Kernel utility functions

upper_32_bits — return bits 32-63 of a number
lower_32_bits — return bits 0-31 of a number
might_sleep — annotation for functions that can sleep
trace_printk — printf formatting in the ftrace buffer
min_not_zero — return the minimum that is _not_ zero, unless both are zero
clamp — return a value clamped to a given range with strict typechecking
clamp_t — return a value clamped to a given range using a given type
clamp_val — return a value clamped to a given range using val's type
container_of — cast a member of a structure out to the containing structure
BUILD_BUG_ON — break compile if a condition is true.
printk — print a kernel message
console_lock — lock the console system for exclusive use.
console_trylock — try to lock the console system for exclusive use.
console_unlock — unlock the console system
console_conditional_schedule — yield the CPU if required
printk_timed_ratelimit — caller-controlled printk ratelimiting
kmsg_dump_register — register a kernel log dumper.
kmsg_dump_unregister — unregister a kmsg dumper.
panic — halt the system
emergency_restart — reboot the system
kernel_restart — reboot the system
kernel_halt — halt the system
kernel_power_off — power_off the system
orderly_poweroff — Trigger an orderly system poweroff
rcu_read_lock_bh_held — might we be in RCU-bh read-side critical section?
init_rcu_head_on_stack — initialize on-stack rcu_head for debugobjects
destroy_rcu_head_on_stack — destroy on-stack rcu_head for debugobjects