From c826a3145736e3baabebccfd0aecfbb6dae059f2 Mon Sep 17 00:00:00 2001 From: Vasu Dev Date: Fri, 27 Feb 2009 10:56:27 -0800 Subject: [SCSI] fcoe: Out of order tx frames was causing several check condition SCSI status frames followed by these errors in log. [sdp] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE,SUGGEST_OK [sdp] Sense Key : Aborted Command [current] [sdp] Add. Sense: Data phase error This was causing some test apps to exit due to write failure under heavy load. This was due to a race around adding and removing tx frame skb in fcoe_pending_queue, Chris Leech helped me to find that brief unlocking period when pulling skb from fcoe_pending_queue in various contexts (fcoe_watchdog and fcoe_xmit) and then adding skb back into fcoe_pending_queue up on a failed fcoe_start_io could change skb/tx frame order in fcoe_pending_queue. Thanks Chris. This patch allows only single context to pull skb from fcoe_pending_queue at any time to prevent above described ordering issue/race by use of fcoe_pending_queue_active flag. This patch simplified fcoe_watchdog with modified fcoe_check_wait_queue by use of FCOE_LOW_QUEUE_DEPTH instead previously used several conditionals to clear and set lp->qfull. I think FCOE_MAX_QUEUE_DEPTH with FCOE_LOW_QUEUE_DEPTH will work better in re/setting lp->qfull and these could be fine tuned for performance. Signed-off-by: Vasu Dev Signed-off-by: Robert Love Signed-off-by: James Bottomley --- include/scsi/libfcoe.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/scsi/libfcoe.h b/include/scsi/libfcoe.h index f43d3833a7a..941818f29f5 100644 --- a/include/scsi/libfcoe.h +++ b/include/scsi/libfcoe.h @@ -46,6 +46,7 @@ struct fcoe_softc { struct net_device *phys_dev; /* device with ethtool_ops */ struct packet_type fcoe_packet_type; struct sk_buff_head fcoe_pending_queue; + u8 fcoe_pending_queue_active; u8 dest_addr[ETH_ALEN]; u8 ctl_src_addr[ETH_ALEN]; -- cgit v1.2.3-18-g5258