a few nits

passes all tests on two-processor smp

a few nits
af03ab14 · Frans Kaashoek · b364c4b8 · af03ab14 · af03ab14 · af03ab14
--- a/bio.c
+++ b/bio.c
@@ -109,7 +109,6 @@ bread(uint dev, uint sector)
 void
 bwrite(struct buf *b)
 {
-  cprintf("bwrite sector %d\n", b->sector);
  if((b->flags & B_BUSY) == 0)
    panic("bwrite");
  b->flags |= B_DIRTY;

--- a/exec.c
+++ b/exec.c
@@ -102,7 +102,7 @@ exec(char *path, char **argv)
  return 0;

 bad:
-  freevm(pgdir);
+  if (pgdir) freevm(pgdir);
  iunlockput(ip);
  return -1;
 }
--- a/kalloc.c
+++ b/kalloc.c
@@ -111,8 +111,6 @@ kalloc(int n)
    }
  }
  release(&kmem.lock);
-
-  cprintf("kalloc: out of memory\n");
  return 0;
 }