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=-2.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 F1976C33C8C for ; Tue, 7 Jan 2020 17:47:54 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C34B22087F for ; Tue, 7 Jan 2020 17:47:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="osBDIRx9" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C34B22087F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender:Content-Type:Cc: List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: In-Reply-To:MIME-Version:References:Message-ID:Subject:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=0MqPu7orJ0ZJD3JWw6YlCGHjLND8WG1UjnhUsKMvZoo=; b=osBDIRx9vPYhiTtcnCrp/m8lW cK/qta2MbdrPvA/rmMfSg8dork9rICVsW9fVLGg3xwg2IRdUgN9/JjWIZMcYCeO/VV286Sk6wSPUW 83FXEIqiViBbjgmAwosMfqDtz8x+KLdM2tGAlzXAom22Qv7dmmbu4tUGhBUT/W6XhsC0lY0Ykzk9f oTDYnwYc7DLFSxtWY4tMpnQzYIaqIxnvuNWDs72cpnNFOJPsUx/zjXsIvoJUujo+Q6I6bj/ao9z2F AAObL0y2t6ZrU7cFXv0VMRs5uj7bh1udpv+QR+sFUlXt4ZBWYg/6RYFXrtReUR6/qH0zpZsGeI6uL HYeoog15Q==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iosxJ-0006OY-TA; Tue, 07 Jan 2020 17:47:49 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iosxH-0006Nv-5K for linux-arm-kernel@lists.infradead.org; Tue, 07 Jan 2020 17:47:48 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 1EF3A328; Tue, 7 Jan 2020 09:47:43 -0800 (PST) Received: from localhost (unknown [10.37.6.21]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9A4B63F534; Tue, 7 Jan 2020 09:47:42 -0800 (PST) Date: Tue, 7 Jan 2020 17:47:41 +0000 From: Mark Brown To: Will Deacon Subject: Re: [PATCH 2/3] arm64: lib: Use modern annotations for assembly functions Message-ID: <20200107174741.GG4877@sirena.org.uk> References: <20200106195818.56351-1-broonie@kernel.org> <20200106195818.56351-3-broonie@kernel.org> <20200107144445.GC29001@willie-the-truck> MIME-Version: 1.0 In-Reply-To: <20200107144445.GC29001@willie-the-truck> X-Cookie: Will Rogers never met you. User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200107_094747_242180_52537651 X-CRM114-Status: GOOD ( 20.44 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Catalin Marinas , linux-arm-kernel@lists.infradead.org, jslaby@suse.com Content-Type: multipart/mixed; boundary="===============0847093985647803636==" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org --===============0847093985647803636== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="Y+xroYBkGM9OatJL" Content-Disposition: inline --Y+xroYBkGM9OatJL Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Jan 07, 2020 at 02:44:46PM +0000, Will Deacon wrote: > On Mon, Jan 06, 2020 at 07:58:17PM +0000, Mark Brown wrote: > > -ENTRY(clear_page) > > +SYM_FUNC_START(clear_page) > > mrs x1, dczid_el0 > > and w1, w1, #0xf > > mov x2, #4 > Since this doesn't change behaviour, I think the patch is fine, however > on reading Documentation/asm-annotations.rst it's not completely clear to > me when SYM_FUNC_START() should be used. In this case, for example, we are > *not* pushing a stackframe and that would appear to be at odds with the > documentation. > Jiri -- is it ok to omit the stack frame for leaf functions annotated with > SYM_FUNC_START? I'm guessing it should be, since the link register isn't > going to be clobbered. Could we update the documentation to reflect that? Yeah, the documentation isn't great on that. I was going on the basis of both trying to minimize changes to the generated output as part of the bulk change and looking at it from the point of view of the caller - if as in this case the caller thinks it's a regular C function it seems sensible to annotate it as such. > > --- a/arch/arm64/lib/memcpy.S > > +++ b/arch/arm64/lib/memcpy.S > > @@ -57,11 +57,11 @@ > > .endm > > =20 > > .weak memcpy > Hmm, any idea why we use .weak explicitly here? Maybe better off using > the proper macros now? (same applies to many of the other lib/ functions > you're touching) Nope, there's a whole bunch of stuff where what we're currently doing is a bit interesting and I'm a bit worried that we might be relying on some of it. My theory here was to do the bulk of the changes as a 1:1 replacement so the generated output is as close as possible for any big changes and then do anything more detailed that isn't actually *needed* on top of that. It's looking like there'll also be some stuff that definitely changes the output going in as well, I was going to do those as individual patches so that it's easier to find any breakages that get introduced and so the big, repetitive changes don't have other stuff mixed in. --Y+xroYBkGM9OatJL Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAl4UxDwACgkQJNaLcl1U h9Awigf9HWFZ43nt9Kw7ijRMi+bx+iijYI/TNH08mOkeDlSvf2lilv9WPLop9VEX gtezchGJQNMHWntxM+6g0J60skBfkftjVgm+5sPni/WivURGQns9oYNqsmlWcJ4c Z/MvPIabeQ+mY/VlEZHbj0BmGWOOWnHUjPLkDM+c8uGz5u1flYL2G6MhY8DEqAG5 wOneKPlkoTI6kkfMyd8Xx0mPFpsQeM3OPvtauiZkVY239VSVUk6zkedlNWPljYJa O0CxWMnT97PQPnC47rBWJvURo5hc0K3lLw/UjrFTs8g3xhqnt70oYoAduHga3rhb 9BJwOhN0CCP15xa03EBpK+kZYD3qrw== =uZp6 -----END PGP SIGNATURE----- --Y+xroYBkGM9OatJL-- --===============0847093985647803636== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel --===============0847093985647803636==--