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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 B4220C4CECF for ; Mon, 23 Sep 2019 20:23:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8840D205F4 for ; Mon, 23 Sep 2019 20:23:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2502571AbfIWUXy (ORCPT ); Mon, 23 Sep 2019 16:23:54 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:22352 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728856AbfIWUXx (ORCPT ); Mon, 23 Sep 2019 16:23:53 -0400 Received: from pps.filterd (m0098394.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x8NKLptd060389; Mon, 23 Sep 2019 16:23:21 -0400 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 2v72aqw6as-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 23 Sep 2019 16:23:20 -0400 Received: from m0098394.ppops.net (m0098394.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.27/8.16.0.27) with SMTP id x8NKM9tW063386; Mon, 23 Sep 2019 16:23:20 -0400 Received: from ppma03dal.us.ibm.com (b.bd.3ea9.ip4.static.sl-reverse.com [169.62.189.11]) by mx0a-001b2d01.pphosted.com with ESMTP id 2v72aqw6ab-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 23 Sep 2019 16:23:20 -0400 Received: from pps.filterd (ppma03dal.us.ibm.com [127.0.0.1]) by ppma03dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id x8NKJKTN027588; Mon, 23 Sep 2019 20:23:18 GMT Received: from b03cxnp08028.gho.boulder.ibm.com (b03cxnp08028.gho.boulder.ibm.com [9.17.130.20]) by ppma03dal.us.ibm.com with ESMTP id 2v5bg6v1em-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 23 Sep 2019 20:23:18 +0000 Received: from b03ledav005.gho.boulder.ibm.com (b03ledav005.gho.boulder.ibm.com [9.17.130.236]) by b03cxnp08028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x8NKNGNj62259636 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 23 Sep 2019 20:23:16 GMT Received: from b03ledav005.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id A8847BE051; Mon, 23 Sep 2019 20:23:16 +0000 (GMT) Received: from b03ledav005.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 3BE51BE04F; Mon, 23 Sep 2019 20:23:08 +0000 (GMT) Received: from leobras.br.ibm.com (unknown [9.18.235.184]) by b03ledav005.gho.boulder.ibm.com (Postfix) with ESMTP; Mon, 23 Sep 2019 20:23:08 +0000 (GMT) Message-ID: Subject: Re: [PATCH v2 11/11] powerpc/mm/book3s64/pgtable: Uses counting method to skip serializing From: Leonardo Bras To: John Hubbard , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Linux-MM Cc: Dan Williams , Arnd Bergmann , Jason Gunthorpe , Greg Kroah-Hartman , Mahesh Salgaonkar , YueHaibing , Nicholas Piggin , Mike Rapoport , Keith Busch , Richard Fontana , Paul Mackerras , "Aneesh Kumar K.V" , Ganesh Goudar , Thomas Gleixner , Ira Weiny , Andrew Morton , Allison Randal Date: Mon, 23 Sep 2019 17:23:03 -0300 In-Reply-To: <1568b3ef-cec9-bf47-edaa-c775c2f544fb@nvidia.com> References: <20190920195047.7703-1-leonardo@linux.ibm.com> <20190920195047.7703-12-leonardo@linux.ibm.com> <1b39eaa7-751d-40bc-d3d7-41aaa15be42a@nvidia.com> <24863d8904c6e05e5dd48cab57db4274675ae654.camel@linux.ibm.com> <4ea26ffb-ad03-bdff-7893-95332b22a5fd@nvidia.com> <18c5c378db98f223a0663034baa9fd6ce42f1ec7.camel@linux.ibm.com> <8706a1f1-0c5e-d152-938b-f355b9a5aaa8@nvidia.com> <1568b3ef-cec9-bf47-edaa-c775c2f544fb@nvidia.com> Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-rL8yHUayTEy37kqretQV" User-Agent: Evolution 3.30.5 (3.30.5-1.fc29) MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-09-23_07:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1909230170 