Extern or forward variable declaration include/linux/bpf.h, line 42 [usage...] include/linux/fsnotify_backend.h, line 113 [usage...] include/linux/ksm.h, line 19 [usage...] include/linux/list_lru.h, line 15 [usage...] include/linux/memcontrol.h, line 25 [usage...] include/linux/memcontrol.h, line 1071 [usage...] include/linux/mm_types.h, line 29 [usage...] include/linux/oom.h, line 15 [usage...] include/linux/slab.h, line 138 [usage...] include/linux/vmpressure.h, line 30 [usage...] Structure include/linux/memcontrol.h, line 221 [usage...]