From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751888AbdBOHLd (ORCPT ); Wed, 15 Feb 2017 02:11:33 -0500 Received: from mail.kernel.org ([198.145.29.136]:59022 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751768AbdBOHLc (ORCPT ); Wed, 15 Feb 2017 02:11:32 -0500 Date: Wed, 15 Feb 2017 16:11:26 +0900 From: Masami Hiramatsu To: "Naveen N. Rao" Cc: Ananth N Mavinakayanahalli , Michael Ellerman , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH 1/3] powerpc: kprobes: add support for KPROBES_ON_FTRACE Message-Id: <20170215161126.104c1db721182e1e75244125@kernel.org> In-Reply-To: <1cc8a5580ae3a642fea137b7fe9c526402d4af33.1487098440.git.naveen.n.rao@linux.vnet.ibm.com> References: <1cc8a5580ae3a642fea137b7fe9c526402d4af33.1487098440.git.naveen.n.rao@linux.vnet.ibm.com> X-Mailer: Sylpheed 3.5.0 (GTK+ 2.24.30; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Naveen, On Wed, 15 Feb 2017 00:28:34 +0530 "Naveen N. Rao" wrote: > diff --git a/arch/powerpc/kernel/optprobes.c b/arch/powerpc/kernel/optprobes.c > index e51a045f3d3b..a8f414a0b141 100644 > --- a/arch/powerpc/kernel/optprobes.c > +++ b/arch/powerpc/kernel/optprobes.c > @@ -70,6 +70,9 @@ static unsigned long can_optimize(struct kprobe *p) > struct instruction_op op; > unsigned long nip = 0; > > + if (unlikely(kprobe_ftrace(p))) > + return 0; > + Hmm, this should not be checked in arch-depend code, since it may duplicate code in each arch. Please try below. Thanks, commit 897bb304974c1b0c19a4274fea220b175b07f353 Author: Masami Hiramatsu Date: Wed Feb 15 15:48:14 2017 +0900 kprobes: Skip preparing optprobe if the probe is ftrace-based Skip preparing optprobe if the probe is ftrace-based, since anyway, it must not be optimized (or already optimized by ftrace). Signed-off-by: Masami Hiramatsu diff --git a/kernel/kprobes.c b/kernel/kprobes.c index ebb4dad..546a8b1 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -746,13 +746,20 @@ static void kill_optimized_kprobe(struct kprobe *p) arch_remove_optimized_kprobe(op); } +static inline +void __prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p) +{ + if (!kprobe_ftrace(p)) + arch_prepare_optimized_kprobe(op, p); +} + /* Try to prepare optimized instructions */ static void prepare_optimized_kprobe(struct kprobe *p) { struct optimized_kprobe *op; op = container_of(p, struct optimized_kprobe, kp); - arch_prepare_optimized_kprobe(op, p); + __prepare_optimized_kprobe(op, p); } /* Allocate new optimized_kprobe and try to prepare optimized instructions */ @@ -766,7 +773,7 @@ static struct kprobe *alloc_aggr_kprobe(struct kprobe *p) INIT_LIST_HEAD(&op->list); op->kp.addr = p->addr; - arch_prepare_optimized_kprobe(op, p); + __prepare_optimized_kprobe(op, p); return &op->kp; } -- Masami Hiramatsu