Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753574AbXHHKRQ (ORCPT ); Wed, 8 Aug 2007 06:17:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751888AbXHHKRB (ORCPT ); Wed, 8 Aug 2007 06:17:01 -0400 Received: from one.firstfloor.org ([213.235.205.2]:35976 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751045AbXHHKRB (ORCPT ); Wed, 8 Aug 2007 06:17:01 -0400 Date: Wed, 8 Aug 2007 12:17:00 +0200 From: Andi Kleen To: Lee Revell Cc: Andi Kleen , dragoran , linux-kernel@vger.kernel.org Subject: Re: allow non root users to set io priority "idle" ? Message-ID: <20070808101659.GB12861@one.firstfloor.org> References: <46B6EDCB.6030806@gmail.com> <75b66ecd0708071926s519ebcf5t680c2ed8ab7ead8e@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <75b66ecd0708071926s519ebcf5t680c2ed8ab7ead8e@mail.gmail.com> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 690 Lines: 18 > I don't think it's a problem for high priority (RT) tasks - it's well > known in the real time Linux community that you never, ever do IO from > a thread that has to satisfy RT constraints. The point here is to protect the system from a potentially malicious user > which I would > expect to take fewer locks. Even a single lock is one too much. My example lock -- the page lock bit -- certainly applies to both reads and writes. -Andi - 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/