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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 7357FC43603 for ; Wed, 11 Dec 2019 15:35:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3B3D12077B for ; Wed, 11 Dec 2019 15:35:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576078528; bh=szGZa6xdAAZUKRQe07yyEdszF/EljzEkg2z0kvziHNQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=EON/OHscbeLKM6M0XyxSqobQqPLN9QkeXt75UfwO3Q50h/sP1FaTwt83f0tGsdysP Y42u+7/zDANqtGNJrsV2lKUu75nQhY0uiymsHOCRFzHZYd239UEpSBKPu44ObDiQe3 IlbmHJqIxqV613CyeA3QQ+knrqr6YZmkIoIK3Lb4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388147AbfLKPf1 (ORCPT ); Wed, 11 Dec 2019 10:35:27 -0500 Received: from mail.kernel.org ([198.145.29.99]:44216 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388121AbfLKPfV (ORCPT ); Wed, 11 Dec 2019 10:35:21 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A2CE324656; Wed, 11 Dec 2019 15:35:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576078521; bh=szGZa6xdAAZUKRQe07yyEdszF/EljzEkg2z0kvziHNQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bO8GBJ4udQ9HrzoCA5CAXNCBVxm/ZQGYQIJYvRNJ1YRScNS/1hghYTKBAQUwOm7Yl 20MA5VZUy/x7SmZzVLNFgoRa/ZDAWvT3tOXJWp2M9eG6+Xoo/A7nOqLEwfs+LWz8KE y4ejzTRk8xswfFB1d41RXGkb0ob8BUHFyeO7+KQc= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Eric Dumazet , Corentin Labbe , Christoph Hellwig , Marek Szyprowski , Sasha Levin Subject: [PATCH AUTOSEL 4.9 10/42] dma-debug: add a schedule point in debug_dma_dump_mappings() Date: Wed, 11 Dec 2019 10:34:38 -0500 Message-Id: <20191211153510.23861-10-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191211153510.23861-1-sashal@kernel.org> References: <20191211153510.23861-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric Dumazet [ Upstream commit 9ff6aa027dbb98755f0265695354f2dd07c0d1ce ] debug_dma_dump_mappings() can take a lot of cpu cycles : lpk43:/# time wc -l /sys/kernel/debug/dma-api/dump 163435 /sys/kernel/debug/dma-api/dump real 0m0.463s user 0m0.003s sys 0m0.459s Let's add a cond_resched() to avoid holding cpu for too long. Signed-off-by: Eric Dumazet Cc: Corentin Labbe Cc: Christoph Hellwig Cc: Marek Szyprowski Signed-off-by: Christoph Hellwig Signed-off-by: Sasha Levin --- lib/dma-debug.c | 1 + 1 file changed, 1 insertion(+) diff --git a/lib/dma-debug.c b/lib/dma-debug.c index 8971370bfb161..4435bec55fb59 100644 --- a/lib/dma-debug.c +++ b/lib/dma-debug.c @@ -435,6 +435,7 @@ void debug_dma_dump_mappings(struct device *dev) } spin_unlock_irqrestore(&bucket->lock, flags); + cond_resched(); } } EXPORT_SYMBOL(debug_dma_dump_mappings); -- 2.20.1