From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 20 Jun 2001 12:43:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 20 Jun 2001 12:43:04 -0400 Received: from gateway-1237.mvista.com ([12.44.186.158]:39922 "EHLO hermes.mvista.com") by vger.kernel.org with ESMTP id ; Wed, 20 Jun 2001 12:43:02 -0400 Message-ID: <3B30D1AC.325A4CCB@mvista.com> Date: Wed, 20 Jun 2001 09:39:08 -0700 From: george anzinger Organization: Monta Vista Software X-Mailer: Mozilla 4.77 [en] (X11; U; Linux 2.2.12-20b i686) X-Accept-Language: en MIME-Version: 1.0 To: Alexander Viro CC: Jes Sorensen , Alan Cox , bert hubert , "linux-kernel@vger.kernel.org" Subject: Re: Alan Cox quote? (was: Re: accounting for threads) In-Reply-To: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Alexander Viro wrote: > > On 20 Jun 2001, Jes Sorensen wrote: > > > Not to mention how complex it is to get locking right in an efficient > > manner. Programming threads is not that much different from kernel SMP > > programming, except that in userland you get a core dump and retry, in > > the kernel you get an OOPS and an fsck and retry. > > Arrgh. As long as we have that "SMP makes locking harder" myth floating > around we _will_ get problems. Kernel UP programming is not different > from SMP one. It is multithreaded. And amount of genuine SMP bugs is > very small compared to ones that had been there on UP since way back. > And yes, programming threads is the same thing. No arguments here. > Correct, IF the UP kernel is preemptable. As long as it is not (and SMP is ignored) threads are harder BECAUSE they are preemptable. George