Commit 05116ef9 authored by James Smart's avatar James Smart Committed by Martin K. Petersen
Browse files

scsi: lpfc: Cap CMF read bytes to MBPI 

Ensure read bytes data does not go over MBPI for CMF timer intervals that
are purposely shortened.

Link: https://lore.kernel.org/r/20211204002644.116455-8-jsmart2021@gmail.com


Co-developed-by: default avatarJustin Tee <justin.tee@broadcom.com>
Signed-off-by: default avatarJustin Tee <justin.tee@broadcom.com>
Signed-off-by: default avatarJames Smart <jsmart2021@gmail.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent a6269f83

drivers/scsi/lpfc/lpfc.h

+1 −1
Original line number Diff line number Diff line
@@ -1028,7 +1028,7 @@ struct lpfc_hba { 
					 */

#define HBA_PCI_ERR		0x80000 /* The PCI slot is offline */

#define HBA_FLOGI_ISSUED	0x100000 /* FLOGI was issued */

#define HBA_CGN_RSVD1		0x200000 /* Reserved CGN flag */

#define HBA_SHORT_CMF		0x200000 /* shorter CMF timer routine */

#define HBA_CGN_DAY_WRAP	0x400000 /* HBA Congestion info day wraps */

#define HBA_DEFER_FLOGI		0x800000 /* Defer FLOGI till read_sparm cmpl */

#define HBA_SETUP		0x1000000 /* Signifies HBA setup is completed */

drivers/scsi/lpfc/lpfc_init.c

+10 −1
Original line number Diff line number Diff line
@@ -6004,8 +6004,13 @@ lpfc_cmf_timer(struct hrtimer *timer) 
		if (ms && ms < LPFC_CMF_INTERVAL) {

			cnt = div_u64(total, ms); /* bytes per ms */

			cnt *= LPFC_CMF_INTERVAL; /* what total should be */

			if (cnt > mbpi)



			/* If the timeout is scheduled to be shorter,

			 * this value may skew the data, so cap it at mbpi.

			 */

			if ((phba->hba_flag & HBA_SHORT_CMF) && cnt > mbpi)

				cnt = mbpi;



			extra = cnt - total;

		}

		lpfc_issue_cmf_sync_wqe(phba, LPFC_CMF_INTERVAL, total + extra);
@@ -6088,6 +6093,8 @@ lpfc_cmf_timer(struct hrtimer *timer) 
	/* Each minute save Fabric and Driver congestion information */

	lpfc_cgn_save_evt_cnt(phba);



	phba->hba_flag &= ~HBA_SHORT_CMF;



	/* Since we need to call lpfc_cgn_save_evt_cnt every minute, on the

	 * minute, adjust our next timer interval, if needed, to ensure a

	 * 1 minute granularity when we get the next timer interrupt.
@@ -6098,6 +6105,8 @@ lpfc_cmf_timer(struct hrtimer *timer) 
						  jiffies);

		if (timer_interval <= 0)

			timer_interval = LPFC_CMF_INTERVAL;

		else

			phba->hba_flag |= HBA_SHORT_CMF;



		/* If we adjust timer_interval, max_bytes_per_interval

		 * needs to be adjusted as well.