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do not call proc_exit until lock dropped

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rsc 2007-08-28 04:20:13 +00:00
parent 1baead533f
commit 4c917f6df2
1 changed files with 18 additions and 20 deletions
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22
trap.c
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@ -76,29 +76,27 @@ trap(struct trapframe *tf)
break; break;
default: default:
if(cp) { if(cp == 0) {
// Assume process divided by zero or dereferenced null, etc.
cprintf("pid %d %s: trap %d err %d on cpu %d eip %x -- kill proc\n",
cp->pid, cp->name, tf->trapno, tf->err, cpu(), tf->eip);
proc_exit();
}
// Otherwise it's our mistake. // Otherwise it's our mistake.
cprintf("unexpected trap %d from cpu %d eip %x\n", cprintf("unexpected trap %d from cpu %d eip %x\n",
tf->trapno, cpu(), tf->eip); tf->trapno, cpu(), tf->eip);
panic("trap"); panic("trap");
} }
// Assume process divided by zero or dereferenced null, etc.
cprintf("pid %d %s: trap %d err %d on cpu %d eip %x -- kill proc\n",
cp->pid, cp->name, tf->trapno, tf->err, cpu(), tf->eip);
cp->killed = 1;
}
cpus[cpu()].nlock--; cpus[cpu()].nlock--;
if(tf->trapno == IRQ_OFFSET + IRQ_TIMER && cp != 0){
// Force process exit if it has been killed and is in user space. // Force process exit if it has been killed and is in user space.
// (If it is still executing in the kernel, let it keep running // (If it is still executing in the kernel, let it keep running
// until it gets to the regular system call return.) // until it gets to the regular system call return.)
if((tf->cs&3) == DPL_USER && cp->killed) if(cp && cp->killed && (tf->cs&3) == DPL_USER)
proc_exit(); proc_exit();
// Force process to give up CPU and let others run. // Force process to give up CPU on clock tick.
// If locks were held with interrupts on, would need to check nlock. // If interrupts were on while locks held, would need to check nlock.
if(cp->state == RUNNING) if(cp && cp->state == RUNNING && tf->trapno == IRQ_OFFSET+IRQ_TIMER)
yield(); yield();
} }
}