block_bio_merge 290 include/trace/events/block.h DECLARE_EVENT_CLASS(block_bio_merge, block_bio_merge 327 include/trace/events/block.h DEFINE_EVENT(block_bio_merge, block_bio_backmerge, block_bio_merge 343 include/trace/events/block.h DEFINE_EVENT(block_bio_merge, block_bio_frontmerge,