Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752035AbbGIHeE (ORCPT ); Thu, 9 Jul 2015 03:34:04 -0400 Received: from cantor2.suse.de ([195.135.220.15]:52596 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751554AbbGIHd4 (ORCPT ); Thu, 9 Jul 2015 03:33:56 -0400 Message-ID: <1436427171.2530.5.camel@suse.com> Subject: Re: [PATCH 1/1] suspend: delete sys_sync() From: Oliver Neukum To: "Rafael J. Wysocki" Cc: Dave Chinner , Henrique de Moraes Holschuh , Len Brown , Len Brown , One Thousand Gnomes , Alan Stern , "linux-kernel@vger.kernel.org" , Linux PM list Date: Thu, 09 Jul 2015 09:32:51 +0200 In-Reply-To: <1850836.6zSgANe26P@vostro.rjw.lan> References: <4290667.ZqInAykFGS@vostro.rjw.lan> <1522789.fQO6RUUx40@vostro.rjw.lan> <1436341873.5636.5.camel@suse.com> <1850836.6zSgANe26P@vostro.rjw.lan> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.12.11 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 935 Lines: 30 On Thu, 2015-07-09 at 00:03 +0200, Rafael J. Wysocki wrote: > Nothing and I'm not discussing that (I've said that already at least once in > this thread). > > What I'm questioning is the "why" of calling sys_sync() from the kernel. That's strictly speaking two questions 1. Why do it in the kernel That is easy. It closes the window of a race condition. 2. Why do it at all In essence because the system becomes inactive. For example we say that data hits the disk after 30s maximum. We cannot meet such a limit unless we sync. There are additional issues, such as a system appearing inactive during suspension and frankly the far greater likelihood of a crash. Regards Oliver -- 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/