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SMP - Balancing run queues for SMP

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- it preempts running processes though :( this is not the final
  solution
This commit is contained in:
Tomas Hruby 2010-09-15 14:10:51 +00:00
parent 06b6e5624a
commit 311f145bc7
2 changed files with 53 additions and 17 deletions
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13
kernel/system.c
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@ -662,11 +662,14 @@ PUBLIC int sched_proc(struct proc *p,
/* FIXME this is a problem for SMP if the processes currently runs on a
* different CPU */
if (proc_is_runnable(p) && p->p_cpu != cpuid &&
(cpu != -1 || cpu != p->p_cpu)) {
printf("WARNING : changing cpu of a runnable process %d "
"on a different cpu!\n", p->p_endpoint);
return(EINVAL);
if (proc_is_runnable(p)) {
if (p->p_cpu != cpuid && cpu != -1 && cpu != p->p_cpu) {
printf("WARNING : changing cpu of a runnable process %d "
"on a different cpu!\n", p->p_endpoint);
return(EINVAL);
}
RTS_SET(p, RTS_NO_QUANTUM);
}
if (proc_is_runnable(p))

57
servers/sched/schedule.c
View file

@ -19,9 +19,25 @@ PRIVATE unsigned balance_timeout;
#define BALANCE_TIMEOUT 5 /* how often to balance queues in seconds */
FORWARD _PROTOTYPE( int schedule_process, (struct schedproc * rmp) );
FORWARD _PROTOTYPE( int schedule_process, (struct schedproc * rmp,
unsigned flags));
FORWARD _PROTOTYPE( void balance_queues, (struct timer *tp) );
#define SCHEDULE_CHANGE_PRIO 0x1
#define SCHEDULE_CHANGE_QUANTUM 0x2
#define SCHEDULE_CHANGE_CPU 0x4
#define SCHEDULE_CHANGE_ALL ( \
SCHEDULE_CHANGE_PRIO | \
SCHEDULE_CHANGE_QUANTUM | \
SCHEDULE_CHANGE_CPU \
)
#define schedule_process_local(p) \
schedule_process(p, SCHEDULE_CHANGE_PRIO | SCHEDULE_CHANGE_QUANTUM)
#define schedule_process_migrate(p) \
schedule_process(p, SCHEDULE_CHANGE_CPU)
#define DEFAULT_USER_TIME_SLICE 200
/* processes created by RS are sysytem processes */
@ -79,7 +95,7 @@ PUBLIC int do_noquantum(message *m_ptr)
rmp->priority += 1; /* lower priority */
}
if ((rv = schedule_process(rmp)) != OK) {
if ((rv = schedule_process_local(rmp)) != OK) {
return rv;
}
return OK;
@ -197,7 +213,8 @@ PUBLIC int do_start_scheduling(message *m_ptr)
rmp->flags = IN_USE;
/* Schedule the process, giving it some quantum */
if ((rv = schedule_process(rmp)) != OK) {
pick_cpu(rmp);
if ((rv = schedule_process(rmp, SCHEDULE_CHANGE_ALL)) != OK) {
printf("Sched: Error while scheduling process, kernel replied %d\n",
rv);
return rv;
@ -248,7 +265,7 @@ PUBLIC int do_nice(message *m_ptr)
/* Update the proc entry and reschedule the process */
rmp->max_priority = rmp->priority = new_q;
if ((rv = schedule_process(rmp)) != OK) {
if ((rv = schedule_process_local(rmp)) != OK) {
/* Something went wrong when rescheduling the process, roll
* back the changes to proc struct */
rmp->priority = old_q;
@ -261,19 +278,35 @@ PUBLIC int do_nice(message *m_ptr)
/*===========================================================================*
* schedule_process *
*===========================================================================*/
PRIVATE int schedule_process(struct schedproc * rmp)
PRIVATE int schedule_process(struct schedproc * rmp, unsigned flags)
{
int rv;
int err;
int new_prio, new_quantum, new_cpu;
pick_cpu(rmp);
if ((rv = sys_schedule(rmp->endpoint, rmp->priority,
rmp->time_slice, rmp->cpu)) != OK) {
printf("SCHED: An error occurred when trying to schedule %d: %d\n",
rmp->endpoint, rv);
if (flags & SCHEDULE_CHANGE_PRIO)
new_prio = rmp->priority;
else
new_prio = -1;
if (flags & SCHEDULE_CHANGE_QUANTUM)
new_quantum = rmp->time_slice;
else
new_quantum = -1;
if (flags & SCHEDULE_CHANGE_CPU)
new_cpu = rmp->cpu;
else
new_cpu = -1;
if ((err = sys_schedule(rmp->endpoint, new_prio,
new_quantum, new_cpu)) != OK) {
printf("PM: An error occurred when trying to schedule %d: %d\n",
rmp->endpoint, err);
}
return rv;
return err;
}
@ -307,7 +340,7 @@ PRIVATE void balance_queues(struct timer *tp)
if (rmp->flags & IN_USE) {
if (rmp->priority > rmp->max_priority) {
rmp->priority -= 1; /* increase priority */
schedule_process(rmp);
schedule_process_local(rmp);
}
}
}