Re: [REQUEST DISCUSS]: speed up SCSI error handle for host with massive devices

From: Hannes Reinecke
Date: Mon Apr 04 2022 - 01:28:09 EST


On 4/3/22 19:17, Mike Christie wrote:
On 4/3/22 12:14 PM, Mike Christie wrote:
We could share code with scsi_ioctl_reset as well. Drivers that support
TMFs via that ioctl already expect queuecommand to be possibly in the
middle of a run and IO not yet timed out. For example, the code to
block a queue and reset the device could be used for the new EH and
SG_SCSI_RESET_DEVICE handling.


Hannes or others,

How do parallel SCSI drivers support scsi_ioctl_reset? Is is not fully
supported and more only used for controlled testing?

That's actually a problem in scsi_ioctl_reset(); it really should wait for all I/O to quiesce. Currently it just sets the 'tmf' flag and calls into the various reset functions.

But really, I'd rather get my EH rework in before we're start discussing modifying EH behaviour.
Let me repost it ...

Cheers,

Hannes
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Dr. Hannes Reinecke Kernel Storage Architect
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