diff options
| author | Kuen-Han Tsai <khtsai@google.com> | 2025-10-15 03:50:52 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-10-22 10:58:30 +0200 |
| commit | 071786e27d81d3e8ae11f078357c9373fc4ce2e8 (patch) | |
| tree | c6e682fb2d8098ddd53e8e85661469c1905338e6 /drivers/usb/core/usb.c | |
| parent | c05ebd0ec91e27408767c46dd16c291cbff2213d (diff) | |
usb: core: Add tracepoints for device allocation and state changes
Introduce new tracepoints to the USB core to improve debuggability of
USB device lifecycle events.
The following tracepoints are added:
- usb_alloc_dev: Triggered when a new USB device structure is allocated,
providing insights into early device setup.
- usb_set_device_state: Triggered when the USB device state changes,
allowing observation of the device's state transitions.
These tracepoints capture detailed information about the USB device,
including its name, speed, state, bus current value, and authorized
flag. This will aid developers in diagnosing issues related to device
enumeration within the USB subsystem.
Examples:
usb_alloc_dev: usb 1-1 speed UNKNOWN state attached 0mA [authorized]
usb_set_device_state: usb 1-1 speed UNKNOWN state powered 0mA [authorized]
usb_set_device_state: usb 1-1 speed full-speed state default 500mA [authorized]
usb_set_device_state: usb 1-1 speed full-speed state default 500mA [authorized]
usb_set_device_state: usb 1-1 speed full-speed state addressed 500mA [authorized]
usb_set_device_state: usb 1-1 speed full-speed state configured 500mA [authorized]
usb_set_device_state: usb 1-1 speed full-speed state suspended 500mA [authorized]
usb_set_device_state: usb 1-1 speed full-speed state not attached 500mA [authorized]
Signed-off-by: Kuen-Han Tsai <khtsai@google.com>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://patch.msgid.link/20251015-usbcore-tracing-v2-2-5a14b5b9d4e0@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/core/usb.c')
| -rw-r--r-- | drivers/usb/core/usb.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c index b6b0b8489523..e740f7852bcd 100644 --- a/drivers/usb/core/usb.c +++ b/drivers/usb/core/usb.c @@ -46,6 +46,7 @@ #include <linux/dma-mapping.h> #include "hub.h" +#include "trace.h" const char *usbcore_name = "usbcore"; @@ -746,6 +747,7 @@ struct usb_device *usb_alloc_dev(struct usb_device *parent, #endif dev->authorized = usb_dev_authorized(dev, usb_hcd); + trace_usb_alloc_dev(dev); return dev; } EXPORT_SYMBOL_GPL(usb_alloc_dev); |