diff options
Diffstat (limited to 'sys/kern/kern_clock.c')
| -rw-r--r-- | sys/kern/kern_clock.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/sys/kern/kern_clock.c b/sys/kern/kern_clock.c index 74f346e..b021580 100644 --- a/sys/kern/kern_clock.c +++ b/sys/kern/kern_clock.c @@ -154,6 +154,7 @@ hardclock(frame) register struct clockframe *frame; { register struct proc *p; + int need_softclock = 0; p = curproc; if (p != idleproc) { @@ -187,16 +188,25 @@ hardclock(frame) statclock(frame); tc_windup(); - ticks++; /* * Process callouts at a very low cpu priority, so we don't keep the * relatively high clock interrupt priority any longer than necessary. */ + mtx_enter(&callout_lock, MTX_SPIN); + ticks++; if (TAILQ_FIRST(&callwheel[ticks & callwheelmask]) != NULL) { - sched_swi(softclock_ih, SWI_NOSWITCH); + need_softclock = 1; } else if (softticks + 1 == ticks) ++softticks; + mtx_exit(&callout_lock, MTX_SPIN); + + /* + * sched_swi acquires sched_lock, so we don't want to call it with + * callout_lock held; incorrect locking order. + */ + if (need_softclock) + sched_swi(softclock_ih, SWI_NOSWITCH); } /* |
