Extern or forward variable declaration at include/linux/workqueue.h, line 388 References: drivers/block/zram/zram_drv.c, line 811 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c, line 3986 drivers/gpu/drm/drm_atomic_helper.c, line 1859 drivers/gpu/drm/i915/display/intel_display_power.c, line 2205 drivers/gpu/drm/i915/i915_active.c, line 183 drivers/gpu/drm/i915/i915_sw_fence_work.c, line 44 drivers/gpu/drm/nouveau/dispnv50/disp.c, line 2203 drivers/gpu/drm/rockchip/rockchip_drm_vop.c, line 1658 drivers/gpu/drm/vc4/vc4_kms.c, line 295 drivers/infiniband/core/device.c, line 1581 drivers/infiniband/core/device.c, line 2803 drivers/infiniband/hw/mlx5/odp.c, line 258 drivers/infiniband/hw/mlx5/odp.c, line 1869 drivers/scsi/qla2xxx/qla_os.c, line 5029 drivers/scsi/scsi_transport_iscsi.c, line 2524 drivers/soc/xilinx/zynqmp_power.c, line 100 drivers/staging/fwserial/fwserial.c, line 2644 drivers/staging/fwserial/fwserial.c, line 2673 drivers/target/sbp/sbp_target.c, line 733 drivers/target/sbp/sbp_target.c, line 767 drivers/target/sbp/sbp_target.c, line 993 drivers/target/sbp/sbp_target.c, line 1624 drivers/tty/tty_buffer.c, line 75 drivers/tty/tty_buffer.c, line 413 drivers/tty/tty_buffer.c, line 608 fs/btrfs/space-info.c, line 1279 fs/btrfs/space-info.c, line 1298 fs/notify/mark.c, line 265 fs/notify/mark.c, line 276 include/linux/workqueue.h, line 388 kernel/async.c, line 212 kernel/padata.c, line 545 kernel/sched/core.c, line 3793 kernel/sched/core.c, line 3812 kernel/umh.c, line 590 kernel/workqueue.c, line 348 kernel/workqueue.c, line 349 kernel/workqueue.c, line 5968 kernel/workqueue.c, line 5978 lib/vsprintf.c, line 733 sound/soc/codecs/wm_adsp.c, line 3164