| Message ID | 20200311143930.20674-1-emilne@redhat.com (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | b0962c53bde9a485c8ebc401fa1dbe821a76bc3e |
| Headers | show |
| Series | [v2] scsi: avoid repetitive logging of device offline messages | expand |
On 2020-03-11 07:39, Ewan D. Milne wrote: > 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. > > v2: > Changed flag type from bitfield to bool by request Thanks! Reviewed-by: Bart van Assche <bvanassche@acm.org>
Ewan, > 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. Applied to 5.7/scsi-queue, thanks!
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 610ee41..a45e728 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -1240,8 +1240,11 @@ 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: /* @@ -2340,6 +2343,7 @@ scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state) break; } + sdev->offline_already = false; sdev->sdev_state = state; return 0; diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index f8312a3..cd9656f 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -204,6 +204,9 @@ 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 */
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. v2: Changed flag type from bitfield to bool by request Signed-off-by: Ewan D. Milne <emilne@redhat.com> --- drivers/scsi/scsi_lib.c | 8 ++++++-- include/scsi/scsi_device.h | 3 +++ 2 files changed, 9 insertions(+), 2 deletions(-)