[src/trunk]: src/sys/kern Added a malloc freelist sanity check function, for ...

[manu <manu%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/3c94a2b6cbce
branches:  trunk
changeset: 550991:3c94a2b6cbce
user:      manu <manu%NetBSD.org@localhost>
date:      Tue Aug 26 21:48:53 2003 +0000

description:
Added a malloc freelist sanity check function, for debugging purposes

diffstat:

 sys/kern/kern_malloc.c |  46 ++++++++++++++++++++++++++++++++++++++++++++--
 1 files changed, 44 insertions(+), 2 deletions(-)

diffs (64 lines):

diff -r d45f8b302011 -r 3c94a2b6cbce sys/kern/kern_malloc.c
--- a/sys/kern/kern_malloc.c    Tue Aug 26 21:14:08 2003 +0000
+++ b/sys/kern/kern_malloc.c    Tue Aug 26 21:48:53 2003 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: kern_malloc.c,v 1.81 2003/08/07 16:31:46 agc Exp $     */
+/*     $NetBSD: kern_malloc.c,v 1.82 2003/08/26 21:48:53 manu Exp $    */
 
 /*
  * Copyright (c) 1987, 1991, 1993
@@ -66,7 +66,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_malloc.c,v 1.81 2003/08/07 16:31:46 agc Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_malloc.c,v 1.82 2003/08/26 21:48:53 manu Exp $");
 
 #include "opt_lockdebug.h"
 
@@ -903,3 +903,45 @@
 #endif /* KMEMSTATS */
 }
 #endif /* DDB */
+
+
+#if 0
+/* 
+ * Diagnostic messages about "Data modified on
+ * freelist" indicate a memory corruption, but
+ * they do not help tracking it down.
+ * This function can be called at various places 
+ * to sanity check malloc's freelist and discover
+ * where does the corruption take place.
+ */
+int
+freelist_sanitycheck(void) {
+       int i,j;
+       struct kmembuckets *kbp;
+       struct freelist *freep;
+       int rv = 0;
+               
+       for (i = MINBUCKET; i <= MINBUCKET + 15; i++) {
+               kbp = &bucket[i];       
+               freep = (struct freelist *)kbp->kb_next;
+               j = 0;
+               while(freep) {
+                       vm_map_lock(kmem_map);
+                       rv = uvm_map_checkprot(kmem_map, (vaddr_t)freep,
+                           (vaddr_t)freep + sizeof(struct freelist), 
+                           VM_PROT_WRITE);
+                       vm_map_unlock(kmem_map);
+
+                       if ((rv == 0) || (*(int *)freep != WEIRD_ADDR)) {
+                               printf("bucket %i, chunck %d at %p modified\n",
+                                   i, j, freep);
+                               return 1;
+                       }
+                       freep = (struct freelist *)freep->next;
+                       j++;
+               }
+       }
+
+       return 0;
+}
+#endif