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 3C568C6FA82 for ; Fri, 2 Sep 2022 20:53:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230442AbiIBUxy (ORCPT ); Fri, 2 Sep 2022 16:53:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46656 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229734AbiIBUxs (ORCPT ); Fri, 2 Sep 2022 16:53:48 -0400 Received: from mailout3.rbg.tum.de (mailout3.rbg.tum.de [131.159.0.8]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 086A9106DB4; Fri, 2 Sep 2022 13:53:32 -0700 (PDT) Received: from mailrelay1.rbg.tum.de (mailrelay1.in.tum.de [131.159.254.14]) by mailout3.rbg.tum.de (Postfix) with ESMTPS id 4E909100D1E; Fri, 2 Sep 2022 22:53:28 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=in.tum.de; s=20220209; t=1662152008; bh=U3TuavEmYauNSL5ReGEu5jSL5mPW0h3kY7JePUHK7IU=; h=Subject:From:In-Reply-To:Date:Cc:References:To:From; b=albk5apkHN/ADjaqURn83Kmx0Tp8rRhRiYbPfFMxDWOdwNGy98bjA4FEyUCNRxJ8b z802YlzGUDlEEOgX5JJ91qpi+TLYD2mZSDbRBj7hD7UU+nCm4+seoIUgfIytXvwHM7 gpn64G9gUpmSbECzCvdXFoVimABekQINC3Ftq5YcyVqOs779eAbK1QfsgMzV8wM8hE rLJQNIFK14oQV1CEjttQNXBNmb3bb5Q45ahwyRxMCahkzJBakHX31MqIiWGwXwDECf 68J8jSCq+e0H1ZXaib/YcL0FU0VaH/LGM4kCJj8UOArfe/N23MIY14RVDCT6oI/Cq1 QZV0lx2cxQBew== Received: by mailrelay1.rbg.tum.de (Postfix, from userid 112) id 4ABF81ABC; Fri, 2 Sep 2022 22:53:28 +0200 (CEST) Received: from mailrelay1.rbg.tum.de (localhost [127.0.0.1]) by mailrelay1.rbg.tum.de (Postfix) with ESMTP id 1CF701ABB; Fri, 2 Sep 2022 22:53:28 +0200 (CEST) Received: from mail.in.tum.de (vmrbg426.in.tum.de [131.159.0.73]) by mailrelay1.rbg.tum.de (Postfix) with ESMTPS id 18F1A1ABA; Fri, 2 Sep 2022 22:53:28 +0200 (CEST) Received: by mail.in.tum.de (Postfix, from userid 112) id 154884A0440; Fri, 2 Sep 2022 22:53:28 +0200 (CEST) Received: (Authenticated sender: heidekrp) by mail.in.tum.de (Postfix) with ESMTPSA id 51DDC4A007E; Fri, 2 Sep 2022 22:53:27 +0200 (CEST) (Extended-Queue-bit xtech_vk@fff.in.tum.de) Content-Type: multipart/signed; boundary="Apple-Mail=_DBB9647F-E8B8-49DF-9CDA-D6283A477504"; protocol="application/pkcs7-signature"; micalg=sha-256 Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3696.120.41.1.1\)) Subject: Re: [PATCH] tools/memory-model: Weaken ctrl dependency definition in explanation.txt From: =?utf-8?Q?Paul_Heidekr=C3=BCger?= In-Reply-To: Date: Fri, 2 Sep 2022 22:53:26 +0200 Cc: Joel Fernandes , Andrea Parri , Will Deacon , Peter Zijlstra , Boqun Feng , Nicholas Piggin , David Howells , Jade Alglave , Luc Maranget , "Paul E. McKenney" , Akira Yokosawa , Daniel Lustig , LKML , linux-arch , Marco Elver , Charalampos Mainas , Pramod Bhatotia , Soham Chakraborty , Martin Fink Content-Transfer-Encoding: quoted-printable Message-Id: <2FD673C3-F8FA-428C-B8B1-4DBC71AFDF0C@in.tum.de> References: <20220830204446.3590197-1-paul.heidekrueger@in.tum.de> <663d568d-a343-d44b-d33d-29998bff8f70@joelfernandes.org> <98f2b194-1fe6-3cd8-36cf-da017c35198f@joelfernandes.org> <935D3930-C369-4B0E-ACDC-5BFDFA85AA72@in.tum.de> To: