SLUB: support slub_debug on by default

[mirror_ubuntu-bionic-kernel.git] / mm / slub.c

diff --git a/mm/slub.c b/mm/slub.c
index e0cf6213abc0fcfcd403c5d9ad0da079ad2214f9..6aea48942c29b3e2ada3a551d5382cc88e474539 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -323,7 +323,11 @@ static inline int slab_index(void *p, struct kmem_cache *s, void *addr)
 /*
  * Debug settings:
  */
+#ifdef CONFIG_SLUB_DEBUG_ON
+static int slub_debug = DEBUG_DEFAULT_FLAGS;
+#else
 static int slub_debug;
+#endif
 
 static char *slub_debug_slabs;
 
@@ -888,38 +892,57 @@ fail:
 
 static int __init setup_slub_debug(char *str)
 {
-       if (!str || *str != '=')
-               slub_debug = DEBUG_DEFAULT_FLAGS;
-       else {
-               str++;
-               if (*str == 0 || *str == ',')
-                       slub_debug = DEBUG_DEFAULT_FLAGS;
-               else
-               for( ;*str && *str != ','; str++)
-                       switch (*str) {
-                       case 'f' : case 'F' :
-                               slub_debug |= SLAB_DEBUG_FREE;
-                               break;
-                       case 'z' : case 'Z' :
-                               slub_debug |= SLAB_RED_ZONE;
-                               break;
-                       case 'p' : case 'P' :
-                               slub_debug |= SLAB_POISON;
-                               break;
-                       case 'u' : case 'U' :
-                               slub_debug |= SLAB_STORE_USER;
-                               break;
-                       case 't' : case 'T' :
-                               slub_debug |= SLAB_TRACE;
-                               break;
-                       default:
-                               printk(KERN_ERR "slub_debug option '%c' "
-                                       "unknown. skipped\n",*str);
-                       }
+       slub_debug = DEBUG_DEFAULT_FLAGS;
+       if (*str++ != '=' || !*str)
+               /*
+                * No options specified. Switch on full debugging.
+                */
+               goto out;
+
+       if (*str == ',')
+               /*
+                * No options but restriction on slabs. This means full
+                * debugging for slabs matching a pattern.
+                */
+               goto check_slabs;
+
+       slub_debug = 0;
+       if (*str == '-')
+               /*
+                * Switch off all debugging measures.
+                */
+               goto out;
+
+       /*
+        * Determine which debug features should be switched on
+        */
+       for ( ;*str && *str != ','; str++) {
+               switch (tolower(*str)) {
+               case 'f':
+                       slub_debug |= SLAB_DEBUG_FREE;
+                       break;
+               case 'z':
+                       slub_debug |= SLAB_RED_ZONE;
+                       break;
+               case 'p':
+                       slub_debug |= SLAB_POISON;
+                       break;
+               case 'u':
+                       slub_debug |= SLAB_STORE_USER;
+                       break;
+               case 't':
+                       slub_debug |= SLAB_TRACE;
+                       break;
+               default:
+                       printk(KERN_ERR "slub_debug option '%c' "
+                               "unknown. skipped\n",*str);
+               }
        }
 
+check_slabs:
        if (*str == ',')
                slub_debug_slabs = str + 1;
+out:
        return 1;
 }