Function prototype or declaration at include/linux/backing-dev.h, line 504 References: block/bfq-iosched.c, line 4981 block/blk-cgroup.c, line 499 fs/ceph/debugfs.c, line 360 fs/fs-writeback.c, line 2066 fs/fs-writeback.c, line 2323 include/linux/backing-dev.h, line 504 include/trace/events/writeback.h, line 69 include/trace/events/writeback.h, line 113 include/trace/events/writeback.h, line 194 include/trace/events/writeback.h, line 223 include/trace/events/writeback.h, line 256 include/trace/events/writeback.h, line 289 include/trace/events/writeback.h, line 319 include/trace/events/writeback.h, line 362 include/trace/events/writeback.h, line 415 include/trace/events/writeback.h, line 437 include/trace/events/writeback.h, line 462 include/trace/events/writeback.h, line 513 include/trace/events/writeback.h, line 596 include/trace/events/writeback.h, line 661 include/trace/events/writeback.h, line 722 include/trace/events/writeback.h, line 796 mm/backing-dev.c, line 1036 mm/backing-dev.c, line 1042