work_busy(9) [centos man page]

WORK_BUSY(9)							   Driver Basics						      WORK_BUSY(9)

NAME

       work_busy - test whether a work is currently pending or running

SYNOPSIS

       unsigned int work_busy(struct work_struct * work);

ARGUMENTS

       work
	   the work to be tested

DESCRIPTION

       Test whether work is currently pending or running. There is no synchronization around this function and the test result is unreliable and
       only useful as advisory hints or for debugging.

RETURNS

       OR'd bitmask of WORK_BUSY_* bits.

COPYRIGHT

Kernel Hackers Manual 3.10					     June 2014							      WORK_BUSY(9)

USB_QUEUE_RESET_DEVI(9) 					   USB Core APIs					   USB_QUEUE_RESET_DEVI(9)

NAME

       usb_queue_reset_device - Reset a USB device from an atomic context

SYNOPSIS

       void usb_queue_reset_device(struct usb_interface * iface);

ARGUMENTS

       iface
	   USB interface belonging to the device to reset

DESCRIPTION

       This function can be used to reset a USB device from an atomic context, where usb_reset_device won't work (as it blocks).

       Doing a reset via this method is functionally equivalent to calling usb_reset_device, except for the fact that it is delayed to a
       workqueue. This means that any drivers bound to other interfaces might be unbound, as well as users from usbfs in user space.

CORNER CASES

       - Scheduling two resets at the same time from two different drivers attached to two different interfaces of the same device is possible;
       depending on how the driver attached to each interface handles ->pre_reset, the second reset might happen or not.

       - If a driver is unbound and it had a pending reset, the reset will be cancelled.

       - This function can be called during .probe or .disconnect times. On return from .disconnect, any pending resets will be cancelled.

       There is no no need to lock/unlock the reset_ws as schedule_work does its own.

NOTE

       We don't do any reference count tracking because it is not needed. The lifecycle of the work_struct is tied to the usb_interface. Before
       destroying the interface we cancel the work_struct, so the fact that work_struct is queued and or running means the interface (and thus,
       the device) exist and are referenced.

COPYRIGHT

Kernel Hackers Manual 3.10					     June 2014						   USB_QUEUE_RESET_DEVI(9)