2021-01-07 11:46:10

by Li Jinlin

Subject: scsi: Add diagnostic log for scsi device reset

From: lijinlin <[email protected]>

For enhancing diagnosis capability when scsi device reset??we direct print
these logs which are infrequently printed, and add disk name to logs.

logs as follow:
[ 550.268049] sd 3:0:0:0: [sdc] Sending device reset
[ 550.268053] sd 3:0:0:0: [sdc] Sending target reset
[ 550.268055] sd 3:0:0:0: [sdc] Sending bus reset
[ 550.268056] sd 3:0:0:0: [sdc] Sending host reset

Signed-off-by: lijinlin <[email protected]>
---
drivers/scsi/scsi_error.c | 31 ++++++++++++++++---------------
1 file changed, 16 insertions(+), 15 deletions(-)

diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index f11f51e..3e62ade 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -1507,9 +1507,10 @@ static int scsi_eh_bus_device_reset(struct Scsi_Host *shost,
if (!bdr_scmd)
continue;

- SCSI_LOG_ERROR_RECOVERY(3,
+ if (bdr_scmd->request && bdr_scmd->request->rq_disk)
sdev_printk(KERN_INFO, sdev,
- "%s: Sending BDR\n", current->comm));
+ "[%s] Sending device reset\n",
+ bdr_scmd->request->rq_disk->disk_name);
rtn = scsi_try_bus_device_reset(bdr_scmd);
if (rtn == SUCCESS || rtn == FAST_IO_FAIL) {
if (!scsi_device_online(sdev) ||
@@ -1570,10 +1571,10 @@ static int scsi_eh_target_reset(struct Scsi_Host *shost,
scmd = list_entry(tmp_list.next, struct scsi_cmnd, eh_entry);
id = scmd_id(scmd);

- SCSI_LOG_ERROR_RECOVERY(3,
- shost_printk(KERN_INFO, shost,
- "%s: Sending target reset to target %d\n",
- current->comm, id));
+ if (scmd->device && scmd->request && scmd->request->rq_disk)
+ sdev_printk(KERN_INFO, scmd->device,
+ "[%s] Sending target reset\n",
+ scmd->request->rq_disk->disk_name);
rtn = scsi_try_target_reset(scmd);
if (rtn != SUCCESS && rtn != FAST_IO_FAIL)
SCSI_LOG_ERROR_RECOVERY(3,
@@ -1644,10 +1645,11 @@ static int scsi_eh_bus_reset(struct Scsi_Host *shost,

if (!chan_scmd)
continue;
- SCSI_LOG_ERROR_RECOVERY(3,
- shost_printk(KERN_INFO, shost,
- "%s: Sending BRST chan: %d\n",
- current->comm, channel));
+ if (chan_scmd->device && chan_scmd->request
+ && chan_scmd->request->rq_disk)
+ sdev_printk(KERN_INFO, chan_scmd->device,
+ "[%s] Sending bus reset\n",
+ chan_scmd->request->rq_disk->disk_name);
rtn = scsi_try_bus_reset(chan_scmd);
if (rtn == SUCCESS || rtn == FAST_IO_FAIL) {
list_for_each_entry_safe(scmd, next, work_q, eh_entry) {
@@ -1688,11 +1690,10 @@ static int scsi_eh_host_reset(struct Scsi_Host *shost,
scmd = list_entry(work_q->next,
struct scsi_cmnd, eh_entry);

- SCSI_LOG_ERROR_RECOVERY(3,
- shost_printk(KERN_INFO, shost,
- "%s: Sending HRST\n",
- current->comm));
-
+ if (scmd->device && scmd->request && scmd->request->rq_disk)
+ sdev_printk(KERN_INFO, scmd->device,
+ "[%s] Sending host reset\n",
+ scmd->request->rq_disk->disk_name);
rtn = scsi_try_host_reset(scmd);
if (rtn == SUCCESS) {
list_splice_init(work_q, &check_list);
--
1.8.3.1

2021-01-07 16:51:11

by James Bottomley

Subject: Re: scsi: Add diagnostic log for scsi device reset

On Thu, 2021-01-07 at 19:43 +0800, lijinlin wrote:
[...]
> - SCSI_LOG_ERROR_RECOVERY(3,
> + if (bdr_scmd->request && bdr_scmd->request->rq_disk)
> sdev_printk(KERN_INFO, sdev,
> - "%s: Sending BDR\n", current-
> >comm));
> + "[%s] Sending device reset\n",
> + bdr_scmd->request->rq_disk-
> >disk_name);

Not everything is a SCSI disk. If we apply this patch, we lose traces
for any non-disk device that get reset ... for tapes this can be really
important to know.

James