SYNCHRONIZE_SCHED(9) Driver Basics SYNCHRONIZE_SCHED(9)NAMEsynchronize_sched - wait until an rcu-sched grace period has elapsed.
SYNOPSIS
void synchronize_sched(void);
ARGUMENTS
void
no arguments
DESCRIPTION
Control will return to the caller some time after a full rcu-sched
grace period has elapsed, in other words after all currently executing
rcu-sched read-side critical sections have completed. These read-side
critical sections are delimited by rcu_read_lock_sched and
rcu_read_unlock_sched, and may be nested. Note that preempt_disable,
local_irq_disable, and so on may be used in place of
rcu_read_lock_sched.
This means that all preempt_disable code sequences, including NMI and
hardware-interrupt handlers, in progress on entry will have completed
before this primitive returns. However, this does not guarantee that
softirq handlers will have completed, since in some kernels, these
handlers can run in process context, and can block.
This primitive provides the guarantees made by the (now removed)
synchronize_kernel API. In contrast, synchronize_rcu only guarantees
that rcu_read_lock sections will have completed. In “classic RCU”,
these two guarantees happen to be one and the same, but can differ in
realtime RCU implementations.
COPYRIGHTKernel Hackers Manual 2.6. November 2013 SYNCHRONIZE_SCHED(9)