FCF failover improvements
- Add random FCF failover when there are multiple FCFs available.
- Prevent FCF log messages from being displayed for FC adapters.
- Separate the New FCF and Modified FCF log messages.
Signed-off-by: Alex Iannicelli <alex.iannicelli@xxxxxxxxxx>
Signed-off-by: James Smart <james.smart@xxxxxxxxxx>
---
lpfc_els.c | 13 ++++++++-----
lpfc_hbadisc.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++--
lpfc_init.c | 19 ++++++++++++++-----
lpfc_sli.c | 4 +++-
lpfc_sli4.h | 1 +
5 files changed, 77 insertions(+), 13 deletions(-)
diff -upNr a/drivers/scsi/lpfc/lpfc_els.c b/drivers/scsi/lpfc/lpfc_els.c
--- a/drivers/scsi/lpfc/lpfc_els.c 2010-03-05 10:42:37.000000000 -0500
+++ b/drivers/scsi/lpfc/lpfc_els.c 2010-03-15 10:30:47.000000000 -0400
@@ -892,11 +892,14 @@ lpfc_cmpl_els_flogi(struct lpfc_hba *phb
if (!rc) {
/* Mark the FCF discovery process done */
- lpfc_printf_vlog(vport, KERN_INFO, LOG_FIP | LOG_ELS,
- "2769 FLOGI successful on FCF record: "
- "current_fcf_index:x%x, terminate FCF "
- "round robin failover process\n",
- phba->fcf.current_rec.fcf_indx);
+ if (phba->hba_flag & HBA_FIP_SUPPORT)
+ lpfc_printf_vlog(vport, KERN_INFO, LOG_FIP |
+ LOG_ELS,
+ "2769 FLOGI successful on FCF "
+ "record: current_fcf_index:"
+ "x%x, terminate FCF round "
+ "robin failover process\n",
+ phba->fcf.current_rec.fcf_indx);
spin_lock_irq(&phba->hbalock);
phba->fcf.fcf_flag &= ~FCF_DISCOVERY;
spin_unlock_irq(&phba->hbalock);
diff -upNr a/drivers/scsi/lpfc/lpfc_hbadisc.c b/drivers/scsi/lpfc/lpfc_hbadisc.c
--- a/drivers/scsi/lpfc/lpfc_hbadisc.c 2010-03-05 10:42:37.000000000 -0500
+++ b/drivers/scsi/lpfc/lpfc_hbadisc.c 2010-03-15 10:30:47.000000000 -0400
@@ -1530,7 +1530,37 @@ lpfc_check_pending_fcoe_event(struct lpf
}
/**
- * lpfc_sli4_fcf_rec_mbox_parse - parse non-embedded fcf record mailbox command
+ * lpfc_sli4_new_fcf_random_select - Randomly select an eligible new fcf record
+ * @phba: pointer to lpfc hba data structure.
+ * @fcf_cnt: number of eligible fcf record seen so far.
+ *
+ * This function makes an running random selection decision on FCF record to
+ * use through a sequence of @fcf_cnt eligible FCF records with equal
+ * probability. To perform integer manunipulation of random numbers with
+ * size unit32_t, the lower 16 bits of the 32-bit random number returned
+ * from random32() are taken as the random random number generated.
+ *
+ * Returns true when outcome is for the newly read FCF record should be
+ * chosen; otherwise, return false when outcome is for keeping the previously
+ * chosen FCF record.
+ **/
+static bool
+lpfc_sli4_new_fcf_random_select(struct lpfc_hba *phba, uint32_t fcf_cnt)
+{
+ uint32_t rand_num;
+
+ /* Get 16-bit uniform random number */
+ rand_num = (0xFFFF & random32());
+
+ /* Decision with probability 1/fcf_cnt */
+ if ((fcf_cnt * rand_num) < 0xFFFF)
+ return true;
+ else
+ return false;
+}
+
+/**
+ * lpfc_mbx_cmpl_read_fcf_record - Completion handler for read_fcf mbox.
* @phba: pointer to lpfc hba data structure.
* @mboxq: pointer to mailbox object.
* @next_fcf_index: pointer to holder of next fcf index.
@@ -1678,6 +1708,8 @@ lpfc_mbx_cmpl_fcf_scan_read_fcf_rec(stru
uint16_t fcf_index, next_fcf_index;
struct lpfc_fcf_rec *fcf_rec = NULL;
uint16_t vlan_id;
+ uint32_t seed;
+ bool select_new_fcf;
int rc;
/* If there is pending FCoE event restart FCF table scan */
@@ -1808,9 +1840,21 @@ lpfc_mbx_cmpl_fcf_scan_read_fcf_rec(stru
* than the driver FCF record, use the new record.
