APIC IDs may not be consecutive and start from zero, so we cannot really use it

as a direct index into cpus.  Record apicid in struct cpu and have cpunum() look
for it. Replace cpu->id with cpunum() everywhere, and replace cpu->id with cpu->apicid.
Thanks to Xi Wang.

1 files changed, 4 insertions, 4 deletions

diff --git a/trap.c b/trap.c
index 20ae62d..e6b3784 100644
--- a/trap.c
+++ b/trap.c
@@ -48,7 +48,7 @@ trap(struct trapframe *tf)
 
   switch(tf->trapno){
   case T_IRQ0 + IRQ_TIMER:
-    if(cpu->id == 0){
+    if(cpunum() == 0){
       acquire(&tickslock);
       ticks++;
       wakeup(&ticks);
@@ -74,7 +74,7 @@ trap(struct trapframe *tf)
   case T_IRQ0 + 7:
   case T_IRQ0 + IRQ_SPURIOUS:
     cprintf("cpu%d: spurious interrupt at %x:%x\n",
-            cpu->id, tf->cs, tf->eip);
+            cpunum(), tf->cs, tf->eip);
     lapiceoi();
     break;
 
@@ -83,13 +83,13 @@ trap(struct trapframe *tf)
     if(proc == 0 || (tf->cs&3) == 0){
       // In kernel, it must be our mistake.
       cprintf("unexpected trap %d from cpu %d eip %x (cr2=0x%x)\n",
-              tf->trapno, cpu->id, tf->eip, rcr2());
+              tf->trapno, cpunum(), tf->eip, rcr2());
       panic("trap");
     }
     // In user space, assume process misbehaved.
     cprintf("pid %d %s: trap %d err %d on cpu %d "
             "eip 0x%x addr 0x%x--kill proc\n",
-            proc->pid, proc->name, tf->trapno, tf->err, cpu->id, tf->eip,
+            proc->pid, proc->name, tf->trapno, tf->err, cpunum(), tf->eip,
             rcr2());
     proc->killed = 1;
   }