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-rL8yHUayTEy37kqretQV Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Mon, 2019-09-23 at 12:58 -0700, John Hubbard wrote: >=20 > CPU 0 CPU 1 > ------ -------------- > READ(pte) (re-ordered at run time) > atomic_inc(val) (no run-time memory barrie= r!) > =20 > pmd_clear(pte) > if (val) > run_on_all_cpus(): IPI > local_irq_disable() (also not a mem barrie= r) >=20 > if(pte) > walk page tables Let me see if I can understand, On most patches, it would be: CPU 0 CPU 1 ------ -------------- ptep =3D __find_linux_pte =20 (re-ordered at run time) atomic_inc(val)=20 pmd_clear(pte) smp_mb() if (val) run_on_all_cpus(): IPI local_irq_disable()=20 if(ptep) pte =3D *ptep; Is that what you meant? --=-rL8yHUayTEy37kqretQV Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEMdeUgIzgjf6YmUyOlQYWtz9SttQFAl2JKacACgkQlQYWtz9S ttQNQQ//YZoIqwIEI8Lrj+C7R1TaXBuOjUoK9YNDTE6IjHRf1s5nkhUpn68/joo+ VKKvccIS6lJFZOMq9cpBn8/UtitXlmTwmM3zmfSRzKjXQJZJk2IeioBlB5d16L9q Y8IS8kojfI3DoDDF5XRGU+FQbwMUqTNkKpvWevAotkldLhE2ZvUkoJSEUM7X4MqQ C67Pbbgpsz+q5ZcEW6JbAolW6/nQXYCevzRj8hJ1+inreFKp7KoiBsOebVvW4LMD L6GhEJiKvgFK2HpqEECNApqDDFnPDh0CxELo/sf4J0eV5hVKSkZrpJaJBVUmCQ+9 Z6rn7BHQd/uM0P9bqWvv6+M+IVriOuwNZ/jRe312heD7IlWDccytoqRjo5xfuBUp PTowmJ/zUUH7bpPEAnVP3qzEqyvMsUKiVuYK9Fxnfx+fMLVokjbXvosRoLJ8+I8d 71xd5iyjyIGRoxntKukRNpwrPoftF7dTVFHTpYwstM7FQXrGEex5wnnLwXGeOwUF gevW1ayr2mu0u/TchxKO0tvCeu8gVnbiBmtEsJYIXMTAt8RGNqKBcekYnuFUAIuq hF7Qg2DGeGlwjMwdpWZBNSBv8Fvq45Y/m0ggvH3Ey18WF3rwS9FDWbT/ix4PEJUC x2GH0X9bTNwrhVLjwRPuHyOVMfulhA1DVbRq+H+/2cNXr6ewLNE= =DGT/ -----END PGP SIGNATURE----- --=-rL8yHUayTEy37kqretQV-- 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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 81654C4CECF for ; Mon, 23 Sep 2019 20:25:54 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 A2F73205F4 for ; Mon, 23 Sep 2019 20:25:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A2F73205F4 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 46cbRz24SQzDqLh for ; Tue, 24 Sep 2019 06:25:51 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=linux.ibm.com (client-ip=148.163.156.1; helo=mx0a-001b2d01.pphosted.com; envelope-from=leonardo@linux.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 46cbPR2PP8zDqJL for ; Tue, 24 Sep 2019 06:23:37 +1000 (AEST) Received: from pps.filterd (m0098394.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x8NKLptd060389; Mon, 23 Sep 2019 16:23:21 -0400 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 2v72aqw6as-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 23 Sep 2019 16:23:20 -0400 Received: from m0098394.ppops.net (m0098394.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.27/8.16.0.27) with SMTP id x8NKM9tW063386; Mon, 23 Sep 2019 16:23:20 -0400 Received: from ppma03dal.us.ibm.com (b.bd.3ea9.ip4.static.sl-reverse.com [169.62.189.11]) by mx0a-001b2d01.pphosted.com with ESMTP id 2v72aqw6ab-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 23 Sep 2019 16:23:20 -0400 Received: from pps.filterd (ppma03dal.us.ibm.com [127.0.0.1]) by ppma03dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id x8NKJKTN027588; Mon, 23 Sep 2019 20:23:18 GMT Received: from b03cxnp08028.gho.boulder.ibm.com (b03cxnp08028.gho.boulder.ibm.com [9.17.130.20]) by ppma03dal.us.ibm.com with ESMTP id 2v5bg6v1em-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 23 Sep 2019 20:23:18 +0000 Received: from b03ledav005.gho.boulder.ibm.com (b03ledav005.gho.boulder.ibm.com [9.17.130.236]) by b03cxnp08028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x8NKNGNj62259636 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 23 Sep 2019 20:23:16 GMT Received: from b03ledav005.