Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753594AbdF2SDl (ORCPT ); Thu, 29 Jun 2017 14:03:41 -0400 Received: from mga05.intel.com ([192.55.52.43]:28195 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753302AbdF2SAC (ORCPT ); Thu, 29 Jun 2017 14:00:02 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.40,282,1496127600"; d="scan'208";a="1146184667" Subject: [PATCH v4 07/16] x86, dax: replace clear_pmem() with open coded memset + dax_ops->flush From: Dan Williams To: linux-nvdimm@lists.01.org Cc: Jan Kara , Matthew Wilcox , x86@kernel.org, linux-kernel@vger.kernel.org, hch@lst.de, Jeff Moyer , Ingo Molnar , viro@zeniv.linux.org.uk, "H. Peter Anvin" , linux-fsdevel@vger.kernel.org, Thomas Gleixner , Ross Zwisler Date: Thu, 29 Jun 2017 10:53:34 -0700 Message-ID: <149875881481.10031.13878353933320037524.stgit@dwillia2-desk3.amr.corp.intel.com> In-Reply-To: <149875877608.10031.17813337234536358002.stgit@dwillia2-desk3.amr.corp.intel.com> References: <149875877608.10031.17813337234536358002.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.17.1-9-g687f MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3146 Lines: 101 The clear_pmem() helper simply combines a memset() plus a cache flush. Now that the flush routine is optionally provided by the dax device driver we can avoid unnecessary cache management on dax devices fronting volatile memory. With clear_pmem() gone we can follow on with a patch to make pmem cache management completely defined within the pmem driver. Cc: Cc: Jeff Moyer Cc: Ingo Molnar Cc: Christoph Hellwig Cc: "H. Peter Anvin" Cc: Thomas Gleixner Cc: Matthew Wilcox Cc: Ross Zwisler Reviewed-by: Jan Kara Signed-off-by: Dan Williams --- arch/x86/include/asm/pmem.h | 13 ------------- fs/dax.c | 3 ++- include/linux/pmem.h | 21 --------------------- 3 files changed, 2 insertions(+), 35 deletions(-) diff --git a/arch/x86/include/asm/pmem.h b/arch/x86/include/asm/pmem.h index 60e8edbe0205..f4c119d253f3 100644 --- a/arch/x86/include/asm/pmem.h +++ b/arch/x86/include/asm/pmem.h @@ -65,19 +65,6 @@ static inline void arch_wb_cache_pmem(void *addr, size_t size) clwb(p); } -/** - * arch_clear_pmem - zero a PMEM memory range - * @addr: virtual start address - * @size: number of bytes to zero - * - * Write zeros into the memory range starting at 'addr' for 'size' bytes. - */ -static inline void arch_clear_pmem(void *addr, size_t size) -{ - memset(addr, 0, size); - arch_wb_cache_pmem(addr, size); -} - static inline void arch_invalidate_pmem(void *addr, size_t size) { clflush_cache_range(addr, size); diff --git a/fs/dax.c b/fs/dax.c index 0933fc460ada..554b8e7d921c 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -975,7 +975,8 @@ int __dax_zero_page_range(struct block_device *bdev, dax_read_unlock(id); return rc; } - clear_pmem(kaddr + offset, size); + memset(kaddr + offset, 0, size); + dax_flush(dax_dev, pgoff, kaddr + offset, size); dax_read_unlock(id); } return 0; diff --git a/include/linux/pmem.h b/include/linux/pmem.h index 9d542a5600e4..772bd02a5b52 100644 --- a/include/linux/pmem.h +++ b/include/linux/pmem.h @@ -31,11 +31,6 @@ static inline void arch_memcpy_to_pmem(void *dst, const void *src, size_t n) BUG(); } -static inline void arch_clear_pmem(void *addr, size_t size) -{ - BUG(); -} - static inline void arch_wb_cache_pmem(void *addr, size_t size) { BUG(); @@ -73,22 +68,6 @@ static inline void memcpy_to_pmem(void *dst, const void *src, size_t n) } /** - * clear_pmem - zero a PMEM memory range - * @addr: virtual start address - * @size: number of bytes to zero - * - * Write zeros into the memory range starting at 'addr' for 'size' bytes. - * See blkdev_issue_flush() note for memcpy_to_pmem(). - */ -static inline void clear_pmem(void *addr, size_t size) -{ - if (arch_has_pmem_api()) - arch_clear_pmem(addr, size); - else - memset(addr, 0, size); -} - -/** * invalidate_pmem - flush a pmem range from the cache hierarchy * @addr: virtual start address * @size: bytes to invalidate (internally aligned to cache line size)