From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 19 Aug 2001 15:01:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 19 Aug 2001 15:01:20 -0400 Received: from cpe.atm0-0-0-122182.bynxx2.customer.tele.dk ([62.243.2.100]:10592 "HELO marvin.athome.dk") by vger.kernel.org with SMTP id ; Sun, 19 Aug 2001 15:01:05 -0400 Message-ID: <3B800CF9.9000606@fugmann.dhs.org> Date: Sun, 19 Aug 2001 21:01:13 +0200 From: Anders Peter Fugmann User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.3) Gecko/20010801 X-Accept-Language: en-us MIME-Version: 1.0 To: chuckw@ieee.org Cc: linux-kernel@vger.kernel.org Subject: Re: Looking for comments on Bottom-Half/Tasklet/SoftIRQ In-Reply-To: <20010818231704.A2388@ieee.org> <3B7FF06A.4090606@fugmann.dhs.org> <20010819013508.B2388@ieee.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org chuckw@ieee.org wrote: > Thanks > > So, Bottom halves don't need to be re-entrant as do tasklets. SoftIRQ's > need to be re-entrant. The advantage of tasklets is that each tasklet can > be farmed out to different CPU's AND they don't need to be re-entrant > because only one instance is allowed at a time. I think I got it. That is 100% correct. > > Could you direct me to some code in the kernel which uses tasklets > so I can see the inner workings? Actually very few systems in the kernel has been rewritten to use tasklets instead og BH's. But as they are very simillar to BH's, you should be able to use the same thinking, its just a new API. Take a look at include/linux/interrupt.h (or http://lxr.linux.no/source/include/linux/interrupt.h, an invaluable source when coding for linux). Regards Anders Fugmann