From f281233d3eba15fb225d21ae2e228fd4553d824a Mon Sep 17 00:00:00 2001 From: Jeff Garzik Date: Tue, 16 Nov 2010 02:10:29 -0500 Subject: 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 Acked-by: James Bottomley Signed-off-by: Linus Torvalds --- drivers/scsi/ips.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'drivers/scsi/ips.c') diff --git a/drivers/scsi/ips.c b/drivers/scsi/ips.c index f83a116..b2511ac 100644 --- a/drivers/scsi/ips.c +++ b/drivers/scsi/ips.c @@ -232,7 +232,7 @@ static int ips_detect(struct scsi_host_template *); static int ips_release(struct Scsi_Host *); static int ips_eh_abort(struct scsi_cmnd *); static int ips_eh_reset(struct scsi_cmnd *); -static int ips_queue(struct scsi_cmnd *, void (*)(struct scsi_cmnd *)); +static int ips_queue(struct Scsi_Host *, struct scsi_cmnd *); static const char *ips_info(struct Scsi_Host *); static irqreturn_t do_ipsintr(int, void *); static int ips_hainit(ips_ha_t *); @@ -1046,7 +1046,7 @@ static int ips_eh_reset(struct scsi_cmnd *SC) /* Linux obtains io_request_lock before calling this function */ /* */ /****************************************************************************/ -static int ips_queue(struct scsi_cmnd *SC, void (*done) (struct scsi_cmnd *)) +static int ips_queue_lck(struct scsi_cmnd *SC, void (*done) (struct scsi_cmnd *)) { ips_ha_t *ha; ips_passthru_t *pt; @@ -1137,6 +1137,8 @@ static int ips_queue(struct scsi_cmnd *SC, void (*done) (struct scsi_cmnd *)) return (0); } +static DEF_SCSI_QCMD(ips_queue) + /****************************************************************************/ /* */ /* Routine Name: ips_biosparam */ -- cgit v1.1