From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 18790 invoked by alias); 16 Jul 2011 10:27:32 -0000 Received: (qmail 18782 invoked by uid 22791); 16 Jul 2011 10:27:31 -0000 X-SWARE-Spam-Status: No, hits=3.1 required=5.0 tests=AWL,BAYES_50,FREEMAIL_FROM,RCVD_IN_DNSWL_NONE,RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from smtp01.smtpout.orange.fr (HELO smtp.smtpout.orange.fr) (80.12.242.123) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Sat, 16 Jul 2011 10:27:13 +0000 Received: from sonybiranques ([90.48.205.253]) by mwinf5d48 with ME id 8aTB1h0035UZLoS03aTBlW; Sat, 16 Jul 2011 12:27:11 +0200 X-ME-engine: default From: "Pierre-Marie Boyer" To: Date: Sat, 16 Jul 2011 10:27:00 -0000 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact ecos-discuss-help@ecos.sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: ecos-discuss-owner@ecos.sourceware.org Subject: [ECOS] data access fron an interrupt handler X-SW-Source: 2011-07/txt/msg00029.txt.bz2 Hi, I plane to work with eCos : Install eCos kernel on a card with a LPC2106 uC from a PC linux station, and make some tests. But before this, I would like to know how interrupts handlers work exactly in case of multitasking software : My problem is about the globals variables access from within an interrupt function of a particular task. So, if the system work with several tasks. If in a task we have installed an interrupt handler (ex:harware interrupt). When the software is running, if this interrupt is launched by the hardware while another task is running, what happen if in this interrupt we want accessing (read or write) a global data of his task while this is not the same task suspended by the interrupt ? Because in this case the task context is not the same, and I think that no changing context is performed by the OS before running the interrupt. I think this can be a problem when we are in virtual memory system (uC with MMU ). Could you give me some information? (I know this is not a specific question of eCos, but I have not found were to ask this question. sory, and thank you in advance) -- Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss