![]() Careful analysis shows that this flag is not needed. The RESCUER flag is only needed when a make_request_fn might: - allocate a bio from the bioset - submit it with generic_make_request() or similar - allocate another bio from the bioset The second allocation can block until the first bio is processed, so a rescuer is needed to ensure the first bio does get processed. With a rescuer it will only get processed when the make_request_fn completes. In drbd, allocations from drbd_io_bio_set happen from drbd_new_req() or w_restart_disk_io() which is only called to handle RESTART_FROZEN_DISK_IO. In former is called precisely once from the make_request_fn. The later is never called by within the make_request_fn. So there cannot be two allocations in the same call to the make_request_fn, so a rescuer is not needed. Allocations from drbd_md_io_bio_set are used for IO to the bitmap and the activity log. There are only accessed from worker threads and workqueues, never directly from make_request_fn. Again, the rescuer isn't needed. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> |
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.. | ||
drbd_actlog.c | ||
drbd_bitmap.c | ||
drbd_debugfs.c | ||
drbd_debugfs.h | ||
drbd_int.h | ||
drbd_interval.c | ||
drbd_interval.h | ||
drbd_main.c | ||
drbd_nl.c | ||
drbd_nla.c | ||
drbd_nla.h | ||
drbd_proc.c | ||
drbd_protocol.h | ||
drbd_receiver.c | ||
drbd_req.c | ||
drbd_req.h | ||
drbd_state.c | ||
drbd_state.h | ||
drbd_state_change.h | ||
drbd_strings.c | ||
drbd_strings.h | ||
drbd_vli.h | ||
drbd_worker.c | ||
Kconfig | ||
Makefile |