[PATCH v1 0/3] Asynchronous shutdown interface and example implementation

[Greg Kroah-Hartman]

On Mon, Mar 28, 2022 at 04:00:05PM -0700, Tanjore Suresh wrote:
> Problem:
> 
> Some of our machines are configured with  many NVMe devices and
> are validated for strict shutdown time requirements. Each NVMe
> device plugged into the system, typicaly takes about 4.5 secs
> to shutdown. A system with 16 such NVMe devices will takes
> approximately 80 secs to shutdown and go through reboot.
> 
> The current shutdown APIs as defined at bus level is defined to be
> synchronous. Therefore, more devices are in the system the greater
> the time it takes to shutdown. This shutdown time significantly
> contributes the machine reboot time.
> 
> Solution:
> 
> This patch set proposes an asynchronous shutdown interface at bus level,
> modifies the core driver, device shutdown routine to exploit the
> new interface while maintaining backward compatibility with synchronous
> implementation already existing (Patch 1 of 3) and exploits new interface
> to enable all PCI-E based devices to use asynchronous interface semantics
> if necessary (Patch 2 of 3). The implementation at PCI-E level also works
> in a backward compatible way, to allow exiting device implementation
> to work with current synchronous semantics. Only show cases an example
> implementation for NVMe device to exploit this asynchronous shutdown
> interface. (Patch 3 of 3).
> 
> Tanjore Suresh (3):
>   driver core: Support asynchronous driver shutdown
>   PCI: Support asynchronous shutdown
>   nvme: Add async shutdown support
> 
>  drivers/base/core.c        | 39 ++++++++++++++++++-
>  drivers/nvme/host/core.c   | 28 +++++++++----
>  drivers/nvme/host/nvme.h   |  8 ++++
>  drivers/nvme/host/pci.c    | 80 ++++++++++++++++++++++++--------------
>  drivers/pci/pci-driver.c   | 17 ++++++--
>  include/linux/device/bus.h | 10 +++++
>  include/linux/pci.h        |  2 +
>  7 files changed, 144 insertions(+), 40 deletions(-)
> 
> -- 
> 2.35.1.1021.g381101b075-goog
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
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created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

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