1 files changed, 25 insertions, 6 deletions

diff --git a/proc.c b/proc.c
index 1c705e9..d060445 100644
--- a/proc.c
+++ b/proc.c
@@ -9,7 +9,6 @@
 struct spinlock proc_table_lock;
 
 struct proc proc[NPROC];
-struct proc *curproc[NCPU];
 static struct proc *initproc;
 
 int nextpid = 1;
@@ -61,6 +60,7 @@ growproc(int n)
   cp->mem = newmem;
   kfree(oldmem, cp->sz);
   cp->sz += n;
+  setupsegs(cp);
   return cp->sz - n;
 }
 
@@ -71,6 +71,7 @@ setupsegs(struct proc *p)
 {
   struct cpu *c;
   
+  splhi();
   c = &cpus[cpu()];
   c->ts.ss0 = SEG_KDATA << 3;
   if(p)
@@ -93,6 +94,7 @@ setupsegs(struct proc *p)
 
   lgdt(c->gdt, sizeof(c->gdt));
   ltr(SEG_TSS << 3);
+  spllo();
 }
 
 // Create a new process copying p as the parent.
@@ -176,6 +178,19 @@ userinit(void)
   initproc = p;
 }
 
+// Return currently running process.
+// XXX comment better
+struct proc*
+curproc(void)
+{
+  struct proc *p;
+
+  splhi();
+  p = cpus[cpu()].curproc;
+  spllo();
+  return p;
+}
+
 //PAGEBREAK: 42
 // Per-CPU process scheduler.
 // Each CPU calls scheduler() after setting itself up.
@@ -188,12 +203,14 @@ void
 scheduler(void)
 {
   struct proc *p;
+  struct cpu *c;
   int i;
 
   for(;;){
     // Loop over process table looking for process to run.
     acquire(&proc_table_lock);
-
+    
+    c = &cpus[cpu()];
     for(i = 0; i < NPROC; i++){
       p = &proc[i];
       if(p->state != RUNNABLE)
@@ -202,14 +219,14 @@ scheduler(void)
       // Switch to chosen process.  It is the process's job
       // to release proc_table_lock and then reacquire it
       // before jumping back to us.
-      cp = p;
+      c->curproc = p;
       setupsegs(p);
       p->state = RUNNING;
-      swtch(&cpus[cpu()].context, &p->context);
+      swtch(&c->context, &p->context);
 
       // Process is done running for now.
       // It should have changed its p->state before coming back.
-      cp = 0;
+      c->curproc = 0;
       setupsegs(0);
     }
 
@@ -222,11 +239,13 @@ scheduler(void)
 void
 sched(void)
 {
+  if(read_eflags()&FL_IF)
+    panic("sched interruptible");
   if(cp->state == RUNNING)
     panic("sched running");
   if(!holding(&proc_table_lock))
     panic("sched proc_table_lock");
-  if(cpus[cpu()].nlock != 1)
+  if(cpus[cpu()].nsplhi != 1)
     panic("sched locks");
 
   swtch(&cp->context, &cpus[cpu()].context);