blk_add_trace_bio_backmerge 1130 kernel/trace/blktrace.c 	ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL);
blk_add_trace_bio_backmerge 1163 kernel/trace/blktrace.c 	unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge, NULL);