bdi: make backing_dev_info->wb.dwork canceling stricter
Canceling of bdi->wb.dwork is currently a bit mushy. bdi_wb_shutdown() performs cancel_delayed_work_sync() at the end after shutting down and flushing the delayed_work and bdi_destroy() tries yet again after bdi_unregister(). bdi->wb.dwork is queued only after checking BDI_registered while holding bdi->wb_lock and bdi_wb_shutdown() clears the flag while holding the same lock and then flushes the delayed_work. There's no way the delayed_work can be queued again after that. Replace the two unnecessary cancel_delayed_work_sync() invocations with WARNs on pending. This simplifies and clarifies the code a bit and will help future changes in further isolating bdi_writeback handling. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@fb.com>
Please register or sign in to comment