scsi: convert target_busy to an atomic_t

Avoid taking the host-wide host_lock to check the per-target queue limit.
Instead we do an atomic_inc_return early on to grab our slot in the queue,
and if necessary decrement it after finishing all checks.

Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Martin K. Petersen <[email protected]>
Reviewed-by: Hannes Reinecke <[email protected]>
Reviewed-by: Webb Scales <[email protected]>
Acked-by: Jens Axboe <[email protected]>
Tested-by: Bart Van Assche <[email protected]>
Tested-by: Robert Elliott <[email protected]>

0 files changed, 0 insertions, 0 deletions