From 81f558701ae8d5677635118751b1b4043094c7e9 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Mon, 29 May 2017 13:12:20 -0700 Subject: [PATCH] x86, dax: replace clear_pmem() with open coded memset + dax_ops->flush 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(); @@ -72,22 +67,6 @@ static inline void memcpy_to_pmem(void *dst, const void *src, size_t n) memcpy(dst, src, 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 -- 2.20.1