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 0C203C4829E for ; Mon, 12 Feb 2024 18:24:50 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4TYXtS4vx0z3cCb for ; Tue, 13 Feb 2024 05:24:48 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.crashing.org (client-ip=63.228.1.57; helo=gate.crashing.org; envelope-from=segher@kernel.crashing.org; receiver=lists.ozlabs.org) Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) by lists.ozlabs.org (Postfix) with ESMTP id 4TYXt06t5rz3cB0 for ; Tue, 13 Feb 2024 05:24:24 +1100 (AEDT) Received: from gate.crashing.org (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id 41CINMII015661; Mon, 12 Feb 2024 12:23:22 -0600 Received: (from segher@localhost) by gate.crashing.org (8.14.1/8.14.1/Submit) id 41CINM2n015660; Mon, 12 Feb 2024 12:23:22 -0600 X-Authentication-Warning: gate.crashing.org: segher set sender to segher@kernel.crashing.org using -f Date: Mon, 12 Feb 2024 12:23:22 -0600 From: Segher Boessenkool To: Timothy Pearson Subject: Re: [PATCH] powerpc: Add gpr1 and fpu save/restore functions Message-ID: <20240212182322.GZ19790@gate.crashing.org> References: <995988479.14839534.1707756078600.JavaMail.zimbra@raptorengineeringinc.com> <20240212170207.GW19790@gate.crashing.org> <1251499652.14843228.1707757778984.JavaMail.zimbra@raptorengineeringinc.com> <20240212173043.GX19790@gate.crashing.org> <572013249.14851324.1707759979044.JavaMail.zimbra@raptorengineeringinc.com> <20240212175906.GY19790@gate.crashing.org> <1119220086.14855806.1707761223318.JavaMail.zimbra@raptorengineeringinc.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1119220086.14855806.1707761223318.JavaMail.zimbra@raptorengineeringinc.com> User-Agent: Mutt/1.4.2.3i 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: linuxppc-dev Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Mon, Feb 12, 2024 at 12:07:03PM -0600, Timothy Pearson wrote: > > I have done it for *all* architectures some ten years ago. Never found > > any problem. > > That makes sense, what I mean by invasive is that we'd need buy-in from the other > maintainers across all of the affected architectures. Is that likely to occur? I don't know. Here is my PowerPC-specific patch, it's a bit older, it might not apply cleanly anymore, the changes needed should be obvious though: === 8< === commit f16dfa5257eb14549ce22243fb2b465615085134 Author: Segher Boessenkool Date: Sat May 3 03:48:06 2008 +0200 powerpc: Link vmlinux against libgcc.a diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile index b7212b619c52..0a2fac6ffc1c 100644 --- a/arch/powerpc/Makefile +++ b/arch/powerpc/Makefile @@ -158,6 +158,9 @@ core-y += arch/powerpc/kernel/ core-$(CONFIG_XMON) += arch/powerpc/xmon/ core-$(CONFIG_KVM) += arch/powerpc/kvm/ +LIBGCC := $(shell $(CC) $(KBUILD_CFLAGS) -print-libgcc-file-name) +libs-y += $(LIBGCC) + drivers-$(CONFIG_OPROFILE) += arch/powerpc/oprofile/ # Default to zImage, override when needed === 8< === > > There are better options than -Os, fwiw. Some --param's give smaller > > *and* faster kernels. What exactly is best is heavily arch-dependent > > though (as well as dependent on the application code, the kernel code in > > this case) :-( > > I've been through this a few times, and -Os is the only option that makes > things (just barely) fit unfortunately. -O2 with appropriate inlining tuning beats -Os every day of the week, in my experience. Segher