diff options
author | Christof Schmitt <christof.schmitt@de.ibm.com> | 2009-07-13 15:06:10 +0200 |
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committer | James Bottomley <James.Bottomley@HansenPartnership.com> | 2009-07-30 08:49:57 -0500 |
commit | cbf1ed0264da104573458aedc220ebfcd02567f6 (patch) | |
tree | e3a8e5f815fd22c556a61189c0d3e0d0658fa87d /drivers/s390/scsi/zfcp_dbf.h | |
parent | 85600f7f8370fe5b4be0debd8b401de7986b52ae (diff) |
[SCSI] zfcp: Recover from stalled outbound queue
Depending on interruptions on some storage systems, the complete
channel can stall which looks like an outbound queue stall to Linux.
When trying to acquire a free SBAL for a non-SCSI command, zfcp waits
for 5 seconds for a free slot to appear. This is the right place to
detect a queue stall: If the wait times out, we assume a stalled queue
and try to recover this.
The overall strategy should be to trigger the erp from specific
events, and not try an overall escalation from one failed port to a
full-blown queue recovery. If we manage to send a command, the status
codes for this command or a timeout will trigger the right follow-on
actions.
Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Diffstat (limited to 'drivers/s390/scsi/zfcp_dbf.h')
0 files changed, 0 insertions, 0 deletions