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1dd55358ef
f2fs_copy_page() is a wrapper around two kmap() + one memcpy() from/to the mapped pages. It unnecessarily duplicates a kernel API and it makes use of kmap(), which is being deprecated in favor of kmap_local_page(). Two main problems with kmap(): (1) It comes with an overhead as mapping space is restricted and protected by a global lock for synchronization and (2) it also requires global TLB invalidation when the kmap’s pool wraps and it might block when the mapping space is fully utilized until a slot becomes available. With kmap_local_page() the mappings are per thread, CPU local, can take page faults, and can be called from any context (including interrupts). It is faster than kmap() in kernels with HIGHMEM enabled. Therefore, its use in __clone_blkaddrs() is safe and should be preferred. Delete f2fs_copy_page() and use a plain memcpy_page() in the only one site calling the removed function. memcpy_page() avoids open coding two kmap_local_page() + one memcpy() between the two kernel virtual addresses. Suggested-by: Christoph Hellwig <hch@infradead.org> Suggested-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> |
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| .. | ||
| acl.c | ||
| acl.h | ||
| checkpoint.c | ||
| compress.c | ||
| data.c | ||
| debug.c | ||
| dir.c | ||
| extent_cache.c | ||
| f2fs.h | ||
| file.c | ||
| gc.c | ||
| gc.h | ||
| hash.c | ||
| inline.c | ||
| inode.c | ||
| iostat.c | ||
| iostat.h | ||
| Kconfig | ||
| Makefile | ||
| namei.c | ||
| node.c | ||
| node.h | ||
| recovery.c | ||
| segment.c | ||
| segment.h | ||
| shrinker.c | ||
| super.c | ||
| sysfs.c | ||
| verity.c | ||
| xattr.c | ||
| xattr.h | ||