[SCSI] fcoe: removes fcoe_watchdog
Removes periodic fcoe_watchdog timer used across all fcoe interface
maintained in fcoe_hostlist instead added new fcoe_queue_timer
per fcoe interface.
Added timer is armed only when some pending skb need to be flushed
as oppose to periodic 1 second fcoe_watchdog, since now
fcoe_queue_timer is used on demand thus set this to 2 jiffies.
Now fcoe_queue_timer is much simple than fcoe_watchdog using lock to
process all fcoe interface from fcoe_hostlist.
I noticed +ve performance result with using 2 jiffies timer as
this helps flushing fcoe_pending_queue quickly.
Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c
index 30eba75..6e7a700 100644
--- a/drivers/scsi/fcoe/fcoe.c
+++ b/drivers/scsi/fcoe/fcoe.c
@@ -54,7 +54,6 @@
/* fcoe host list */
LIST_HEAD(fcoe_hostlist);
DEFINE_RWLOCK(fcoe_hostlist_lock);
-DEFINE_TIMER(fcoe_timer, NULL, 0, 0);
DEFINE_PER_CPU(struct fcoe_percpu_s, fcoe_percpu);
/* Function Prototypes */
@@ -168,6 +167,18 @@
}
/**
+ * fcoe_queue_timer() - fcoe queue timer
+ * @lp: the fc_lport pointer
+ *
+ * Calls fcoe_check_wait_queue on timeout
+ *
+ */
+static void fcoe_queue_timer(ulong lp)
+{
+ fcoe_check_wait_queue((struct fc_lport *)lp, NULL);
+}
+
+/**
* fcoe_netdev_config() - Set up netdev for SW FCoE
* @lp : ptr to the fc_lport
* @netdev : ptr to the associated netdevice struct
@@ -237,6 +248,7 @@
}
skb_queue_head_init(&fc->fcoe_pending_queue);
fc->fcoe_pending_queue_active = 0;
+ setup_timer(&fc->timer, fcoe_queue_timer, (unsigned long)lp);
/* setup Source Mac Address */
memcpy(fc->ctlr.ctl_src_addr, fc->real_dev->dev_addr,
@@ -387,6 +399,9 @@
/* Free existing skbs */
fcoe_clean_pending_queue(lp);
+ /* Stop the timer */
+ del_timer_sync(&fc->timer);
+
/* Free memory used by statistical counters */
fc_lport_free_stats(lp);
@@ -1260,32 +1275,6 @@
}
/**
- * fcoe_watchdog() - fcoe timer callback
- * @vp:
- *
- * This checks the pending queue length for fcoe and set lport qfull
- * if the FCOE_MAX_QUEUE_DEPTH is reached. This is done for all fc_lport on the
- * fcoe_hostlist.
- *
- * Returns: 0 for success
- */
-void fcoe_watchdog(ulong vp)
-{
- struct fcoe_softc *fc;
-
- read_lock(&fcoe_hostlist_lock);
- list_for_each_entry(fc, &fcoe_hostlist, list) {
- if (fc->ctlr.lp)
- fcoe_check_wait_queue(fc->ctlr.lp, NULL);
- }
- read_unlock(&fcoe_hostlist_lock);
-
- fcoe_timer.expires = jiffies + (1 * HZ);
- add_timer(&fcoe_timer);
-}
-
-
-/**
* fcoe_check_wait_queue() - attempt to clear the transmit backlog
* @lp: the fc_lport
*
@@ -1333,6 +1322,8 @@
if (fc->fcoe_pending_queue.qlen < FCOE_LOW_QUEUE_DEPTH)
lp->qfull = 0;
+ if (fc->fcoe_pending_queue.qlen && !timer_pending(&fc->timer))
+ mod_timer(&fc->timer, jiffies + 2);
fc->fcoe_pending_queue_active = 0;
out:
if (fc->fcoe_pending_queue.qlen > FCOE_MAX_QUEUE_DEPTH)
@@ -1809,10 +1800,6 @@
/* Setup link change notification */
fcoe_dev_setup();
- setup_timer(&fcoe_timer, fcoe_watchdog, 0);
-
- mod_timer(&fcoe_timer, jiffies + (10 * HZ));
-
fcoe_if_init();
return 0;
@@ -1838,9 +1825,6 @@
fcoe_dev_cleanup();
- /* Stop the timer */
- del_timer_sync(&fcoe_timer);
-
/* releases the associated fcoe hosts */
list_for_each_entry_safe(fc, tmp, &fcoe_hostlist, list)
fcoe_if_destroy(fc->real_dev);