diff options
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/kern/kern_intr.c | 28 |
1 files changed, 23 insertions, 5 deletions
diff --git a/sys/kern/kern_intr.c b/sys/kern/kern_intr.c index 6569056..1156883 100644 --- a/sys/kern/kern_intr.c +++ b/sys/kern/kern_intr.c @@ -485,7 +485,7 @@ ithread_loop(void *arg) struct intrhand *ih; /* and our interrupt handler chain */ struct thread *td; struct proc *p; - int count, warned; + int count, warned, storming; td = curthread; p = td->td_proc; @@ -494,6 +494,7 @@ ithread_loop(void *arg) ("%s: ithread and proc linkage out of sync", __func__)); count = 0; warned = 0; + storming = 0; /* * As long as we have interrupts outstanding, go through the @@ -549,10 +550,26 @@ restart: } /* - * If we detect an interrupt storm, pause with the - * source masked until the next hardclock tick. + * Interrupt storm handling: + * + * If this interrupt source is currently storming, + * then throttle it to only fire the handler once + * per clock tick. Each second we go out of storming + * mode to see if the storm has subsided. + * + * If this interrupt source is not currently + * storming, but the number of back to back + * interrupts exceeds the storm threshold, then + * enter storming mode. */ - if (intr_storm_threshold != 0 && + if (storming) { + tsleep(&count, td->td_priority, "istorm", 1); + if (count > hz) { + storming = 0; + count = 0; + } else + count++; + } else if (intr_storm_threshold != 0 && count >= intr_storm_threshold) { if (!warned) { printf( @@ -560,7 +577,7 @@ restart: p->p_comm); warned = 1; } - tsleep(&count, td->td_priority, "istorm", 1); + storming = 1; count = 0; } else count++; @@ -580,6 +597,7 @@ restart: if (!ithd->it_need) { TD_SET_IWAIT(td); count = 0; + storming = 0; CTR2(KTR_INTR, "%s: pid %d: done", __func__, p->p_pid); mi_switch(SW_VOL, NULL); CTR2(KTR_INTR, "%s: pid %d: resumed", __func__, p->p_pid); |
