kernel-ark/drivers/s390
Jeff Garzik f281233d3e SCSI host lock push-down
Move the mid-layer's ->queuecommand() invocation from being locked
with the host lock to being unlocked to facilitate speeding up the
critical path for drivers who don't need this lock taken anyway.

The patch below presents a simple SCSI host lock push-down as an
equivalent transformation.  No locking or other behavior should change
with this patch.  All existing bugs and locking orders are preserved.

Additionally, add one parameter to queuecommand,
	struct Scsi_Host *
and remove one parameter from queuecommand,
	void (*done)(struct scsi_cmnd *)

Scsi_Host* is a convenient pointer that most host drivers need anyway,
and 'done' is redundant to struct scsi_cmnd->scsi_done.

Minimal code disturbance was attempted with this change.  Most drivers
needed only two one-line modifications for their host lock push-down.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Acked-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-16 13:33:23 -08:00
..
block [S390] dasd: provide a Sense Path Group ID ioctl 2010-10-29 16:50:50 +02:00
char [S390] vmlogrdr: purge after recording is switched off 2010-11-10 10:05:54 +01:00
cio [S390] cio: fix incorrect ccw_device_init_count 2010-11-10 10:05:54 +01:00
crypto [S390] cleanup facility list handling 2010-10-25 16:10:21 +02:00
kvm [S390] cleanup lowcore access from external interrupts 2010-10-25 16:10:19 +02:00
net qeth: fix race condition during device startup 2010-11-08 12:17:08 -08:00
scsi SCSI host lock push-down 2010-11-16 13:33:23 -08:00
Makefile