From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752197Ab0EXF1o (ORCPT ); Mon, 24 May 2010 01:27:44 -0400 Received: from ozlabs.org ([203.10.76.45]:56564 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751360Ab0EXF1l (ORCPT ); Mon, 24 May 2010 01:27:41 -0400 Date: Mon, 24 May 2010 14:29:58 +1000 From: Paul Mackerras To: Peter Zijlstra Cc: Ingo Molnar , Arnaldo Carvalho de Melo , Frederic Weisbecker , Steven Rostedt , LKML Subject: Re: [PATCH 01/10] perf, trace: Remove IRQ-disable from perf/tracepoint interaction Message-ID: <20100524042958.GA10628@drongo> References: <20100521090201.326791353@chello.nl> <20100521090710.419716197@chello.nl> <20100523121159.GB3194@brick.ozlabs.ibm.com> <1274638587.1674.1729.camel@laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1274638587.1674.1729.camel@laptop> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, May 23, 2010 at 08:16:27PM +0200, Peter Zijlstra wrote: > On Sun, 2010-05-23 at 22:11 +1000, Paul Mackerras wrote: > > This is breaking on powerpc -- we don't have a "flags" element in > > struct pt_regs. What is it trying to do? Get the interrupt enable > > state, as local_irq_save(flags) would provide? > > Yes, I fouled that up. > > On x86 perf_arch_fetch_caller_regs() stores pt_regs::flags, which is the > same as used in local_save_flags(). > > So to avoid another local_save_flags() for the ftrace code, I wanted to > reuse it, and totally forgot the !x86 side of things. > > Possibly we could remove the local_save_flags() from the > perf_arch_fetch_caller_regs() as I'm not sure we actually use > pt_regs::flags (Frederic?) and leave the ftrace thing to use > local_save_flags(). > > Something like: Yes, that works -- at least, it compiles and seems to run. :) Acked-by: Paul Mackerras Paul.