjAlMAtJoNV2031j8TI/3bfQb5A/FSYChGDFW/Ivd4SbGt9IzB97DoOFxienL4HwvX Mp8K9u4Ob2bOq552K90cZhayDV32Skw= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-592-QSB5eX08MEuIOl7_aCX0kQ-1; Wed, 11 Aug 2021 16:36:36 -0400 X-MC-Unique: QSB5eX08MEuIOl7_aCX0kQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 2BDEF8799EC; Wed, 11 Aug 2021 20:36:35 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.194.112]) by smtp.corp.redhat.com (Postfix) with ESMTP id 154021B46B; Wed, 11 Aug 2021 20:36:31 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: David Hildenbrand , Arnd Bergmann , Greg Kroah-Hartman , "Michael S. Tsirkin" , Jason Wang , "Rafael J. Wysocki" , Andrew Morton , Dan Williams , Hanjun Guo , Andy Shevchenko , virtualization@lists.linux-foundation.org, linux-mm@kvack.org Subject: [PATCH v1 3/3] kernel/resource: cleanup and optimize iomem_is_exclusive() Date: Wed, 11 Aug 2021 22:36:12 +0200 Message-Id: <20210811203612.138506-4-david@redhat.com> In-Reply-To: <20210811203612.138506-1-david@redhat.com> References: <20210811203612.138506-1-david@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Let's clean it up a bit, removing the unnecessary usage of r_next() by next_resource(), and use next_range_resource() in case we are not interested in a certain subtree. Signed-off-by: David Hildenbrand --- kernel/resource.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) diff --git a/kernel/resource.c b/kernel/resource.c index 2938cf520ca3..ea853a075a83 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -1754,9 +1754,8 @@ static int strict_iomem_checks; */ bool iomem_is_exclusive(u64 addr) { - struct resource *p = &iomem_resource; + struct resource *p; bool err = false; - loff_t l; int size = PAGE_SIZE; if (!strict_iomem_checks) @@ -1765,27 +1764,31 @@ bool iomem_is_exclusive(u64 addr) addr = addr & PAGE_MASK; read_lock(&resource_lock); - for (p = p->child; p ; p = r_next(NULL, p, &l)) { + for (p = iomem_resource.child; p ;) { /* * We can probably skip the resources without * IORESOURCE_IO attribute? */ if (p->start >= addr + size) break; - if (p->end < addr) + if (p->end < addr) { + /* No need to consider children */ + p = next_resource_skip_children(p); continue; + } + /* * A resource is exclusive if IORESOURCE_EXCLUSIVE is set * or CONFIG_IO_STRICT_DEVMEM is enabled and the * resource is busy. */ - if ((p->flags & IORESOURCE_BUSY) == 0) - continue; - if (IS_ENABLED(CONFIG_IO_STRICT_DEVMEM) - || p->flags & IORESOURCE_EXCLUSIVE) { + if (p->flags & IORESOURCE_BUSY && + (IS_ENABLED(CONFIG_IO_STRICT_DEVMEM) || + p->flags & IORESOURCE_EXCLUSIVE)) { err = true; break; } + p = next_resource(p); } read_unlock(&resource_lock); -- 2.31.1