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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7206CC433EF for ; Tue, 22 Feb 2022 13:42:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231889AbiBVNnC (ORCPT ); Tue, 22 Feb 2022 08:43:02 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43746 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231741AbiBVNnB (ORCPT ); Tue, 22 Feb 2022 08:43:01 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 82738119843 for ; Tue, 22 Feb 2022 05:42:36 -0800 (PST) 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 sin.source.kernel.org (Postfix) with ESMTPS id B5BB0CE1285 for ; Tue, 22 Feb 2022 13:42:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 10505C340E8; Tue, 22 Feb 2022 13:42:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1645537353; bh=Dgt4Njyb87/1m9sSS9cByUyH93W7hgmQZXT2bQcvLbM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=FS2HTkxtW64sxuVW8n0wSjhFlnRTJuMQnIZ8Xql1lrAR2ox/DacMZ9PAdsJk6UWK/ mu+lY9POXbUOs0c2AHa+OGNgqOtv+kg9mpdjVN3o56QsCE8yey3T6RwZOLC+uJnAYn E5l5gg+GY4HB9yJg74dQ1KkkL00YZaQid3Lj1x7SSfNKlW5Oq30olisneiH6HghyJl tgkN+zOyCjmG8tw7x6KTV7YQSGw6NLul3xsoE+xyTYTzQnpAE0Sl59MMFaYKX1VDT0 K3MLAy35yo2hAhq3M0LaJkWHiJ9nfqMM7pGsbSBMCeiQphDm/8HWb0tstH8e8u5vTp 5JdcGAvVtr6ag== Date: Tue, 22 Feb 2022 13:42:26 +0000 From: Mark Brown To: Catalin Marinas Cc: Will Deacon , Marc Zyngier , Shuah Khan , Shuah Khan , Alan Hayward , Luis Machado , Salil Akerkar , Basant Kumar Dwivedi , Szabolcs Nagy , James Morse , Alexandru Elisei , Suzuki K Poulose , linux-arm-kernel@lists.infradead.org, linux-kselftest@vger.kernel.org, kvmarm@lists.cs.columbia.edu Subject: Re: [PATCH v11 16/40] arm64/sme: Implement streaming SVE context switching Message-ID: References: <20220207152109.197566-1-broonie@kernel.org> <20220207152109.197566-17-broonie@kernel.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="HCJoz7wijUUjw35T" Content-Disposition: inline In-Reply-To: X-Cookie: I smell a wumpus. Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org --HCJoz7wijUUjw35T Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Feb 22, 2022 at 12:53:11PM +0000, Catalin Marinas wrote: > I think I get this but a state diagram somewhere would help ;). > IIUC you don't disable SM on a context switch, you just leave it in > place until a task_fpsimd_load(). It shouldn't be a problem as > kernel_neon_begin() disables it anyway. Yes, streaming mode is part of the floating point state and this is how we handle floating point in general - it's part of what's tracked with TIF_FOREIGN_FPSTATE. Unless we want to do something with floating point we don't touch it. --HCJoz7wijUUjw35T Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmIU6EIACgkQJNaLcl1U h9AQKwf+NQfS1WFJTmF/zyR2Ew84K70XTrrLzPlgOF24CCCSuihIA3ZF22mUWYB4 W3snzj3yvOJioOrceWBR/rcSXdLqQy/KDO9CUbWAkShtfo4uukYgS9pivUZAEm8m f+tJg3ktwvR7iO/wrYW65kfYAlwxSdzjXbUBFb8BkcwVjiezVOWVR1cZp8WV47DC pIztOPzukFtV1lwiwZw6/p9M0qhsrXooLGBXcDw99t5WWWyfSF0sXREO8V1C0Tx5 zWULO6hCfSr9uK9T19lMG/FXDSnrV+3A0QuWZY2qMJiub1mgKJH/ofRKCNHnnJSR 70fYhIlRd5nXUGingt6IIJaIp/tQbw== =JTyO -----END PGP SIGNATURE----- --HCJoz7wijUUjw35T--