There are several functions that take a generic get_extent parameter, but not all of them use it to distinguish between btree_get_exnent (for metadata) and btrfs_get_extent (for data). This is namely extent_read_full_page and __do_readpage. The rest can be cleaned up so that the desired get_extent callback is used directly. The patchset does that incrementally so each change is clear. The difference in binary code size is not that impressive: text data bss dec hex filename 985353 75124 18560 1079037 1076fd pre/btrfs.ko 985193 75124 18560 1078877 10765d post/btrfs.ko but the estimated stack consumption savings are about 64 bytes, and it could be more if we calculate cummulative effect when more than one reduced function is in the callchain: -extent_io.c:btree_write_cache_pages 288 static +extent_io.c:btree_write_cache_pages 280 static -extent_io.c:extent_fiemap 264 dynamic,bounded +extent_io.c:extent_fiemap 256 dynamic,bounded -extent_io.c:extent_readpages 264 dynamic,bounded +extent_io.c:extent_readpages 248 dynamic,bounded -extent_io.c:extent_write_full_page 56 static +extent_io.c:extent_write_full_page 48 static -extent_io.c:extent_write_locked_range 200 static +extent_io.c:extent_write_locked_range 192 static -extent_io.c:extent_writepages 56 static +extent_io.c:extent_writepages 48 static -extent_io.c:get_extent_skip_holes 64 static +extent_io.c:get_extent_skip_holes 56 static (calculated with gcc -fstack-usage) David Sterba (10): btrfs: sink get_extent parameter to extent_writepages btrfs: sink get_extent parameter to extent_write_locked_range btrfs: sink get_extent parameter to extent_write_full_page btrfs: drop get_extent from extent_page_data btrfs: sink get_extent parameter to extent_fiemap btrfs: sink get_extent parameter to get_extent_skip_holes btrfs: sink get_extent parameter to extent_readpages btrfs: sink get_extent parameter to __extent_readpages btrfs: sink get_extent parameter to __do_contiguous_readpages btrfs: sink get_extent parameter to read_extent_buffer_pages fs/btrfs/disk-io.c | 8 ++++---- fs/btrfs/disk-io.h | 3 +++ fs/btrfs/extent_io.c | 55 ++++++++++++++++++++-------------------------------- fs/btrfs/extent_io.h | 12 ++++-------- fs/btrfs/inode.c | 10 ++++------ 5 files changed, 36 insertions(+), 52 deletions(-) -- 2.14.3 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
