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=-0.6 required=3.0 tests=BAYES_40,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 8D07CC4363D for ; Wed, 23 Sep 2020 15:04:50 +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 B7E8D21D7D for ; Wed, 23 Sep 2020 15:04:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="MkYEExTq" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B7E8D21D7D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org 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 2FBFA13E1160E; Wed, 23 Sep 2020 08:04:49 -0700 (PDT) Received-SPF: None (mailfrom) identity=mailfrom; client-ip=2001:8b0:10b:1236::1; helo=casper.infradead.org; envelope-from=willy@infradead.org; receiver= Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id C81B613E1160C for ; Wed, 23 Sep 2020 08:04:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=Ose8ctZCTv8oUOd9k3tTT76nITLXgVZlsCte1r4Sf9c=; b=MkYEExTq1+wkaz83zMuspp5RjA Ql+JlgSLUtPgJQMk5ZRNIO+I2UvxTYWBAkIXlCxSLKN0kKXI86QBoGjW7A+yKUpkqMuuehrinsPuf iwX4oT+QNjApAyJGa8cH3EwMkixriTNBrfTFPhwDoOaCloAwyeLBZpcBeXr6ULKd7x6mz/VU1mrTF rjgPBXE/KVXkfXpLPhqrWyo99AM+ADFVOdaGRg6A3iJrv8o6ovKyridoI1mwkForkyoK8bF8rFGrw fd8w+PRxzla1bKvhyrYdLqm3AOmAqwCzB8te5Y2Zk6g0lBF64zMFMDuAmKdoz1JjyoTd9K7oNNJHv KnkoQvSQ==; Received: from willy by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1kL6Jn-0005Kf-EE; Wed, 23 Sep 2020 15:04:27 +0000 Date: Wed, 23 Sep 2020 16:04:27 +0100 From: Matthew Wilcox To: Mikulas Patocka Subject: Re: NVFS XFS metadata (was: [PATCH] pmem: export the symbols __copy_user_flushcache and __copy_from_user_flushcache) Message-ID: <20200923150427.GP32101@casper.infradead.org> References: <20200922050314.GB12096@dread.disaster.area> <20200923095739.GC6719@quack2.suse.cz> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Message-ID-Hash: ADGAV76VHTZWMI4ICG2IBCOVG3TVGKRL X-Message-ID-Hash: ADGAV76VHTZWMI4ICG2IBCOVG3TVGKRL X-MailFrom: willy@infradead.org X-Mailman-Rule-Hits: nonmember-moderation X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation CC: Jan Kara , Dave Chinner , Linus Torvalds , Alexander Viro , Andrew Morton , Eric Sandeen , Dave Chinner , "Tadakamadla, Rajesh (DCIG/CDI/HPS Perf)" , Linux Kernel Mailing List , linux-fsdevel , linux-nvdimm 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 On Wed, Sep 23, 2020 at 09:11:43AM -0400, Mikulas Patocka wrote: > I also don't know how to implement journling on persistent memory :) On > EXT4 or XFS you can pin dirty buffers in memory until the journal is > flushed. This is obviously impossible on persistent memory. So, I'm > considering implementing only some lightweight journaling that will > guarantee atomicity between just a few writes. That's a bit disappointing considering people have been publishing papers on how to do umpteen different variations on persistent memory journalling for the last five years. https://www.google.com/search?q=intel+persistent+memory+atomic+updates for example _______________________________________________ Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org To unsubscribe send an email to linux-nvdimm-leave@lists.01.org