Re: [PATCH v2 0/2] usb: core: Improve device lifecycle debuggability

[Alan Stern]

On Wed, Oct 15, 2025 at 03:50:50AM +0800, Kuen-Han Tsai wrote:
> This series enhances USB core debuggability. The first patch refactors
> device state updates into a new update_usb_device_state() helper 
> function, centralizing logic and preparing for tracing.
> 
> The second patch adds tracepoints for USB device allocation and state 
> changes, providing better visibility into the device lifecycle.
> 
> Signed-off-by: Kuen-Han Tsai <khtsai@xxxxxxxxxx>
> ---

For both patches:

Reviewed-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>


> Changes in v2:
> - hub.c: Changed the inline function to a standard one.
> - Makefile: Moved trace.o to the preceding line.
> - trace.h: Changed the speed and state into strings.
> - Link to v1: https://lore.kernel.org/r/20251013-usbcore-tracing-v1-0-b885a3121b09@xxxxxxxxxx
> 
> ---
> Kuen-Han Tsai (2):
>       usb: core: Centralize device state update logic
>       usb: core: Add tracepoints for device allocation and state changes
> 
>  drivers/usb/core/Makefile |  5 +++-
>  drivers/usb/core/hub.c    | 30 +++++++++++++----------
>  drivers/usb/core/trace.c  |  6 +++++
>  drivers/usb/core/trace.h  | 61 +++++++++++++++++++++++++++++++++++++++++++++++
>  drivers/usb/core/usb.c    |  2 ++
>  5 files changed, 91 insertions(+), 13 deletions(-)
> ---
> base-commit: 5472d60c129f75282d94ae5ad072ee6dfb7c7246
> change-id: 20251012-usbcore-tracing-76f00c9b2b3e
> 
> Best regards,
> -- 
> Kuen-Han Tsai <khtsai@xxxxxxxxxx>
>