Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751647AbZCJX4u (ORCPT ); Tue, 10 Mar 2009 19:56:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750930AbZCJX4j (ORCPT ); Tue, 10 Mar 2009 19:56:39 -0400 Received: from earthlight.etchedpixels.co.uk ([81.2.110.250]:53736 "EHLO www.etchedpixels.co.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750886AbZCJX4i (ORCPT ); Tue, 10 Mar 2009 19:56:38 -0400 Date: Tue, 10 Mar 2009 23:56:59 +0000 From: Alan Cox To: Robert Hancock Cc: "Altobelli, David" , Andrew Morton , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] tweak spin logic for hpilo Message-ID: <20090310235659.1fe62b2e@lxorguk.ukuu.org.uk> In-Reply-To: <49B6F9A9.1030803@gmail.com> References: <20090309225651.GA13702@ldl.fc.hp.com> <20090309160437.b71041d5.akpm@linux-foundation.org> <92D64232F2316045B18937D5C9996B1522834ABED6@GVW1144EXB.americas.hpqcorp.net> <49B6F9A9.1030803@gmail.com> X-Mailer: Claws Mail 3.7.0 (GTK+ 2.14.7; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 455 Lines: 10 > You're using udelay, which is a spin loop. Nothing else can happen on > that CPU while it's delaying anyway. However if your polling is doing I/O its clogging up the I/O busses (and quite often the bridge) -- 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/