Commit 22770cba authored by James Smart's avatar James Smart Committed by Martin K. Petersen
Browse files

scsi: lpfc: Slight fast-path performance optimizations 

Slightly rework some error check code paths for better streamlining.

Added compiler unlikely hints to allow slightly better optimization of the
fast-path.

Removed a few pointer checks that were obviously already valid.

Link: https://lore.kernel.org/r/20191018211832.7917-9-jsmart2021@gmail.com


Signed-off-by: default avatarDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: default avatarJames Smart <jsmart2021@gmail.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent f84f8f93

drivers/scsi/lpfc/lpfc_nvme.c

+1 −1
Original line number Diff line number Diff line
@@ -2093,7 +2093,7 @@ lpfc_release_nvme_buf(struct lpfc_hba *phba, struct lpfc_io_buf *lpfc_ncmd) 
	lpfc_ncmd->flags &= ~LPFC_SBUF_BUMP_QDEPTH;



	qp = lpfc_ncmd->hdwq;

	if (lpfc_ncmd->flags & LPFC_SBUF_XBUSY) {

	if (unlikely(lpfc_ncmd->flags & LPFC_SBUF_XBUSY)) {

		lpfc_printf_log(phba, KERN_INFO, LOG_NVME_ABTS,

				"6310 XB release deferred for "

				"ox_id x%x on reqtag x%x\n",

drivers/scsi/lpfc/lpfc_scsi.c

+9 −8
Original line number Diff line number Diff line
@@ -611,7 +611,7 @@ lpfc_get_scsi_buf_s3(struct lpfc_hba *phba, struct lpfc_nodelist *ndlp, 
	}

	spin_unlock_irqrestore(&phba->scsi_buf_list_get_lock, iflag);



	if (lpfc_ndlp_check_qdepth(phba, ndlp) && lpfc_cmd) {

	if (lpfc_ndlp_check_qdepth(phba, ndlp)) {

		atomic_inc(&ndlp->cmd_pending);

		lpfc_cmd->flags |= LPFC_SBUF_BUMP_QDEPTH;

	}
@@ -3826,7 +3826,7 @@ lpfc_scsi_cmd_iocb_cmpl(struct lpfc_hba *phba, struct lpfc_iocbq *pIocbIn, 
		phba->sli4_hba.hdwq[idx].scsi_cstat.io_cmpls++;



#ifdef CONFIG_SCSI_LPFC_DEBUG_FS

	if (phba->cpucheck_on & LPFC_CHECK_SCSI_IO) {

	if (unlikely(phba->cpucheck_on & LPFC_CHECK_SCSI_IO)) {

		cpu = raw_smp_processor_id();

		if (cpu < LPFC_CHECK_CPU_CNT && phba->sli4_hba.hdwq)

			phba->sli4_hba.hdwq[idx].cpucheck_cmpl_io[cpu]++;
@@ -3874,7 +3874,7 @@ lpfc_scsi_cmd_iocb_cmpl(struct lpfc_hba *phba, struct lpfc_iocbq *pIocbIn, 
	}

#endif



	if (lpfc_cmd->status) {

	if (unlikely(lpfc_cmd->status)) {

		if (lpfc_cmd->status == IOSTAT_LOCAL_REJECT &&

		    (lpfc_cmd->result & IOERR_DRVR_MASK))

			lpfc_cmd->status = IOSTAT_DRIVER_REJECT;
@@ -4615,17 +4615,18 @@ lpfc_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *cmnd) 
		err = lpfc_scsi_prep_dma_buf(phba, lpfc_cmd);

	}



	if (unlikely(err)) {

		if (err == 2) {

			cmnd->result = DID_ERROR << 16;

			goto out_fail_command_release_buf;

	} else if (err) {

		}

		goto out_host_busy_free_buf;

	}



	lpfc_scsi_prep_cmnd(vport, lpfc_cmd, ndlp);



#ifdef CONFIG_SCSI_LPFC_DEBUG_FS

	if (phba->cpucheck_on & LPFC_CHECK_SCSI_IO) {

	if (unlikely(phba->cpucheck_on & LPFC_CHECK_SCSI_IO)) {

		cpu = raw_smp_processor_id();

		if (cpu < LPFC_CHECK_CPU_CNT) {

			struct lpfc_sli4_hdw_queue *hdwq =

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