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, 12 Sep 2001 06:59:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 12 Sep 2001 06:59:29 -0400 Received: from e1.ny.us.ibm.com ([32.97.182.101]:52942 "EHLO e1.ny.us.ibm.com") by vger.kernel.org with ESMTP id ; Wed, 12 Sep 2001 06:59:19 -0400 Date: Wed, 12 Sep 2001 16:34:26 +0530 From: Dipankar Sarma To: rusty@rustcorp.com.au Cc: Andrea Arcangeli , linux-kernel@vger.kernel.org, Paul Mckenney Subject: Re: 2.4.10pre7aa1 Message-ID: <20010912163426.A5979@in.ibm.com> Reply-To: dipankar@in.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org In article <20010912182440.3975719b.rusty@rustcorp.com.au> you wrote: > On Mon, 10 Sep 2001 17:54:17 +0200 > Andrea Arcangeli wrote: >> Only in 2.4.10pre7aa1: 00_rcu-1 >> >> wait_for_rcu and call_rcu implementation (from IBM). I did some >> modifications with respect to the original version from IBM. >> In particular I dropped the vmalloc_rcu/kmalloc_rcu, the >> rcu_head must always be allocated in the data structures, it has >> to be a field of a class, rather than hiding it in the allocation >> and playing dirty and risky with casts on a bigger allocation. > Hi Andrea, > Like the kernel threads approach, but AFAICT it won't work for the case of two CPUs running wait_for_rcu at the same time (on a 4-way or above). The patch I submitted to Andrea had logic to make sure that two CPUs don't execute wait_for_rcu() at the same time. Somehow it seems to have got lost in Andrea's modifications. I will look at that and submit a new patch to Andrea, if necessary. As for wrappers, I am agnostic. However, I think sooner or later people will start asking for them, if we go by our past experience. Thanks Dipankar -- Dipankar Sarma Project: http://lse.sourceforge.net Linux Technology Center, IBM Software Lab, Bangalore, India.