*/
if (new_fcf_record->fip_priority < fcf_rec->priority) {
- /* Choose this FCF record */
+ /* Choose the new FCF record with lower priority */
__lpfc_update_fcf_record(phba, fcf_rec, new_fcf_record,
addr_mode, vlan_id, 0);
+ /* Reset running random FCF selection count */
+ phba->fcf.eligible_fcf_cnt = 1;
+ } else if (new_fcf_record->fip_priority == fcf_rec->priority) {
+ /* Update running random FCF selection count */
+ phba->fcf.eligible_fcf_cnt++;
+ select_new_fcf = lpfc_sli4_new_fcf_random_select(phba,
+ phba->fcf.eligible_fcf_cnt);
+ if (select_new_fcf)
+ /* Choose the new FCF by random selection */
+ __lpfc_update_fcf_record(phba, fcf_rec,
+ new_fcf_record,
+ addr_mode, vlan_id, 0);
}
spin_unlock_irq(&phba->hbalock);
goto read_next_fcf;
@@ -1824,6 +1868,11 @@ lpfc_mbx_cmpl_fcf_scan_read_fcf_rec(stru
addr_mode, vlan_id, (boot_flag ?
BOOT_ENABLE : 0));
phba->fcf.fcf_flag |= FCF_AVAILABLE;
+ /* Setup initial running random FCF selection count */
+ phba->fcf.eligible_fcf_cnt = 1;
+ /* Seeding the random number generator for random selection */
+ seed = (uint32_t)(0xFFFFFFFF & jiffies);
+ srandom32(seed);
}
spin_unlock_irq(&phba->hbalock);
goto read_next_fcf;
diff -upNr a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c
--- a/drivers/scsi/lpfc/lpfc_init.c 2010-03-05 10:42:37.000000000 -0500
+++ b/drivers/scsi/lpfc/lpfc_init.c 2010-03-15 10:30:47.000000000 -0400
@@ -3303,11 +3303,20 @@ lpfc_sli4_async_fcoe_evt(struct lpfc_hba
switch (event_type) {
case LPFC_FCOE_EVENT_TYPE_NEW_FCF:
case LPFC_FCOE_EVENT_TYPE_FCF_PARAM_MOD:
- lpfc_printf_log(phba, KERN_ERR, LOG_FIP | LOG_DISCOVERY,
- "2546 New FCF found/FCF parameter modified event: "
- "evt_tag:x%x, fcf_index:x%x\n",
- acqe_fcoe->event_tag, acqe_fcoe->index);
-
+ if (event_type == LPFC_FCOE_EVENT_TYPE_NEW_FCF)
+ lpfc_printf_log(phba, KERN_ERR, LOG_FIP |
+ LOG_DISCOVERY,
+ "2546 New FCF found event: "
+ "evt_tag:x%x, fcf_index:x%x\n",
+ acqe_fcoe->event_tag,
+ acqe_fcoe->index);
+ else
+ lpfc_printf_log(phba, KERN_WARNING, LOG_FIP |
+ LOG_DISCOVERY,
+ "2788 FCF parameter modified event: "
+ "evt_tag:x%x, fcf_index:x%x\n",
+ acqe_fcoe->event_tag,
+ acqe_fcoe->index);
spin_lock_irq(&phba->hbalock);
if ((phba->fcf.fcf_flag & FCF_SCAN_DONE) ||
(phba->hba_flag & FCF_DISC_INPROGRESS)) {
diff -upNr a/drivers/scsi/lpfc/lpfc_sli4.h b/drivers/scsi/lpfc/lpfc_sli4.h
--- a/drivers/scsi/lpfc/lpfc_sli4.h 2010-03-05 10:42:37.000000000 -0500
+++ b/drivers/scsi/lpfc/lpfc_sli4.h 2010-03-15 10:30:47.000000000 -0400
@@ -162,6 +162,7 @@ struct lpfc_fcf {
#define FCF_REDISC_FOV 0x200 /* Post FCF rediscovery fast failover */
uint32_t addr_mode;
uint16_t fcf_rr_init_indx;
+ uint32_t eligible_fcf_cnt;
struct lpfc_fcf_rec current_rec;
struct lpfc_fcf_rec failover_rec;
struct timer_list redisc_wait;
diff -upNr a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
--- a/drivers/scsi/lpfc/lpfc_sli.c 2010-03-05 10:42:37.000000000 -0500
+++ b/drivers/scsi/lpfc/lpfc_sli.c 2010-03-15 10:30:47.000000000 -0400
@@ -12039,9 +12039,11 @@ lpfc_sli4_fcf_scan_read_fcf_rec(struct l
phba->hba_flag |= FCF_DISC_INPROGRESS;
spin_unlock_irq(&phba->hbalock);
/* Reset FCF round robin index bmask for new scan */
- if (fcf_index == LPFC_FCOE_FCF_GET_FIRST)
+ if (fcf_index == LPFC_FCOE_FCF_GET_FIRST) {
memset(phba->fcf.fcf_rr_bmask, 0,
sizeof(*phba->fcf.fcf_rr_bmask));
+ phba->fcf.eligible_fcf_cnt = 0;
+ }
error = 0;
}
fail_fcf_scan:
--
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