scsi: hpsa: limit outstanding rescans
[ Upstream commit 87b9e6aa87d9411f1059aa245c0c79976bc557ac ]
Avoid rescan storms. No need to queue another if one is pending.
Reviewed-by: Scott Benesh <scott.benesh@microsemi.com>
Reviewed-by: Scott Teel <scott.teel@microsemi.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Don Brace <don.brace@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index 3c5a3fb..20e4278 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -5529,7 +5529,7 @@
spin_lock_irqsave(&h->scan_lock, flags);
h->scan_finished = 1;
- wake_up_all(&h->scan_wait_queue);
+ wake_up(&h->scan_wait_queue);
spin_unlock_irqrestore(&h->scan_lock, flags);
}
@@ -5547,11 +5547,23 @@
if (unlikely(lockup_detected(h)))
return hpsa_scan_complete(h);
+ /*
+ * If a scan is already waiting to run, no need to add another
+ */
+ spin_lock_irqsave(&h->scan_lock, flags);
+ if (h->scan_waiting) {
+ spin_unlock_irqrestore(&h->scan_lock, flags);
+ return;
+ }
+
+ spin_unlock_irqrestore(&h->scan_lock, flags);
+
/* wait until any scan already in progress is finished. */
while (1) {
spin_lock_irqsave(&h->scan_lock, flags);
if (h->scan_finished)
break;
+ h->scan_waiting = 1;
spin_unlock_irqrestore(&h->scan_lock, flags);
wait_event(h->scan_wait_queue, h->scan_finished);
/* Note: We don't need to worry about a race between this
@@ -5561,6 +5573,7 @@
*/
}
h->scan_finished = 0; /* mark scan as in progress */
+ h->scan_waiting = 0;
spin_unlock_irqrestore(&h->scan_lock, flags);
if (unlikely(lockup_detected(h)))
@@ -8799,6 +8812,7 @@
init_waitqueue_head(&h->event_sync_wait_queue);
mutex_init(&h->reset_mutex);
h->scan_finished = 1; /* no scan currently in progress */
+ h->scan_waiting = 0;
pci_set_drvdata(pdev, h);
h->ndevices = 0;
diff --git a/drivers/scsi/hpsa.h b/drivers/scsi/hpsa.h
index 9ea162d..e16f294 100644
--- a/drivers/scsi/hpsa.h
+++ b/drivers/scsi/hpsa.h
@@ -203,6 +203,7 @@
dma_addr_t errinfo_pool_dhandle;
unsigned long *cmd_pool_bits;
int scan_finished;
+ u8 scan_waiting : 1;
spinlock_t scan_lock;
wait_queue_head_t scan_wait_queue;