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cyclic xcall: use smp_no_rendevous_barrier as setup function parameter

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In this case we call target function only on a single CPU and do not
need any synchronization at the setup stage.

It's a bit non-obvious but setup function of NULL means that
smp_rendezvous_cpus waits for all CPUs to arrive at the rendezvous
point, but without doing any actual setup.  While using
smp_no_rendevous_barrier means that each CPU proceeds on its own
schedule without any synchronization whatsoever.

MFC after:	3 weeks
This commit is contained in:
avg 2010-12-17 18:22:50 +00:00
parent 1b88c87408
commit 34b3952bdd
1 changed files with 2 additions and 2 deletions
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4
sys/cddl/dev/cyclic/i386/cyclic_machdep.c
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@ -122,6 +122,6 @@ static void reprogram(cyb_arg_t arg, hrtime_t exp)
static void xcall(cyb_arg_t arg, cpu_t *c, cyc_func_t func, void *param)
{
smp_rendezvous_cpus((cpumask_t) (1 << c->cpuid), NULL,
func, smp_no_rendevous_barrier, param);
smp_rendezvous_cpus((cpumask_t) (1 << c->cpuid),
smp_no_rendevous_barrier, func, smp_no_rendevous_barrier, param);
}