Re: [PATCH v5 16/16] nvme: Add support for CQT to nvme host

[Hannes Reinecke]

On 7/12/26 4:23 AM, Mohamed Khalfella wrote:
> TP4129 KATO Corrections and Clarifications defined CQT (Command Quiesce
> Time) which is used along with KATO (Keep Alive Timeout) to set an upper
> limit for attempting Cross-Controller Recovery. Add ctrl->cqt, read its
> value from controller identify response, expose it via sysfs, and have
> nvme_fence_timeout_ms() account for it.
>
> Use CQT to drive time-based recovery in fc, rdma, and tcp transports.
> Add a fenced_work delayed work to each transport controller. If CCR
> fails, fencing_work switches to error recovery immediately if CQT is not
> supported. Otherwise it schedules fenced_work after the remaining fence
> timeout, which also switches to error recovery when scheduled.
>
> Signed-off-by: Mohamed Khalfella <mkhalfella@xxxxxxxxxxxxxxx>
> ---
>   drivers/nvme/host/core.c  |  1 +
>   drivers/nvme/host/fc.c    | 41 +++++++++++++++++++++++++++++++++++----
>   drivers/nvme/host/nvme.h  |  5 +++--
>   drivers/nvme/host/rdma.c  | 41 +++++++++++++++++++++++++++++++++++----
>   drivers/nvme/host/sysfs.c |  2 ++
>   drivers/nvme/host/tcp.c   | 41 +++++++++++++++++++++++++++++++++++----
>   6 files changed, 117 insertions(+), 14 deletions(-)
Reviewed-by: Hannes Reinecke <hare@xxxxxxxxxx>

Cheers,

Hannes
--
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@xxxxxxx                                +49 911 74053 688
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