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Remove bogus need_resched() of the current CPU in roundrobin().

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We don't actually need to force a context switch of the current process.
The act of firing the event triggers a context switch to softclock() and
then switching back out again which is equivalent to a preemption, thus
no further work is needed on the local CPU.
This commit is contained in:
jhb 2001-07-03 05:33:09 +00:00
parent 7bb1f29898
commit 774b040e8a
1 changed files with 6 additions and 3 deletions
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9
sys/kern/kern_synch.c
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@ -120,6 +120,10 @@ roundrobin_interval(void)
/*
* Force switch among equal priority processes every 100ms.
* We don't actually need to force a context switch of the current process.
* The act of firing the event triggers a context switch to softclock() and
* then switching back out again which is equivalent to a preemption, thus
* no further work is needed on the local CPU.
*/
/* ARGSUSED */
static void
@ -127,12 +131,11 @@ roundrobin(arg)
void *arg;
{
mtx_lock_spin(&sched_lock);
need_resched(curproc);
#ifdef SMP
mtx_lock_spin(&sched_lock);
forward_roundrobin();
#endif
mtx_unlock_spin(&sched_lock);
#endif
callout_reset(&roundrobin_callout, sched_quantum, roundrobin, NULL);
}