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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C9327C6FA90 for ; Tue, 27 Sep 2022 07:53:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230335AbiI0HxV (ORCPT ); Tue, 27 Sep 2022 03:53:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60262 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231239AbiI0HxR (ORCPT ); Tue, 27 Sep 2022 03:53:17 -0400 Received: from out0.migadu.com (out0.migadu.com [IPv6:2001:41d0:2:267::]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8ABAFAB42A for ; Tue, 27 Sep 2022 00:53:14 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1664265192; 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; bh=QARHQJJqXFRMVlOzDzMQADfn54pG19eVVGeo/uHoR54=; b=mwS5stQ5zKqAEvrTnAEnNq2aehk18zEWWgwhz4mJvHGsxxyN7AQuOyAIBbQYedA19wZOFl WotowCGn46UDCjOZj8wXkdxxX+xhMBo3WImju8ItTznhseB0gKLqmlv3IR+06f6JnVAc+f ueOL+nTj+IXmt0Bfu+aQ9wyLmLi3pMk= From: Yajun Deng To: akpm@linux-foundation.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Yajun Deng Subject: [PATCH] mm/early_ioremap: Combine two loops to improve performance Date: Tue, 27 Sep 2022 15:52:39 +0800 Message-Id: <20220927075239.270583-1-yajun.deng@linux.dev> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The first loop will waring once if prev_map is init, we can add a boolean variable to do that. So those two loops can be combined to improve performance. Signed-off-by: Yajun Deng --- mm/early_ioremap.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/mm/early_ioremap.c b/mm/early_ioremap.c index 9bc12e526ed0..3076fb47c685 100644 --- a/mm/early_ioremap.c +++ b/mm/early_ioremap.c @@ -70,14 +70,15 @@ static unsigned long slot_virt[FIX_BTMAPS_SLOTS] __initdata; void __init early_ioremap_setup(void) { + bool init_prev_map = false; int i; - for (i = 0; i < FIX_BTMAPS_SLOTS; i++) - if (WARN_ON(prev_map[i])) - break; + for (i = 0; i < FIX_BTMAPS_SLOTS; i++) { + if (!init_prev_map && WARN_ON(prev_map[i])) + init_prev_map = true; - for (i = 0; i < FIX_BTMAPS_SLOTS; i++) slot_virt[i] = __fix_to_virt(FIX_BTMAP_BEGIN - NR_FIX_BTMAPS*i); + } } static int __init check_early_ioremap_leak(void) -- 2.25.1