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=-6.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham 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 7E703C32771 for ; Wed, 15 Jan 2020 16:55:40 +0000 (UTC) Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (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 485EE214AF for ; Wed, 15 Jan 2020 16:55:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="LqlB/C5C" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 485EE214AF Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvdimm-bounces@lists.01.org Received: from ml01.vlan13.01.org (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id 895DC10097DC7; Wed, 15 Jan 2020 08:58:58 -0800 (PST) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=205.139.110.120; helo=us-smtp-1.mimecast.com; envelope-from=jmoyer@redhat.com; receiver= Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [205.139.110.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 1EBDE10097DC5 for ; Wed, 15 Jan 2020 08:58:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1579107337; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=aiHy9sVh9o7u8SSTG9b+BoOWpHEYOVZOoS63pLilv8A=; b=LqlB/C5C2/ZewzLO/nG2GNndrKbUGxcIcDB69f2Mu4XhaULjWOFZXI7Vn2S9nvdZZD+E06 mIWHn9n5n15MBTYEms7dWO5qPpBpCpI/DZwP4rIOAML7yEF+avmibcZKDVDQuw5kT0aK3J JW1uXMP/MF0SbgHGW1NIlYpffar4RNs= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-270-Vmp3RQsmNtCNXXfRZsBGsw-1; Wed, 15 Jan 2020 11:55:33 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 70C258E0F62; Wed, 15 Jan 2020 16:55:32 +0000 (UTC) Received: from segfault.boston.devel.redhat.com (segfault.boston.devel.redhat.com [10.19.60.26]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0701A811E0; Wed, 15 Jan 2020 16:55:31 +0000 (UTC) From: Jeff Moyer To: "Aneesh Kumar K.V" Subject: Re: [RFC PATCH] libnvdimm: Update the meaning for persistence_domain values References: <20200108064905.170394-1-aneesh.kumar@linux.ibm.com> X-PGP-KeyID: 1F78E1B4 X-PGP-CertKey: F6FE 280D 8293 F72C 65FD 5A58 1FF8 A7CA 1F78 E1B4 Date: Wed, 15 Jan 2020 11:55:30 -0500 In-Reply-To: <20200108064905.170394-1-aneesh.kumar@linux.ibm.com> (Aneesh Kumar K. V.'s message of "Wed, 8 Jan 2020 12:19:05 +0530") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-MC-Unique: Vmp3RQsmNtCNXXfRZsBGsw-1 X-Mimecast-Spam-Score: 0 Message-ID-Hash: DCUWKY2AWYJO5YRRD7RVL7NVRVTOV53E X-Message-ID-Hash: DCUWKY2AWYJO5YRRD7RVL7NVRVTOV53E X-MailFrom: jmoyer@redhat.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; suspicious-header CC: linux-nvdimm@lists.01.org X-Mailman-Version: 3.1.1 Precedence: list List-Id: "Linux-nvdimm developer list." Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit "Aneesh Kumar K.V" writes: > Currently, kernel shows the below values > "persistence_domain":"cpu_cache" > "persistence_domain":"memory_controller" > "persistence_domain":"unknown" > > This patch updates the meaning of these values such that > > "cpu_cache" indicates no extra instructions is needed to ensure the persistence > of data in the pmem media on power failure. > > "memory_controller" indicates platform provided instructions need to be issued > as per documented sequence to make sure data flushed is guaranteed to be on pmem > media in case of system power loss. > > Signed-off-by: Aneesh Kumar K.V > --- > arch/powerpc/platforms/pseries/papr_scm.c | 7 ++++++- > include/linux/libnvdimm.h | 6 +++--- > 2 files changed, 9 insertions(+), 4 deletions(-) > > diff --git a/arch/powerpc/platforms/pseries/papr_scm.c b/arch/powerpc/platforms/pseries/papr_scm.c > index c2ef320ba1bf..26a5ef263758 100644 > --- a/arch/powerpc/platforms/pseries/papr_scm.c > +++ b/arch/powerpc/platforms/pseries/papr_scm.c > @@ -360,8 +360,13 @@ static int papr_scm_nvdimm_init(struct papr_scm_priv *p) > > if (p->is_volatile) > p->region = nvdimm_volatile_region_create(p->bus, &ndr_desc); > - else > + else { > + /* > + * We need to flush things correctly to guarantee persistance > + */ > + set_bit(ND_REGION_PERSIST_MEMCTRL, &ndr_desc.flags); > p->region = nvdimm_pmem_region_create(p->bus, &ndr_desc); > + } > if (!p->region) { > dev_err(dev, "Error registering region %pR from %pOF\n", > ndr_desc.res, p->dn); Would you also update of_pmem to indicate the persistence domain, please? > diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h > index f2a33f2e3ba8..9126737377e1 100644 > --- a/include/linux/libnvdimm.h > +++ b/include/linux/libnvdimm.h > @@ -52,9 +52,9 @@ enum { > */ > ND_REGION_PERSIST_CACHE = 1, > /* > - * Platform provides mechanisms to automatically flush outstanding > - * write data from memory controler to pmem on system power loss. > - * (ADR) > + * Platform provides instructions to flush data such that on completion > + * of the instructions, data flushed is guaranteed to be on pmem even > + * in case of a system power loss. I find the prior description easier to understand. -Jeff _______________________________________________ Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org To unsubscribe send an email to linux-nvdimm-leave@lists.01.org