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id A8847BE051; Mon, 23 Sep 2019 20:23:16 +0000 (GMT) Received: from b03ledav005.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 3BE51BE04F; Mon, 23 Sep 2019 20:23:08 +0000 (GMT) Received: from leobras.br.ibm.com (unknown [9.18.235.184]) by b03ledav005.gho.boulder.ibm.com (Postfix) with ESMTP; Mon, 23 Sep 2019 20:23:08 +0000 (GMT) Message-ID: Subject: Re: [PATCH v2 11/11] powerpc/mm/book3s64/pgtable: Uses counting method to skip serializing From: Leonardo Bras To: John Hubbard , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Linux-MM Date: Mon, 23 Sep 2019 17:23:03 -0300 In-Reply-To: <1568b3ef-cec9-bf47-edaa-c775c2f544fb@nvidia.com> References: <20190920195047.7703-1-leonardo@linux.ibm.com> <20190920195047.7703-12-leonardo@linux.ibm.com> <1b39eaa7-751d-40bc-d3d7-41aaa15be42a@nvidia.com> <24863d8904c6e05e5dd48cab57db4274675ae654.camel@linux.ibm.com> <4ea26ffb-ad03-bdff-7893-95332b22a5fd@nvidia.com> <18c5c378db98f223a0663034baa9fd6ce42f1ec7.camel@linux.ibm.com> <8706a1f1-0c5e-d152-938b-f355b9a5aaa8@nvidia.com> <1568b3ef-cec9-bf47-edaa-c775c2f544fb@nvidia.com> Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-rL8yHUayTEy37kqretQV" User-Agent: Evolution 3.30.5 (3.30.5-1.fc29) MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-09-23_07:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1909230170 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: Andrew Morton , Arnd Bergmann , Richard Fontana , Mahesh Salgaonkar , YueHaibing , Nicholas Piggin , Mike Rapoport , Keith Busch , Jason Gunthorpe , Paul Mackerras , "Aneesh Kumar K.V" , Greg Kroah-Hartman , Ganesh Goudar , Dan Williams , Ira Weiny , Thomas Gleixner , Allison Randal Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" --=-rL8yHUayTEy37kqretQV Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Mon, 2019-09-23 at 12:58 -0700, John Hubbard wrote: >=20 > CPU 0 CPU 1 > ------ -------------- > READ(pte) (re-ordered at run time) > atomic_inc(val) (no run-time memory barrie= r!) > =20 > pmd_clear(pte) > if (val) > run_on_all_cpus(): IPI > local_irq_disable() (also not a mem barrie= r) >=20 > if(pte) > walk page tables Let me see if I can understand, On most patches, it would be: CPU 0 CPU 1 ------ -------------- ptep =3D __find_linux_pte =20 (re-ordered at run time) atomic_inc(val)=20 pmd_clear(pte) smp_mb() if (val) run_on_all_cpus(): IPI local_irq_disable()=20 if(ptep) pte =3D *ptep; Is that what you meant? --=-rL8yHUayTEy37kqretQV Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEMdeUgIzgjf6YmUyOlQYWtz9SttQFAl2JKacACgkQlQYWtz9S ttQNQQ//YZoIqwIEI8Lrj+C7R1TaXBuOjUoK9YNDTE6IjHRf1s5nkhUpn68/joo+ VKKvccIS6lJFZOMq9cpBn8/UtitXlmTwmM3zmfSRzKjXQJZJk2IeioBlB5d16L9q Y8IS8kojfI3DoDDF5XRGU+FQbwMUqTNkKpvWevAotkldLhE2ZvUkoJSEUM7X4MqQ C67Pbbgpsz+q5ZcEW6JbAolW6/nQXYCevzRj8hJ1+inreFKp7KoiBsOebVvW4LMD L6GhEJiKvgFK2HpqEECNApqDDFnPDh0CxELo/sf4J0eV5hVKSkZrpJaJBVUmCQ+9 Z6rn7BHQd/uM0P9bqWvv6+M+IVriOuwNZ/jRe312heD7IlWDccytoqRjo5xfuBUp PTowmJ/zUUH7bpPEAnVP3qzEqyvMsUKiVuYK9Fxnfx+fMLVokjbXvosRoLJ8+I8d 71xd5iyjyIGRoxntKukRNpwrPoftF7dTVFHTpYwstM7FQXrGEex5wnnLwXGeOwUF gevW1ayr2mu0u/TchxKO0tvCeu8gVnbiBmtEsJYIXMTAt8RGNqKBcekYnuFUAIuq hF7Qg2DGeGlwjMwdpWZBNSBv8Fvq45Y/m0ggvH3Ey18WF3rwS9FDWbT/ix4PEJUC x2GH0X9bTNwrhVLjwRPuHyOVMfulhA1DVbRq+H+/2cNXr6ewLNE= =DGT/ -----END PGP SIGNATURE----- --=-rL8yHUayTEy37kqretQV--