Alan Stern X-Mailer: Apple Mail (2.3696.120.41.1.1) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --Apple-Mail=_DBB9647F-E8B8-49DF-9CDA-D6283A477504 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8 On 2. Sep 2022, at 16:18, Alan Stern wrote: > On Fri, Sep 02, 2022 at 10:40:34AM +0200, Paul Heidekr=C3=BCger wrote: >> On 31. Aug 2022, at 19:38, Alan Stern = wrote: >>>>> Finally, a read event X and another memory access event Y are = linked by a >>>>> control dependency if Y syntactically lies within an arm of an if >>>>> statement and X affects the evaluation of the if condition via a = data or >>>>> address dependency. Similarly for switch statements. >>>>=20 >>>> What do you think? >>>=20 >>> I like the second one. How about combining the last two sentences? =20= >>>=20 >>> ... via a data or address dependency (or similarly for a switch=20= >>> statement). >>=20 >> Yes, sounds good! >>=20 >>> Now I suppose someone will pipe up and ask about the conditional=20 >>> expressions in "for", "while" and "do" statements... :-) >>=20 >> Happy to have obliged :-) >> = https://lore.kernel.org/all/20F4C097-24B4-416B-95EE-AC11F5952B44@in.tum.de= / >>=20 >> Do you think the text should explicitly address control dependencies = in the >> context of loops as well? If yes, would it be a separate patch, or = would it >> make sense to combine it with this one? >=20 > Anything else should be a separate patch. >=20 > For the time being, I'm happy not to worry about loops. In the end > we'll probably have to describe them as though they were unrolled, > with all the complications that entails. OK, sounds good! Since there aren't any other immediate objections, I'll go ahead an = resubmit a v3 version of the patch with all the changes we discussed then. Many thanks, Paul= --Apple-Mail=_DBB9647F-E8B8-49DF-9CDA-D6283A477504 Content-Disposition: attachment; filename=smime.p7s Content-Type: application/pkcs7-signature; name=smime.p7s Content-Transfer-Encoding: base64 MIAGCSqGSIb3DQEHAqCAMIACAQExDzANBglghkgBZQMEAgEFADCABgkqhkiG9w0BBwEAAKCCEWow ggUSMIID+qADAgECAgkA4wvV+K8l2YEwDQYJKoZIhvcNAQELBQAwgYIxCzAJBgNVBAYTAkRFMSsw KQYDVQQKDCJULVN5c3RlbXMgRW50ZXJwcmlzZSBTZXJ2aWNlcyBHbWJIMR8wHQYDVQQLDBZULVN5 c3RlbXMgVHJ1c3QgQ2VudGVyMSUwIwYDVQQDDBxULVRlbGVTZWMgR2xvYmFsUm9vdCBDbGFzcyAy MB4XDTE2MDIyMjEzMzgyMloXDTMxMDIyMjIzNTk1OVowgZUxCzAJBgNVBAYTAkRFMUUwQwYDVQQK EzxWZXJlaW4genVyIEZvZXJkZXJ1bmcgZWluZXMgRGV1dHNjaGVuIEZvcnNjaHVuZ3NuZXR6ZXMg ZS4gVi4xEDAOBgNVBAsTB0RGTi1QS0kxLTArBgNVBAMTJERGTi1WZXJlaW4gQ2VydGlmaWNhdGlv biBBdXRob3JpdHkgMjCCASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBAMtg1/9moUHN0vqH l4pzq5lN6mc5WqFggEcVToyVsuXPztNXS43O+FZsFVV2B+pG/cgDRWM+cNSrVICxI5y+NyipCf8F XRgPxJiZN7Mg9mZ4F4fCnQ7MSjLnFp2uDo0peQcAIFTcFV9Kltd4tjTTwXS1nem/wHdN6r1ZB+Ba 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