nits

1 files changed, 5 insertions, 9 deletions

diff --git a/proc.c b/proc.c
index eca5e97..401188e 100644
--- a/proc.c
+++ b/proc.c
@@ -38,8 +38,6 @@ setupsegs(struct proc *p)
     c->ts.esp0 = 0xffffffff;
   }
 
-  // XXX it may be wrong to modify the current segment table!
-
   c->gdt[0] = SEG_NULL;
   c->gdt[SEG_KCODE] = SEG(STA_X|STA_R, 0, 0x100000 + 64*1024, 0); // xxx
   c->gdt[SEG_KDATA] = SEG(STA_W, 0, 0xffffffff, 0);
@@ -96,7 +94,7 @@ copyproc(struct proc* p)
   np->ppid = p->pid;
   release(&proc_table_lock);
 
-  // Copy process image memory.
+  // Copy user memory.
   np->sz = p->sz;
   np->mem = kalloc(np->sz);
   if(np->mem == 0){
@@ -214,18 +212,16 @@ sched(void)
 void
 yield(void)
 {
-  struct proc *p;
+  struct proc *p = curproc[cpu()];
 
-  if((p=curproc[cpu()]) == 0 || curproc[cpu()]->state != RUNNING)
-    panic("yield");
   acquire(&proc_table_lock);
   p->state = RUNNABLE;
   sched();
   release(&proc_table_lock);
 }
 
-// A process's very first scheduling by scheduler()
-// will longjmp here to do the first jump into user space.
+// A fork child's very first scheduling by scheduler()
+// will longjmp here. "return" to user space.
 void
 forkret(void)
 {
@@ -371,7 +367,7 @@ proc_wait(void)
 
   acquire(&proc_table_lock);
   for(;;){
-    // Scan through table looking zombie children.
+    // Scan through table looking for zombie children.
     havekids = 0;
     for(i = 0; i < NPROC; i++){
       p = &proc[i];