From patchwork Mon Jun 1 19:36:33 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Toshi Kani X-Patchwork-Id: 6524491 Return-Path: X-Original-To: patchwork-linux-nvdimm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id D39ECC0020 for ; Mon, 1 Jun 2015 19:56:37 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id ECB68204A9 for ; Mon, 1 Jun 2015 19:56:36 +0000 (UTC) Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 027DF204FF for ; Mon, 1 Jun 2015 19:56:36 +0000 (UTC) Received: from ml01.vlan14.01.org (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id EA5871827EC; Mon, 1 Jun 2015 12:56:35 -0700 (PDT) X-Original-To: linux-nvdimm@lists.01.org Delivered-To: linux-nvdimm@lists.01.org Received: from g9t5009.houston.hp.com (g9t5009.houston.hp.com [15.240.92.67]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 1A23B1827EB for ; Mon, 1 Jun 2015 12:56:35 -0700 (PDT) Received: from g4t3433.houston.hp.com (g4t3433.houston.hp.com [16.210.25.219]) by g9t5009.houston.hp.com (Postfix) with ESMTP id 67D67BC; Mon, 1 Jun 2015 19:56:34 +0000 (UTC) Received: from misato.fc.hp.com (misato.fc.hp.com [16.78.168.61]) by g4t3433.houston.hp.com (Postfix) with ESMTP id 0A93E5F; Mon, 1 Jun 2015 19:56:32 +0000 (UTC) From: Toshi Kani To: bp@alien8.de, hpa@zytor.com, tglx@linutronix.de, mingo@redhat.com, akpm@linux-foundation.org, arnd@arndb.de Subject: [PATCH v12 10/10] drivers/block/pmem: Map NVDIMM with ioremap_wt() Date: Mon, 1 Jun 2015 13:36:33 -0600 Message-Id: <1433187393-22688-11-git-send-email-toshi.kani@hp.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1433187393-22688-1-git-send-email-toshi.kani@hp.com> References: <1433187393-22688-1-git-send-email-toshi.kani@hp.com> Cc: jgross@suse.com, konrad.wilk@oracle.com, linux-nvdimm@lists.01.org, mcgrof@suse.com, x86@kernel.org, linux-kernel@vger.kernel.org, stefan.bader@canonical.com, luto@amacapital.net, linux-mm@kvack.org, hmh@hmh.eng.br, hch@lst.de X-BeenThere: linux-nvdimm@lists.01.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: "Linux-nvdimm developer list." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The pmem driver maps NVDIMM with ioremap_nocache() as we cannot write back the contents of the CPU caches in case of a crash. This patch changes to use ioremap_wt(), which provides uncached writes but cached reads, for improving read performance. Signed-off-by: Toshi Kani Acked-by: Dan Williams --- drivers/block/pmem.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/block/pmem.c b/drivers/block/pmem.c index eabf4a8..095dfaa 100644 --- a/drivers/block/pmem.c +++ b/drivers/block/pmem.c @@ -139,11 +139,11 @@ static struct pmem_device *pmem_alloc(struct device *dev, struct resource *res) } /* - * Map the memory as non-cachable, as we can't write back the contents + * Map the memory as write-through, as we can't write back the contents * of the CPU caches in case of a crash. */ err = -ENOMEM; - pmem->virt_addr = ioremap_nocache(pmem->phys_addr, pmem->size); + pmem->virt_addr = ioremap_wt(pmem->phys_addr, pmem->size); if (!pmem->virt_addr) goto out_release_region;