Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750868AbVIQOcT (ORCPT ); Sat, 17 Sep 2005 10:32:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750872AbVIQOcS (ORCPT ); Sat, 17 Sep 2005 10:32:18 -0400 Received: from ozlabs.org ([203.10.76.45]:34182 "EHLO ozlabs.org") by vger.kernel.org with ESMTP id S1750848AbVIQOcS (ORCPT ); Sat, 17 Sep 2005 10:32:18 -0400 Date: Sun, 18 Sep 2005 00:32:05 +1000 From: Anton Blanchard To: Tejun Heo Cc: lkml Subject: Re: [QUESTION] The cost of local interrupt enable/disable Message-ID: <20050917143204.GA17639@krispykreme> References: <432C2169.2090300@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <432C2169.2090300@gmail.com> User-Agent: Mutt/1.5.10i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 700 Lines: 18 Hi, > I'm curious about the cost of local_irq_enable/disable()'s on various > architectures. I found a freebsd discussion thread by googling which > says that each takes 3 cycles on i386 (very cheap), but for Pentium4, > people are talking in the order of several hundreds cycles. Are these > correct? How about other architectures? It varies on ppc64, but its in the order of 10s of cycles. 40-50 cycles is probably a decent estimation. Anton - 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/