d/freebsd-nq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

- Minimize the amount of duplicated code for the PREEMPTION #ifdef, it now

Browse Source 
only covers about 3-4 lines.
- Don't lower the IPL while we are on the interrupt stack.  Instead, save
  the raised IPL and change the saved IPL in sched_lock to IPL_0 before
  calling mi_switch().  When we are resumed, restore the saved IPL in
  sched_lock to the saved raised IPL so that when we release sched_lock
  we won't lower the IPL.  Without this, we would get nested interrupts
  that would overflow the kernel stack.

Tested by:	mjacob
This commit is contained in:
John Baldwin 2001-02-05 19:34:25 +00:00
parent 9d72a7a3f8
commit f933f02094
1 changed files with 9 additions and 27 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

36
sys/alpha/alpha/interrupt.c
View File

@ -504,6 +504,7 @@ alpha_dispatch_intr(void *frame, unsigned long vector)
int h = HASHVEC(vector);
struct alpha_intr *i;
struct ithd *ithd; /* our interrupt thread */
int saveintr;
/*
* Walk the hash bucket for this vector looking for this vector's
@ -554,14 +555,11 @@ alpha_dispatch_intr(void *frame, unsigned long vector)
* is higher priority than their current thread, it gets run now.
*/
ithd->it_need = 1;
#ifdef PREEMPTION
/* Does not work on 4100 and PC164 */
if (i->disable) {
CTR1(KTR_INTR,
"alpha_dispatch_intr: disabling vector 0x%x", i->vector);
i->disable(i->vector);
}
enable_intr();
mtx_enter(&sched_lock, MTX_SPIN);
if (ithd->it_proc->p_stat == SWAIT) {
/* not on the run queue and not running */
@ -571,41 +569,25 @@ alpha_dispatch_intr(void *frame, unsigned long vector)
alpha_mb(); /* XXX - ??? */
ithd->it_proc->p_stat = SRUN;
setrunqueue(ithd->it_proc);
#ifdef PREEMPTION
/* Does not work on 4100 and PC164 */
if (!cold) {
saveintr = sched_lock.mtx_saveintr;
sched_lock.mtx_saveintr = ALPHA_PSL_IPL_0;
if (curproc != PCPU_GET(idleproc))
setrunqueue(curproc);
mi_switch();
sched_lock.mtx_saveintr = saveintr;
}
#else
need_resched();
#endif
} else {
CTR3(KTR_INTR, "alpha_dispatch_intr: %d: it_need %d, state %d",
ithd->it_proc->p_pid, ithd->it_need, ithd->it_proc->p_stat);
need_resched();
}
mtx_exit(&sched_lock, MTX_SPIN);
#else
mtx_enter(&sched_lock, MTX_SPIN);
if (ithd->it_proc->p_stat == SWAIT) {
/* not on the run queue and not running */
CTR1(KTR_INTR, "alpha_dispatch_intr: setrunqueue %d",
ithd->it_proc->p_pid);
alpha_mb(); /* XXX - ??? */
ithd->it_proc->p_stat = SRUN;
setrunqueue(ithd->it_proc);
aston();
} else {
CTR3(KTR_INTR, "alpha_dispatch_intr: %d: it_need %d, state %d",
ithd->it_proc->p_pid, ithd->it_need, ithd->it_proc->p_stat);
}
if (i->disable) {
CTR1(KTR_INTR,
"alpha_dispatch_intr: disabling vector 0x%x", i->vector);
i->disable(i->vector);
}
mtx_exit(&sched_lock, MTX_SPIN);
need_resched();
#endif
}
void