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=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 13AB9C43603 for ; Wed, 11 Dec 2019 15:45:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CC07C208C3 for ; Wed, 11 Dec 2019 15:45:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576079115; bh=o+OfEXRo/CR/7nckr17Av4sSDFLQaNkT8OLm8QIYyaY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=WgFpUOYtXXMzu2uqH+m6q1myYfCOAN8tpglJxjsRv9t2XO9d4QiNSWTRuDYoyO2jU 41d9lbtP1Iktv1BYBfTn1ADvxj7sYhrkLSsLALs98bj+M8pKaCdllMr0p+UbY0RVGf CLwkll6brxxCWhF+j6GL4gL34cAZwH4nimSiPXEo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733263AbfLKP1L (ORCPT ); Wed, 11 Dec 2019 10:27:11 -0500 Received: from mail.kernel.org ([198.145.29.99]:60618 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732726AbfLKP1C (ORCPT ); Wed, 11 Dec 2019 10:27:02 -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 D54E424658; Wed, 11 Dec 2019 15:27:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576078021; bh=o+OfEXRo/CR/7nckr17Av4sSDFLQaNkT8OLm8QIYyaY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CBHtWxA0WYuVFEhqqqIxl4hhLao6Wza0vgKn1jiaaj8SZBA0gjNfd2cyw0ZnaTsM1 6upFCMWfWFV+eihvtjvL18pttR0eCjIRY17N2ZqGFSWh1+YPsHU3MClGyQvCWeoHRb d31s7bG8636ld8uaVbiqIUcvB1fxKe3HCQb4DsVE= 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 4.19 16/79] dma-debug: add a schedule point in debug_dma_dump_mappings() Date: Wed, 11 Dec 2019 10:25:40 -0500 Message-Id: <20191211152643.23056-16-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191211152643.23056-1-sashal@kernel.org> References: <20191211152643.23056-1-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 --- kernel/dma/debug.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c index c007d25bee098..3a2397444076e 100644 --- a/kernel/dma/debug.c +++ b/kernel/dma/debug.c @@ -442,6 +442,7 @@ void debug_dma_dump_mappings(struct device *dev) } spin_unlock_irqrestore(&bucket->lock, flags); + cond_resched(); } } -- 2.20.1