From owner-cvs-src@FreeBSD.ORG Tue Aug 3 20:34:41 2004 Return-Path: Delivered-To: cvs-src@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 0207616A4CE; Tue, 3 Aug 2004 20:34:41 +0000 (GMT) Received: from ns1.xcllnt.net (209-128-86-226.bayarea.net [209.128.86.226]) by mx1.FreeBSD.org (Postfix) with ESMTP id 944C643D48; Tue, 3 Aug 2004 20:34:40 +0000 (GMT) (envelope-from marcel@xcllnt.net) Received: from ns1.xcllnt.net (localhost [127.0.0.1]) by ns1.xcllnt.net (8.12.11/8.12.11) with ESMTP id i73KYeM5000155; Tue, 3 Aug 2004 13:34:40 -0700 (PDT) (envelope-from marcel@ns1.xcllnt.net) Received: (from marcel@localhost) by ns1.xcllnt.net (8.12.11/8.12.11/Submit) id i73KYexn000154; Tue, 3 Aug 2004 13:34:40 -0700 (PDT) (envelope-from marcel) Date: Tue, 3 Aug 2004 13:34:40 -0700 From: Marcel Moolenaar To: Maxime Henrion Message-ID: <20040803203440.GA113@ns1.xcllnt.net> References: <200408031844.i73IiRb4082245@repoman.freebsd.org> <20040803191313.GB99599@ns1.xcllnt.net> <20040803202342.GH13608@elvis.mu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040803202342.GH13608@elvis.mu.org> User-Agent: Mutt/1.5.5.1i cc: cvs-src@freebsd.org cc: src-committers@freebsd.org cc: cvs-all@freebsd.org Subject: Re: cvs commit: src/sys/alpha/include cpu.h src/sys/amd64/include cpu.h src/sys/arm/include cpu.h src/sys/i386/include cpu.h src/sys/ia64/include cpu.h src/sys/powerpc/include cpu.h src/sys/sparc64/include cpu.h src/sys/kern kern_mutex.c X-BeenThere: cvs-src@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: CVS commit messages for the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 03 Aug 2004 20:34:41 -0000 On Tue, Aug 03, 2004 at 10:23:42PM +0200, Maxime Henrion wrote: > > > > Cool, but can you explain to me how exactly cpu_spinwait() is to be > > different from cpu_idle() that we cannot use cpu_idle()? > > They serve very different purposes. The cpu_spinwait() macro is used > on x86 and amd64 to insert a "pause" instruction before retrying to > obtain a spin mutex. It is supposed to improve performance on P4 and > newer machines. It is empty on other architectures because we don't > have such a thing, or at least it's not implemented. Ok, thanks. -- Marcel Moolenaar USPA: A-39004 marcel@xcllnt.net