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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 autolearn=no 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 48F78C388F7 for ; Wed, 28 Oct 2020 23:16:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E9D70206FB for ; Wed, 28 Oct 2020 23:16:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387943AbgJ1XQW (ORCPT ); Wed, 28 Oct 2020 19:16:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:46312 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727999AbgJ1XQV (ORCPT ); Wed, 28 Oct 2020 19:16:21 -0400 Received: from oasis.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1D1AC206FB; Wed, 28 Oct 2020 23:16:18 +0000 (UTC) Date: Wed, 28 Oct 2020 19:16:16 -0400 From: Steven Rostedt To: Alexei Starovoitov Cc: linux-kernel@vger.kernel.org, Masami Hiramatsu , Andrew Morton , Jiri Olsa , Thomas Gleixner , Peter Zijlstra , Ingo Molnar Subject: Re: [RFC][PATCH 0/2] ftrace: Add access to function arguments for all callbacks Message-ID: <20201028191616.0268d32a@oasis.local.home> In-Reply-To: <20201028230305.zhtpwektsehh54bv@ast-mbp.dhcp.thefacebook.com> References: <20201028131542.963014814@goodmis.org> <20201028213303.shosfclmhxkai2ir@ast-mbp.dhcp.thefacebook.com> <20201028180753.238335d1@oasis.local.home> <20201028230305.zhtpwektsehh54bv@ast-mbp.dhcp.thefacebook.com> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 28 Oct 2020 16:03:05 -0700 Alexei Starovoitov wrote: > I don't understand what you're trying to say. > Are we still discussing your patch or something else? > If your patch then, I said, I'm not against it. I just don't see > a value in it. Since you're agree that regs_get_kernel_argument() > is misleading then what's the point of the patch? I agree that it can be meaningless, but it can also be useful for debugging purposes. It works just fine on x86_32 (even when you access 4 or more arguments). One just needs to understand the arch (as a long long will be broken up across "two" arguments). But even that is really useful for finding out what's going on. > To make mini-SAVE_REGS version? For what kind of use case? If the types of the arguments are known, and you have a mini-SAVE_REGS, can't you still get the true arguments? -- Steve