Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936373AbcJ0Nu6 (ORCPT ); Thu, 27 Oct 2016 09:50:58 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:52312 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S936274AbcJ0Nuy (ORCPT ); Thu, 27 Oct 2016 09:50:54 -0400 Date: Thu, 27 Oct 2016 10:37:14 +0200 From: Peter Zijlstra To: Arnaldo Carvalho de Melo Cc: Alexis Berlemont , linux-kernel@vger.kernel.org, mingo@redhat.com, alexander.shishkin@linux.intel.com Subject: Re: [PATCH 1/2] perf, x86-mm: Add exit-fault tracing Message-ID: <20161027083714.GF3568@worktop.programming.kicks-ass.net> References: <20161025235200.28781-1-alexis.berlemont@gmail.com> <20161025235200.28781-2-alexis.berlemont@gmail.com> <20161026085116.GZ3102@twins.programming.kicks-ass.net> <20161026185339.GC4704@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161026185339.GC4704@kernel.org> User-Agent: Mutt/1.5.22.1 (2013-10-16) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 778 Lines: 20 On Wed, Oct 26, 2016 at 04:53:39PM -0200, Arnaldo Carvalho de Melo wrote: > > > +++ b/arch/x86/mm/fault.c > > > @@ -1488,6 +1488,7 @@ trace_do_page_fault(struct pt_regs *regs, unsigned long error_code) > > > prev_state = exception_enter(); > > > trace_page_fault_entries(address, regs, error_code); > > > __do_page_fault(regs, error_code, address); > > > + trace_page_fault_exit(address); > > > > Aside from my general hatred of tracepoint, it bugs me that its not > > symmetric like the irq vector ones. But I'll leave that to x86 people. > > What is the simmetry problem, you think we should have: Look at arch/x86/include/asm/trace/irq_vectors.h and $ git grep "trace.*_VECTOR" The entry and exit tracepoints are fully symmetric and generate from a single macro.