[SCSI] lpfc 8.3.33: Add Interrupts per second stats via debugfs

Signed-off-by: James Smart <james.smart@emulex.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index 982bd40..83a1c9e 100644
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -2825,10 +2825,26 @@
 void lpfc_poll_eratt(unsigned long ptr)
 {
 	struct lpfc_hba *phba;
-	uint32_t eratt = 0;
+	uint32_t eratt = 0, rem;
+	uint64_t sli_intr, cnt;
 
 	phba = (struct lpfc_hba *)ptr;
 
+	/* Here we will also keep track of interrupts per sec of the hba */
+	sli_intr = phba->sli.slistat.sli_intr;
+
+	if (phba->sli.slistat.sli_prev_intr > sli_intr)
+		cnt = (((uint64_t)(-1) - phba->sli.slistat.sli_prev_intr) +
+			sli_intr);
+	else
+		cnt = (sli_intr - phba->sli.slistat.sli_prev_intr);
+
+	/* 64-bit integer division not supporte on 32-bit x86 - use do_div */
+	rem = do_div(cnt, LPFC_ERATT_POLL_INTERVAL);
+	phba->sli.slistat.sli_ips = cnt;
+
+	phba->sli.slistat.sli_prev_intr = sli_intr;
+
 	/* Check chip HA register for error event */
 	eratt = lpfc_sli_check_eratt(phba);