Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933761AbZJIQGI (ORCPT ); Fri, 9 Oct 2009 12:06:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933741AbZJIQGH (ORCPT ); Fri, 9 Oct 2009 12:06:07 -0400 Received: from mtagate4.de.ibm.com ([195.212.17.164]:33091 "EHLO mtagate4.de.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933726AbZJIQGF (ORCPT ); Fri, 9 Oct 2009 12:06:05 -0400 From: Arnd Bergmann To: John Kacur Subject: Re: [PATCH RFC] BKL not necessary in cpuid_open Date: Fri, 9 Oct 2009 18:05:11 +0200 User-Agent: KMail/1.12.1 (Linux/2.6.31-11-generic; KDE/4.3.1; x86_64; ; ) Cc: tglx@linutronix.de, Ingo Molnar , linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org, Clark Williams References: In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <200910091805.11249.arnd@arndb.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 844 Lines: 22 On Wednesday 07 October 2009, John Kacur wrote: > > I've been staring at the BKL lock in cpuid_open, and I can't see what it > is protecting. However, I may have missed something - even something > obvious, so comments are welcome. > Hi John, In general, the lock_kernel() calls in any chardev open() file operation are the result of the BKL pushdown by Jon Corbet and others, which has happened some time last year[1]. I'd assume that the vast majority is not needed at all, so these are an easy target for removal. Arnd [1] http://lkml.indiana.edu/hypermail/linux/kernel/0805.2/0257.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/