From a6eb3c9f73deaa318f17a19c7ad012b3ebe750c3 Mon Sep 17 00:00:00 2001 From: Chetan Loke Date: Tue, 15 May 2012 14:34:09 -0400 Subject: [PATCH] [SCSI] qla2xxx: Micro optimization in queuecommand handler Optimized queuecommand handler's to eliminate double head-room checks. The checks are moved inside the 1st if-loop otherwise you would end up checking twice when there is enough head room. Signed-off-by: Chetan Loke Reviewed-by: Andrew Vasquez Reviewed-by: Giridhar Malavali Signed-off-by: Chad Dupuis Signed-off-by: James Bottomley --- drivers/scsi/qla2xxx/qla_iocb.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/drivers/scsi/qla2xxx/qla_iocb.c b/drivers/scsi/qla2xxx/qla_iocb.c index eac950924497..1ae0d1dbbdb4 100644 --- a/drivers/scsi/qla2xxx/qla_iocb.c +++ b/drivers/scsi/qla2xxx/qla_iocb.c @@ -385,9 +385,10 @@ qla2x00_start_scsi(srb_t *sp) else req->cnt = req->length - (req->ring_index - cnt); + /* If still no head room then bail out */ + if (req->cnt < (req_cnt + 2)) + goto queuing_error; } - if (req->cnt < (req_cnt + 2)) - goto queuing_error; /* Build command packet */ req->current_outstanding_cmd = handle; @@ -1502,9 +1503,9 @@ qla24xx_start_scsi(srb_t *sp) else req->cnt = req->length - (req->ring_index - cnt); + if (req->cnt < (req_cnt + 2)) + goto queuing_error; } - if (req->cnt < (req_cnt + 2)) - goto queuing_error; /* Build command packet. */ req->current_outstanding_cmd = handle; @@ -1717,11 +1718,10 @@ qla24xx_dif_start_scsi(srb_t *sp) else req->cnt = req->length - (req->ring_index - cnt); + if (req->cnt < (req_cnt + 2)) + goto queuing_error; } - if (req->cnt < (req_cnt + 2)) - goto queuing_error; - status |= QDSS_GOT_Q_SPACE; /* Build header part of command packet (excluding the OPCODE). */ @@ -2343,11 +2343,10 @@ sufficient_dsds: else req->cnt = req->length - (req->ring_index - cnt); + if (req->cnt < (req_cnt + 2)) + goto queuing_error; } - if (req->cnt < (req_cnt + 2)) - goto queuing_error; - ctx = sp->u.scmd.ctx = mempool_alloc(ha->ctx_mempool, GFP_ATOMIC); if (!ctx) { -- 2.39.5