From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_NEOMUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 04D2DC43441 for ; Fri, 9 Nov 2018 15:21:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C8DB520883 for ; Fri, 9 Nov 2018 15:21:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C8DB520883 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728287AbeKJBCo (ORCPT ); Fri, 9 Nov 2018 20:02:44 -0500 Received: from mx1.redhat.com ([209.132.183.28]:55412 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727800AbeKJBCo (ORCPT ); Fri, 9 Nov 2018 20:02:44 -0500 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id F077E3082142; Fri, 9 Nov 2018 15:21:42 +0000 (UTC) Received: from treble (ovpn-124-61.rdu2.redhat.com [10.10.124.61]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 310D810B034B; Fri, 9 Nov 2018 15:21:41 +0000 (UTC) Date: Fri, 9 Nov 2018 09:21:39 -0600 From: Josh Poimboeuf To: Andy Lutomirski Cc: Ingo Molnar , LKML , X86 ML , Ard Biesheuvel , Steven Rostedt , Peter Zijlstra , Thomas Gleixner , Linus Torvalds , Masami Hiramatsu , Jason Baron , Jiri Kosina , David Laight , Borislav Petkov Subject: Re: [PATCH RFC 0/3] Static calls Message-ID: <20181109152139.zig45f6gp24btfbc@treble> References: <20181109072811.GB86700@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20180716 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.42]); Fri, 09 Nov 2018 15:21:43 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 09, 2018 at 07:16:17AM -0800, Andy Lutomirski wrote: > On Thu, Nov 8, 2018 at 11:28 PM Ingo Molnar wrote: > > > > > > All other usecases are bonus, but it would certainly be interesting to > > investigate the impact of using these APIs for tracing: that too is a > > feature enabled everywhere but utilized only by a small fraction of Linux > > users - so literally every single cycle or instruction saved or hot-path > > shortened is a major win. > > For tracing, we'd want static_call_set_to_nop() or something like that, right? Are we talking about tracepoints? Or ftrace? -- Josh