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>
This commit is contained in:

committed by
Linus Torvalds

parent
bdbd01ac44
commit
f281233d3e
@@ -430,7 +430,7 @@ static int uas_submit_urbs(struct scsi_cmnd *cmnd,
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int uas_queuecommand(struct scsi_cmnd *cmnd,
|
||||
static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
|
||||
void (*done)(struct scsi_cmnd *))
|
||||
{
|
||||
struct scsi_device *sdev = cmnd->device;
|
||||
@@ -488,6 +488,8 @@ static int uas_queuecommand(struct scsi_cmnd *cmnd,
|
||||
return 0;
|
||||
}
|
||||
|
||||
static DEF_SCSI_QCMD(uas_queuecommand)
|
||||
|
||||
static int uas_eh_abort_handler(struct scsi_cmnd *cmnd)
|
||||
{
|
||||
struct scsi_device *sdev = cmnd->device;
|
||||
|
Reference in New Issue
Block a user