From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7B60B357D02 for ; Mon, 1 Jun 2026 19:25:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780341907; cv=none; b=bx8NRlClhX1ZlZ7nDxbd17Ym0jOFB/hY8Kh4WEB7A0tjDHiA/C1sjykv9pGao+sO46H1YiG8NabxP/r9l1rELS6MSqsUfcGpEfo5EFDQN2Hf70icVBOBjy3TMWZ68GKzRK1qUC2FucJotuQ/O/h/HK8KqI1NOXZIh45lZUyABO4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780341907; c=relaxed/simple; bh=BNqin2jfxILERW9NSk/mbobX5ciQJDLQjzAjR2Tb+yU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=jqMIQiMm97bhuJbkpK298UkooLyQJUQHAdlkHAZFQZzMZjLqB85LLLK/D4ivouWlqNwQpivdfgyM/OKuwVFSyqKE5816F7m9JQuQP8E/UP9/A9fet3flK0KOXb/MgzK1w0tr2KGPLyPDvlmHxmU6KjbcVtlYGlYTV/LKU7jNoA0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=GD4K50df; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="GD4K50df" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9C2D61F00893; Mon, 1 Jun 2026 19:25:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780341906; bh=230brXIz/1I/P6fKDlh4upgsCSxJ34MkrrrfA/T/Ijo=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=GD4K50dfce5PduU9oUcGN46Z4x+5nHZyMPg8XIF+ZB3xXwKJtyOBNj5dejiu6Cwu7 F8RFUFkR4749uWNAKwGpGDyqNm/101I2ma9CzmuD89jzBSR/eTfzFNU1WKdArZa+1y LQ71C8bIFHVwGPIcnn9MFGmXFw1d7zqO3b0sxgnVGUi1wrYjTWtWFEOCwitGc1+EBD RVnnMjdHTYXwfh/VUdMgR0aseO6GRI3ov/N+6CnaI4Up+G44Nta7G2nfqd4gUHy9mP VrVXuFr6sJ0d370dioWEcbSMnKiz2xK7jek8IdH58wrewz/rDOaCxacbNVZ5Nd7PxI 6rI4dtxgblBcA== Date: Mon, 1 Jun 2026 12:24:58 -0700 From: Nathan Chancellor To: Rong Xu Cc: Yabin Cui , Will Deacon , Han Shen , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Kees Cook , Nicolas Schier , Linus Walleij , Arnd Bergmann , Mathieu Desnoyers , Miguel Ojeda , Peter Zijlstra , Jinjie Ruan , Lukas Bulwahn , linux-kernel@vger.kernel.org, Juergen Gross , Helge Deller , Ryan Roberts , Marc Zyngier , Ard Biesheuvel , Vincent Donnefort , Alice Ryhl , x86@kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v3 1/2] kconfig: Remove the architecture specific config for AutoFDO Message-ID: <20260601192458.GB965997@ax162> References: <20260527214510.3907973-1-xur@google.com> <20260527214510.3907973-2-xur@google.com> <178010203121.3743687.8945076194906841190.b4-review@b4> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Mon, Jun 01, 2026 at 09:52:56AM -0700, Rong Xu wrote: > On Fri, May 29, 2026 at 5:47 PM Nathan Chancellor wrote: > > > > On Wed, 27 May 2026 14:45:07 -0700, xur@google.com wrote: > > > The CONFIG_AUTOFDO_CLANG option currently depends on > > > ARCH_SUPPORTS_AUTOFDO_CLANG, but this dependency seems unnecessary. > > > > > > Remove ARCH_SUPPORTS_AUTOFDO_CLANG and allow users to control AutoFDO > > > builds solely through CONFIG_AUTOFDO_CLANG. This simplifies the kconfig > > > and avoids potential confusion. > > > > It is worth noting that not all architectures support > > '-fsplit-machine-functions' but I guess that does not matter too much > > because it will only be used if a profile is provided, which would > > require an architecture that is supported by the AutoFDO tooling? The > > documentation is x86_64 focused but aarch64 works as well, any others > > that the kernel supports? > > Current support extends to x86_64 and arm64 architectures only. > > We initially considered making arm64 to opt-in, Will suggests that users should > be expected to verify AutoFDO/Propeller compatibility independently > before using it. > This approach allows for the removal of ARCH_SUPPORTS_..., which prevents > potential confusion. Right, in cases where the build does not break (i.e., this case), I think it is fine to leave things open to selection and restrict them when they become confusing or problematic for users based on real feedback. -- Cheers, Nathan