Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752299Ab0HPDad (ORCPT ); Sun, 15 Aug 2010 23:30:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:17278 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751812Ab0HPDac (ORCPT ); Sun, 15 Aug 2010 23:30:32 -0400 Subject: Re: Intel graphics CPU usage - SDVO detect bogosity? From: Dave Airlie To: Linus Torvalds Cc: Dave Airlie , Chris Wilson , Zhao Yakui , Jesse Barnes , Adam Jackson , linux-kernel@vger.kernel.org, DRI mailing list In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Date: Mon, 16 Aug 2010 13:30:08 +1000 Message-ID: <1281929408.3530.1.camel@clockmaker-el6> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1073 Lines: 30 On Sun, 2010-08-15 at 19:32 -0700, Linus Torvalds wrote: > I started wondering why 'top' was showing an otherwise idle system as > having a load average of 0.5+, and worker threads constantly using the > CPU. > > So I did a system-wide profile, and got the attached output (look at > it in a really wide terminal). > > There seems to be something _seriously_ wrong with i915 SDVO detect. > This is on an Apple Mac Mini (hey, your favorite problem child!), and > apparently it spends 20% of its non-idle CPU time just doing udelay's > for the i2c SDVO connection detection. > > That sounds a bit wrong, doesn't it? At least we should replace mdelay with msleep in those functions. Can you get a boot with drm.debug=4? I wonder are we picking up a bad SDVO, the insane code retries 50 times with a hard loop delay. Dave. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/