Kernel utility functions

upper_32_bits — return bits 32-63 of a number
container_of — cast a member of a structure out to the containing structure
printk — print a kernel message
acquire_console_sem — lock the console system for exclusive use.
release_console_sem — unlock the console system
console_conditional_schedule — yield the CPU if required
printk_timed_ratelimit — caller-controlled printk ratelimiting
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
call_rcu — Queue an RCU callback for invocation after a grace period.
call_rcu_bh — Queue an RCU for invocation after a quicker grace period.
rcu_barrier — Wait until all the in-flight RCUs are complete.
synchronize_rcu — wait until a grace period has elapsed.