Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756287AbcCWRue (ORCPT ); Wed, 23 Mar 2016 13:50:34 -0400 Received: from casper.infradead.org ([85.118.1.10]:57397 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752843AbcCWRuc (ORCPT ); Wed, 23 Mar 2016 13:50:32 -0400 Date: Wed, 23 Mar 2016 18:50:21 +0100 From: Peter Zijlstra To: Wang Nan Cc: mingo@redhat.com, linux-kernel@vger.kernel.org, He Kuang , Alexei Starovoitov , Arnaldo Carvalho de Melo , Brendan Gregg , Jiri Olsa , Masami Hiramatsu , Namhyung Kim , Zefan Li , pi3orama@163.com, Will Deacon Subject: Re: [PATCH 2/5] perf core: Set event's default overflow_handler Message-ID: <20160323175021.GK6356@twins.programming.kicks-ass.net> References: <1457949585-191064-1-git-send-email-wangnan0@huawei.com> <1457949585-191064-3-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1457949585-191064-3-git-send-email-wangnan0@huawei.com> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1594 Lines: 44 On Mon, Mar 14, 2016 at 09:59:42AM +0000, Wang Nan wrote: > +++ b/arch/arm/kernel/hw_breakpoint.c > @@ -631,7 +631,7 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp) > info->address &= ~alignment_mask; > info->ctrl.len <<= offset; > > - if (!bp->overflow_handler) { > + if (is_default_overflow_handler(bp)) { > /* > * Mismatch breakpoints are required for single-stepping > * breakpoints. > @@ -754,7 +754,7 @@ static void watchpoint_handler(unsigned long addr, unsigned int fsr, > * mismatch breakpoint so we can single-step over the > * watchpoint trigger. > */ > - if (!wp->overflow_handler) > + if (is_default_overflow_handler(wp)) > enable_single_step(wp, instruction_pointer(regs)); > > unlock: > diff --git a/arch/arm64/kernel/hw_breakpoint.c b/arch/arm64/kernel/hw_breakpoint.c > index b45c95d..4ef5373 100644 > --- a/arch/arm64/kernel/hw_breakpoint.c > +++ b/arch/arm64/kernel/hw_breakpoint.c > @@ -616,7 +616,7 @@ static int breakpoint_handler(unsigned long unused, unsigned int esr, > perf_bp_event(bp, regs); > > /* Do we need to handle the stepping? */ > - if (!bp->overflow_handler) > + if (is_default_overflow_handler(bp)) > step = 1; > unlock: > rcu_read_unlock(); > @@ -712,7 +712,7 @@ static int watchpoint_handler(unsigned long addr, unsigned int esr, > perf_bp_event(wp, regs); > > /* Do we need to handle the stepping? */ > - if (!wp->overflow_handler) > + if (is_default_overflow_handler(wp)) > step = 1; > > unlock: Will, why does it matter what the overflow handler is for this stuff?