Debugging code to help me find places where I forget to call destroylock

bc470986 · Silas Boyd-Wickizer · 1c3d2bb6 · bc470986 · bc470986 · bc470986
--- a/kalloc.c
+++ b/kalloc.c
@@ -136,9 +136,12 @@ kfree_pool(struct kmem *m, char *v)
  if (memsize(v) == -1ull)
    panic("kfree_pool: unknown region %p", v);
-  // Fill with junk to catch dangling refs.
+  if (kinited && m->size <= 16384) {
-  if (kinited && kalloc_memset && m->size <= 16384)
+    verifyfree(v, m->size);
-    memset(v, 1, m->size);
+    // Fill with junk to catch dangling refs.
+    if (kalloc_memset)
+      memset(v, 1, m->size);
+  }
  acquire(&m->lock);
  r = (struct run*)v;
@@ -289,3 +292,20 @@ ksfree(slab_t slab, void *v)
 {
  kfree_pool(slabmem[slab], v);
 }
+void
+verifyfree(char *ptr, u64 nbytes)
+{
+#if VERIFYFREE
+  char *e = ptr + nbytes;
+  for (; ptr < e; ptr++) {
+    // Search for pointers in the ptr region
+    u64 x = *(uptr *)ptr;
+    if (KBASE < x && x < KBASE+(128ull<<30)) {
+      struct klockstat *kls = (struct klockstat *) x;
+      if (kls->magic == LOCKSTAT_MAGIC)
+        panic("verifyunmarked: LOCKSTAT_MAGIC %p:%lu", ptr, nbytes);
+    }
+  }
+#endif
+}
--- a/kernel.h
+++ b/kernel.h
@@ -154,7 +154,7 @@ void*           kmalloc(u64);
 void            kmfree(void*);
 int             kmalign(void **p, int align, u64 size);
 void            kmalignfree(void *);
+void            verifyfree(char *ptr, u64 nbytes);
 // kbd.c
 void            kbdintr(void);

--- a/kmalloc.c
+++ b/kmalloc.c
@@ -102,6 +102,7 @@ kmfree(void *ap)
  b = (long) h->next;
  if(b < 0 || b > KMMAX)
    panic("kmfree bad bucket");
+  verifyfree(ap, 1 << b);
  h->next = freelists[c].buckets[b];
  freelists[c].buckets[b] = h;