Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754136Ab0KZJ1z (ORCPT ); Fri, 26 Nov 2010 04:27:55 -0500 Received: from mail4.hitachi.co.jp ([133.145.228.5]:33206 "EHLO mail4.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751902Ab0KZJ1x (ORCPT ); Fri, 26 Nov 2010 04:27:53 -0500 X-AuditID: b753bd60-a4ba2ba000003e7d-df-4cef7d9573aa Message-ID: <4CEF7D92.1080207@hitachi.com> Date: Fri, 26 Nov 2010 18:27:46 +0900 From: Masami Hiramatsu Organization: Systems Development Lab., Hitachi, Ltd., Japan User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; ja; rv:1.9.2.12) Gecko/20101027 Thunderbird/3.1.6 MIME-Version: 1.0 To: Ingo Molnar Cc: Rusty Russell , Frederic Weisbecker , Ananth N Mavinakayanahalli , Jason Baron , Mathieu Desnoyers , linux-kernel@vger.kernel.org, 2nddept-manager@sdl.hitachi.co.jp, Masami Hiramatsu , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, Peter Zijlstra , Steven Rostedt Subject: Re: [PATCH -tip v4 3/3] kprobes: Support delayed unoptimization References: <20101119100925.16882.34772.stgit@ltc236.sdl.hitachi.co.jp> <20101119100948.16882.24259.stgit@ltc236.sdl.hitachi.co.jp> <20101126072621.GB19589@elte.hu> In-Reply-To: <20101126072621.GB19589@elte.hu> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Brightmail-Tracker: AAAAAA== X-FMFTCR: RANGEA Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2063 Lines: 55 (2010/11/26 16:26), Ingo Molnar wrote: > * Masami Hiramatsu wrote: > >> Unoptimization occurs when a probe is unregistered or disabled, and >> is heavy because it recovers instructions by using stop_machine(). >> This patch delays unoptimization operations and unoptimize several >> probes at once by using text_poke_smp_batch(). >> This can avoid unexpected system slowdown coming from stop_machine(). >> >> Changes in v2: >> - Use dynamic allocated buffers and params. >> >> Signed-off-by: Masami Hiramatsu >> Cc: Thomas Gleixner >> Cc: Ingo Molnar >> Cc: "H. Peter Anvin" >> Cc: x86@kernel.org >> Cc: Mathieu Desnoyers >> Cc: Peter Zijlstra >> Cc: Ananth N Mavinakayanahalli >> Cc: Steven Rostedt >> Cc: linux-kernel@vger.kernel.org >> Cc: Rusty Russell >> Cc: Frederic Weisbecker >> --- >> >> arch/x86/include/asm/kprobes.h | 4 >> arch/x86/kernel/kprobes.c | 45 ++++ >> include/linux/kprobes.h | 2 >> kernel/kprobes.c | 434 +++++++++++++++++++++++++++------------- >> 4 files changed, 344 insertions(+), 141 deletions(-) > > Hm, this is a scary big patch with non-trivial effects - it should be broken up as > much as possible, into successive, bisectable steps. The end result looks mostly > fine - it's just this one huge step of a patch that is dangerous. Agreed, then I'll break it down to several patches. Thank you for your comment! :) > > Thanks, > > Ingo -- Masami HIRAMATSU 2nd Dept. Linux Technology Center Hitachi, Ltd., Systems Development Laboratory E-mail: masami.hiramatsu.pt@hitachi.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/