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 Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8FF66C7EE25 for ; Wed, 7 Jun 2023 17:14:30 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4Qbv8j0lGvz3gCh for ; Thu, 8 Jun 2023 03:14:29 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=RH0aCUBx; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=139.178.84.217; helo=dfw.source.kernel.org; envelope-from=naveen@kernel.org; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=RH0aCUBx; dkim-atps=neutral Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4Qbv1610f4z3flY for ; Thu, 8 Jun 2023 03:07:54 +1000 (AEST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id F306360EB3; Wed, 7 Jun 2023 17:07:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E01E7C433D2; Wed, 7 Jun 2023 17:07:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1686157671; bh=MYdKVyeJNHIGE1EGa4r9r/X6+zpuy5PnbxLTM8nzVgM=; h=Date:From:Subject:To:Cc:References:In-Reply-To:From; b=RH0aCUBxP3yXDCR+0VyrWah7ZRCBlBr+zZD2lD373VUFIubsYd+56PkN8Iro0SGhp +Ii5R3S5dRISyHwqxKUW59p3IJDaScZpq9QHX12AB2V7JfKxiOp7DUkSClIrz6zj5A rB60/ayC46UZ/jxxQgaE2+lKC2KgbrGvnkzaMhRlmyG91xtviMCJ2dOqLISlQ4OLN8 yGbowSpEVbikAQmq6ucfL3BtYTmehgtl7v0Mi2r0R4DkfkhwjgoCbze5UKkNsuULdj OgBLDAXpbqGOi2Us+reF2B0KPtIMJhZ1UM4fRAf2xcaeefnNcuuFgbwHeDcm6aONsv TO2JNpmYPSLUQ== Date: Wed, 07 Jun 2023 22:35:21 +0530 From: Naveen N Rao Subject: Re: [RFC PATCH] powerpc/ftrace: Refactoring and support for -fpatchable-function-entry To: Christophe Leroy , "linuxppc-dev@lists.ozlabs.org" References: <20230519192600.2593506-1-naveen@kernel.org> <3527b8d2-275e-29d8-fd3b-4002a4a901fd@csgroup.eu> <85460820-e5e0-57e3-68a7-dd7a562c9eb0@csgroup.eu> <1684605928.yl2udzpst9.naveen@kernel.org> <5463949f-289b-1eae-17c7-f77f63389f98@csgroup.eu> <1684833778.7ege0impv3.naveen@kernel.org> <11217d67-a9bc-10a9-161c-c73666af0c9b@csgroup.eu> In-Reply-To: <11217d67-a9bc-10a9-161c-c73666af0c9b@csgroup.eu> MIME-Version: 1.0 User-Agent: astroid/0.16.0 (https://github.com/astroidmail/astroid) Message-Id: <1686157010.jpb26wrrqi.naveen@kernel.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Nicholas Piggin Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Christophe Leroy wrote: >=20 >=20 > Le 23/05/2023 =C3=A0 11:31, Naveen N Rao a =C3=A9crit=C2=A0: >> Christophe Leroy wrote: >>> >> Ok, I simplified this further, and this is as close to the previous=20 >> fast path as we can get (applies atop the original RFC). The only=20 >> difference left is the ftrace_rec iterator. >=20 > That's not better, that's even slightly worse (less than 1%). >=20 > I will try to investigate why. I have posted a follow-on RFC with the changes split up: http://lore.kernel.org/cover.1686151854.git.naveen@kernel.org Hopefully, that will help narrow down the source of the regression. - Naveen