From owner-freebsd-current@FreeBSD.ORG Mon Aug 30 10:21:25 2010 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id E45C41065673; Mon, 30 Aug 2010 10:21:25 +0000 (UTC) (envelope-from mavbsd@gmail.com) Received: from mail-fx0-f54.google.com (mail-fx0-f54.google.com [209.85.161.54]) by mx1.freebsd.org (Postfix) with ESMTP id 46AC98FC14; Mon, 30 Aug 2010 10:21:24 +0000 (UTC) Received: by fxm4 with SMTP id 4so3599562fxm.13 for ; Mon, 30 Aug 2010 03:21:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:sender:message-id:date:from :user-agent:mime-version:to:cc:subject:references:in-reply-to :x-enigmail-version:content-type:content-transfer-encoding; bh=828KnruxyHb9lw34XQxOUZnwvWiT7/GdosKhV6xUxyo=; b=tj36hg7Jdf7lYNS7hqlPECE16cB8HQd549nvbF1dTlsEJVA8E69TOEJGqnk4fqG+B1 ymrt86NsXr5qb5hgA5fHo6W/rhdEil+mqlB2aWtTVatxU1aBi7Z/m/E2jA0N5TZ98Nwn 1Pn35jHDKblwHMY7Tleq2wSAdyy4xiDn7P4HI= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:x-enigmail-version:content-type :content-transfer-encoding; b=DjFML9cJP03R0botZpzeUzERJ7zNa1fOubV33sXmBc1JtF1CgoFI6SSjt3lkSf4oEt tAcJas6bv+cPajrPJ+4V/yAOdQrJZYFCF9dD94lzisGYB47EVg9kmxP6yh1f5J0j0iG3 jrHbWarl4YNdFEFZnJsjdiNYdbrjnq6TGTPBY= Received: by 10.223.119.203 with SMTP id a11mr3569856far.42.1283163684102; Mon, 30 Aug 2010 03:21:24 -0700 (PDT) Received: from mavbook2.mavhome.dp.ua (pc.mavhome.dp.ua [212.86.226.226]) by mx.google.com with ESMTPS id b9sm3234577faq.7.2010.08.30.03.21.22 (version=SSLv3 cipher=RC4-MD5); Mon, 30 Aug 2010 03:21:23 -0700 (PDT) Sender: Alexander Motin Message-ID: <4C7B861D.2050304@FreeBSD.org> Date: Mon, 30 Aug 2010 13:21:17 +0300 From: Alexander Motin User-Agent: Thunderbird 2.0.0.23 (X11/20091212) MIME-Version: 1.0 To: gljennjohn@googlemail.com References: <4C7A5C28.1090904@FreeBSD.org> <20100830110932.23425932@ernst.jennejohn.org> <4C7B82EA.2040104@FreeBSD.org> <20100830121148.11926306@ernst.jennejohn.org> In-Reply-To: <20100830121148.11926306@ernst.jennejohn.org> X-Enigmail-Version: 0.96.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: freebsd-hackers@freebsd.org, FreeBSD-Current Subject: Re: One-shot-oriented event timers management X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 30 Aug 2010 10:21:26 -0000 Gary Jennejohn wrote: > On Mon, 30 Aug 2010 13:07:38 +0300 > Alexander Motin wrote: >> Gary Jennejohn wrote: >>> Ah, I think I see it now. My desktop has only C1 enabled. Is that it? >>> Unfortunately, it appears that only C1 is supported :( >> Yes, as I have said, at this moment empty ticks skipped only while CPU >> is in C2/C3 states. In C1 state there is no way to handle lost events on >> wake up. While it may be not very dangerous, it is not very good. > > Too bad. I'd say that systems which are limited to C1 don't benefit > much (or not at all) from your changes. For this moment - indeed not much. As I have said, feature with skipping ticks is on early development stage. I've just implemented it in most straightforward way, abusing feature provided by ACPI. To benefit other systems and platforms, more tight integration with interrupt, callout and possibly scheduler subsystem will be needed. -- Alexander Motin