Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757336Ab2EKI3X (ORCPT ); Fri, 11 May 2012 04:29:23 -0400 Received: from mail7.hitachi.co.jp ([133.145.228.42]:33682 "EHLO mail7.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752152Ab2EKI3U (ORCPT ); Fri, 11 May 2012 04:29:20 -0400 X-AuditID: b753bd60-942caba000000f4e-20-4faccddc39e5 X-AuditID: b753bd60-942caba000000f4e-20-4faccddc39e5 Message-ID: <4FACCDDB.4080801@hitachi.com> Date: Fri, 11 May 2012 17:29:15 +0900 From: Masami Hiramatsu Organization: Hitachi, Ltd., Japan User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:12.0) Gecko/20120428 Thunderbird/12.0.1 MIME-Version: 1.0 To: Masami Hiramatsu Cc: Steven Rostedt , "Frank Ch. Eigler" , linux-kernel@vger.kernel.org, Ingo Molnar , Andrew Morton , Frederic Weisbecker , "H. Peter Anvin" , yrl.pp-manager.tt@hitachi.com Subject: Re: [RFC PATCH -tip ] x86/kprobes: kprobes call optimization References: <4FAA32B3.3070806@hitachi.com> <20120510115401.18125.93504.stgit@localhost.localdomain> In-Reply-To: <20120510115401.18125.93504.stgit@localhost.localdomain> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Brightmail-Tracker: AAAAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 823 Lines: 23 (2012/05/10 20:54), Masami Hiramatsu wrote: > Note: this code is still under development, but it will > be useful for the discussion to show this. > > Use relative call instead of relative jump for optimizing > kprobes. This reduces x86-depend magic code and runtime > memory size. Hmm, I've found that this patch may increase the execution time of probing more than 20%. I think that is more than acceptable... -- Masami HIRAMATSU Software Platform Research Dept. Linux Technology Center Hitachi, Ltd., Yokohama Research 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/