Commits
Douglas Gilbert committed cbf67842c3d
scsi_debug: support scsi-mq, queues and locks - add host_lock option whose default value is 0 which removes the host_lock around all queued commands - accept delay=-1 (_hi_) or -2 which use a tasklet to invoke the scsi_done callback into the mid-layer. The default is still delay=1 which uses a timer to delay 1 jiffy - wire .change_queue_depth and .change_queue_type functions to better simulate queueing in a modern LLD - add SCSI_DEBUG_OPT_Q_NOISE (0x200) mask to only produce debug output associated with queue full, plus from .change_queue_depth and .change_queue_type functions - add SCSI_DEBUG_OPT_ALL_TSF (0x400) mask which reports all queued_arr fulls at TASK_SET_FULL, otherwise SCSI_MLQUEUE_HOST_BUSY is returned - add SCSI_DEBUG_OPT_RARE_TSF (0x800) mask which works together with the every_nth option (> 0) to count occurrences of num_in_q==queue_depth. When every_nth is reached the victim (a command) yields TASK SET FULL - clean up many debug messages. - add ndelay=<nanosecs> option that uses high resolution timers; active if > 0 and then overrides delay= option - expand Unit Attention handling: POR, BUS_RESET and MODE PARAMETERS CHANGED - support .eh_target_reset_handler and drop .bios_param - add OPT_N_WCE mask so caching page yields WCE=0 - add OPT_RESET_NOISE mask to log aborts and resets - add OPT_NO_CDB_NOISE mask to not log each cdb - MODE SELECT support for changing caching page's WCE - name common ioctls in log - when fake_rw=1, do not vmalloc fake store; make UNMAP and WRITE SAME obey fake_rw - more logging and code improvements including better sense buffer handling With fio and four (pseudo) devices I have observed 1.2 M IOPS on my equipment. Rob Elliott who has done much testing and made numerous suggestions, has better IOPS results than mine. Signed-off-by: Douglas Gilbert <dgilbert@interlog.com> Reviewed-by: Robert Elliott <elliott@hp.com> Tested-by: Robert Elliott <elliott@hp.com> Signed-off-by: Christoph Hellwig <hch@lst.de>