From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754396Ab2HNI23 (ORCPT ); Tue, 14 Aug 2012 04:28:29 -0400 Received: from e28smtp04.in.ibm.com ([122.248.162.4]:40030 "EHLO e28smtp04.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753423Ab2HNI20 (ORCPT ); Tue, 14 Aug 2012 04:28:26 -0400 Message-ID: <502A0C19.6010007@linux.vnet.ibm.com> Date: Tue, 14 Aug 2012 13:58:09 +0530 From: "Srivatsa S. Bhat" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:14.0) Gecko/20120717 Thunderbird/14.0 MIME-Version: 1.0 To: Steven Rostedt CC: tglx@linutronix.de, mingo@kernel.org, paulmck@linux.vnet.ibm.com, josh@joshtriplett.org, linux-kernel@vger.kernel.org Subject: [PATCH] preempt/hardirq.h: Clarify PREEMPT_ACTIVE bit location References: <20120720192459.6149.14821.stgit@srivatsabhat.in.ibm.com> <1343706583.27983.28.camel@gandalf.stny.rr.com> In-Reply-To: <1343706583.27983.28.camel@gandalf.stny.rr.com> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit x-cbid: 12081408-5564-0000-0000-00000402DCA0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org By default, the PREEMPT_ACTIVE flag is bit 27, but different architectures can override that. Update the comment to reflect this fact. Signed-off-by: Srivatsa S. Bhat --- include/linux/hardirq.h | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-) diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h index 305f23c..483aa60 100644 --- a/include/linux/hardirq.h +++ b/include/linux/hardirq.h @@ -20,10 +20,15 @@ * hardirq nesting. An arch may choose to give less than 10 bits. * m68k expects it to be 8. * + * By default, the bits are defined as shown below: + * * - bits 16-25 are the hardirq count (max # of nested hardirqs: 1024) * - bit 26 is the NMI_MASK * - bit 27 is the PREEMPT_ACTIVE flag * + * However, different architectures may override them. (For example, + * x86 defines bit 28 as the PREEMPT_ACTIVE flag). + * * PREEMPT_MASK: 0x000000ff * SOFTIRQ_MASK: 0x0000ff00 * HARDIRQ_MASK: 0x03ff0000