scsi: core: avoid repetitive logging of device offline messages

Large queues of I/O to offline devices that are eventually submitted when
devices are unblocked result in a many repeated "rejecting I/O to offline
device" messages.  These messages can fill up the dmesg buffer in crash
dumps so no useful prior messages remain.  In addition, if a serial console
is used, the flood of messages can cause a hard lockup in the console code.

Introduce a flag indicating the message has already been logged for the
device, and reset the flag when scsi_device_set_state() changes the device
state.

Link: https://lore.kernel.org/r/20200311143930.20674-1-emilne@redhat.com
Reviewed-by: Bart van Assche <bvanassche@acm.org>
Signed-off-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Ewan D. Milne 2020-03-11 10:39:30 -04:00 committed by Martin K. Petersen
parent dade67f4a5
commit b0962c53bd
2 changed files with 9 additions and 2 deletions

View File

@ -1215,8 +1215,11 @@ scsi_prep_state_check(struct scsi_device *sdev, struct request *req)
* commands. The device must be brought online
* before trying any recovery commands.
*/
sdev_printk(KERN_ERR, sdev,
"rejecting I/O to offline device\n");
if (!sdev->offline_already) {
sdev->offline_already = true;
sdev_printk(KERN_ERR, sdev,
"rejecting I/O to offline device\n");
}
return BLK_STS_IOERR;
case SDEV_DEL:
/*
@ -2326,6 +2329,7 @@ scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state)
break;
}
sdev->offline_already = false;
sdev->sdev_state = state;
return 0;

View File

@ -203,6 +203,9 @@ struct scsi_device {
unsigned unmap_limit_for_ws:1; /* Use the UNMAP limit for WRITE SAME */
unsigned rpm_autosuspend:1; /* Enable runtime autosuspend at device
* creation time */
bool offline_already; /* Device offline message logged */
atomic_t disk_events_disable_depth; /* disable depth for disk events */
DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */