From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 12398 invoked by alias); 14 Sep 2006 15:15:41 -0000 Received: (qmail 12382 invoked by uid 22791); 14 Sep 2006 15:15:36 -0000 X-Spam-Check-By: sourceware.org Received: from snape.ecoscentric.com (HELO snape.ecoscentric.com) (212.13.207.199) by sourceware.org (qpsmtpd/0.31) with ESMTP; Thu, 14 Sep 2006 15:15:32 +0000 Received: from localhost (localhost [127.0.0.1]) by snape.ecoscentric.com (Postfix) with ESMTP id 6E920C54021; Thu, 14 Sep 2006 16:15:28 +0100 (BST) Received: from snape.ecoscentric.com ([127.0.0.1]) by localhost (snape.ecoscentric.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id akF6fRpt0tqC; Thu, 14 Sep 2006 16:15:26 +0100 (BST) Received: from delenn.bartv.net (snape.ecoscentric.com [212.13.207.199]) by snape.ecoscentric.com (Postfix) with ESMTP id F3A47C54020; Thu, 14 Sep 2006 16:15:25 +0100 (BST) Date: Thu, 14 Sep 2006 15:15:00 -0000 Message-Id: To: zankl@decomsys.com CC: ecos-discuss@sources.redhat.com In-reply-to: <0F0005CE495E094A96B04D78F24E5A7F3858B5@mana.decomsys.com> (zankl@decomsys.com) From: Bart Veer References: <0F0005CE495E094A96B04D78F24E5A7F3858B5@mana.decomsys.com> Mailing-List: contact ecos-discuss-help@ecos.sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: ecos-discuss-owner@ecos.sourceware.org Subject: Re: [ECOS] JFFS2 Access and interrupts X-SW-Source: 2006-09/txt/msg00096.txt.bz2 >>>>> "Gernot" == Gernot Zankl writes: >> > FYI I finally found the/our bug, causing the application to >> > corrupt the jffs2. We just used the wrong block size in >> > the configuration of the underlying flash driver, causing to >> > erase too much flash memory (and destroying still active inodes). >> >> FAOD - it had *nothing* to do with interrupts during FLASH operations? Gernot> At least not in "our" version of the flash driver (v1) Gernot> which has been provided and modified by Analogue&Micro, Gernot> where all calls to the critical functions are guarded by Gernot> the HAL_DISABLE_INTERRUPTS and HAL_RESTORES_INTERRUPTS Gernot> macros. Of course that approach gives you an interrupt latency of somewhere from several 100 milliseconds up to 5 seconds, depending on the exact flash hardware and the environmental conditions. That is the time needed to erase a whole flash sector. So any time you perform jffs2 file I/O your application may become completely unresponsive to all external events for a number of seconds. It depends on the application whether or not such behaviour is acceptable. Bart -- Bart Veer eCos Configuration Architect http://www.ecoscentric.com/ The eCos and RedBoot experts -- Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss