usleep_range(9) [centos man page]

USLEEP_RANGE(9) 						   Driver Basics						   USLEEP_RANGE(9)

NAME

       usleep_range - Drop in replacement for udelay where wakeup is flexible

SYNOPSIS

       void usleep_range(unsigned long min, unsigned long max);

ARGUMENTS

       min
	   Minimum time in usecs to sleep

       max
	   Maximum time in usecs to sleep

COPYRIGHT

Kernel Hackers Manual 3.10					     June 2014							   USLEEP_RANGE(9)

SCHEDULE_HRTIMEOUT_R(9) 					   Driver Basics					   SCHEDULE_HRTIMEOUT_R(9)

NAME

       schedule_hrtimeout_range - sleep until timeout

SYNOPSIS

       int __sched schedule_hrtimeout_range(ktime_t * expires, unsigned long delta, const enum hrtimer_mode mode);

ARGUMENTS

       expires
	   timeout value (ktime_t)

       delta
	   slack in expires timeout (ktime_t)

       mode
	   timer mode, HRTIMER_MODE_ABS or HRTIMER_MODE_REL

DESCRIPTION

       Make the current task sleep until the given expiry time has elapsed. The routine will return immediately unless the current task state has
       been set (see set_current_state).

       The delta argument gives the kernel the freedom to schedule the actual wakeup to a time that is both power and performance friendly. The
       kernel give the normal best effort behavior for "expires+delta", but may decide to fire the timer earlier, but no earlier than expires.

       You can set the task state as follows -

       TASK_UNINTERRUPTIBLE - at least timeout time is guaranteed to pass before the routine returns.

       TASK_INTERRUPTIBLE - the routine may return early if a signal is delivered to the current task.

       The current task state is guaranteed to be TASK_RUNNING when this routine returns.

       Returns 0 when the timer has expired otherwise -EINTR

COPYRIGHT

Kernel Hackers Manual 3.10					     June 2014						   SCHEDULE_HRTIMEOUT_R(9)