From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ob0-f172.google.com (mail-ob0-f172.google.com [209.85.214.172]) by kanga.kvack.org (Postfix) with ESMTP id 81EFC6B007B for ; Mon, 1 Jun 2015 15:56:35 -0400 (EDT) Received: by obew15 with SMTP id w15so112317791obe.1 for ; Mon, 01 Jun 2015 12:56:35 -0700 (PDT) Received: from g9t5009.houston.hp.com (g9t5009.houston.hp.com. [15.240.92.67]) by mx.google.com with ESMTPS id fy16si9391516oeb.33.2015.06.01.12.56.34 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 01 Jun 2015 12:56:34 -0700 (PDT) From: Toshi Kani 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> In-Reply-To: <1433187393-22688-1-git-send-email-toshi.kani@hp.com> References: <1433187393-22688-1-git-send-email-toshi.kani@hp.com> Sender: owner-linux-mm@kvack.org List-ID: To: bp@alien8.de, hpa@zytor.com, tglx@linutronix.de, mingo@redhat.com, akpm@linux-foundation.org, arnd@arndb.de Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, x86@kernel.org, linux-nvdimm@lists.01.org, jgross@suse.com, stefan.bader@canonical.com, luto@amacapital.net, hmh@hmh.eng.br, yigal@plexistor.com, konrad.wilk@oracle.com, Elliott@hp.com, mcgrof@suse.com, hch@lst.de, Toshi Kani 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; -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org