[PATCH 3.16 027/133] scsi: zfcp: fix missing trace records for early returns in TMF eh handlers

From: Ben Hutchings
Date: Tue Nov 21 2017 - 21:45:39 EST


3.16.51-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Steffen Maier <maier@xxxxxxxxxxxxxxxxxx>

commit 1a5d999ebfc7bfe28deb48931bb57faa8e4102b6 upstream.

For problem determination we need to see that we were in scsi_eh
as well as whether and why we were successful or not.

The following commits introduced new early returns without adding
a trace record:

v2.6.35 commit a1dbfddd02d2
("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to scsi eh")
on fc_block_scsi_eh() returning != 0 which is FAST_IO_FAIL,

v2.6.30 commit 63caf367e1c9
("[SCSI] zfcp: Improve reliability of SCSI eh handlers in zfcp")
on not having gotten an FSF request after the maximum number of retry
attempts and thus could not issue a TMF and has to return FAILED.

Signed-off-by: Steffen Maier <maier@xxxxxxxxxxxxxxxxxx>
Fixes: a1dbfddd02d2 ("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to scsi eh")
Fixes: 63caf367e1c9 ("[SCSI] zfcp: Improve reliability of SCSI eh handlers in zfcp")
Reviewed-by: Benjamin Block <bblock@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Benjamin Block <bblock@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/s390/scsi/zfcp_scsi.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

--- a/drivers/s390/scsi/zfcp_scsi.c
+++ b/drivers/s390/scsi/zfcp_scsi.c
@@ -294,8 +294,10 @@ static int zfcp_task_mgmt_function(struc

zfcp_erp_wait(adapter);
ret = fc_block_scsi_eh(scpnt);
- if (ret)
+ if (ret) {
+ zfcp_dbf_scsi_devreset("fiof", scpnt, tm_flags, NULL);
return ret;
+ }

if (!(atomic_read(&adapter->status) &
ZFCP_STATUS_COMMON_RUNNING)) {
@@ -303,8 +305,10 @@ static int zfcp_task_mgmt_function(struc
return SUCCESS;
}
}
- if (!fsf_req)
+ if (!fsf_req) {
+ zfcp_dbf_scsi_devreset("reqf", scpnt, tm_flags, NULL);
return FAILED;
+ }

wait_for_completion(&fsf_req->completion);