1 files changed, 53 insertions, 21 deletions

diff --git a/kernel/lockdep_internals.h b/kernel/lockdep_internals.h
index a2ee95ad1313..8d7d4b6c741a 100644
--- a/kernel/lockdep_internals.h
+++ b/kernel/lockdep_internals.h
@@ -110,29 +110,61 @@ lockdep_count_backward_deps(struct lock_class *class)
 #endif
 
 #ifdef CONFIG_DEBUG_LOCKDEP
+
+#include <asm/local.h>
 /*
- * Various lockdep statistics:
+ * Various lockdep statistics.
+ * We want them per cpu as they are often accessed in fast path
+ * and we want to avoid too much cache bouncing.
  */
-extern atomic_t chain_lookup_hits;
-extern atomic_t chain_lookup_misses;
-extern atomic_t hardirqs_on_events;
-extern atomic_t hardirqs_off_events;
-extern atomic_t redundant_hardirqs_on;
-extern atomic_t redundant_hardirqs_off;
-extern atomic_t softirqs_on_events;
-extern atomic_t softirqs_off_events;
-extern atomic_t redundant_softirqs_on;
-extern atomic_t redundant_softirqs_off;
-extern atomic_t nr_unused_locks;
-extern atomic_t nr_cyclic_checks;
-extern atomic_t nr_cyclic_check_recursions;
-extern atomic_t nr_find_usage_forwards_checks;
-extern atomic_t nr_find_usage_forwards_recursions;
-extern atomic_t nr_find_usage_backwards_checks;
-extern atomic_t nr_find_usage_backwards_recursions;
-# define debug_atomic_inc(ptr)          atomic_inc(ptr)
-# define debug_atomic_dec(ptr)          atomic_dec(ptr)
-# define debug_atomic_read(ptr)         atomic_read(ptr)
+struct lockdep_stats {
+        int     chain_lookup_hits;
+        int     chain_lookup_misses;
+        int     hardirqs_on_events;
+        int     hardirqs_off_events;
+        int     redundant_hardirqs_on;
+        int     redundant_hardirqs_off;
+        int     softirqs_on_events;
+        int     softirqs_off_events;
+        int     redundant_softirqs_on;
+        int     redundant_softirqs_off;
+        int     nr_unused_locks;
+        int     nr_cyclic_checks;
+        int     nr_cyclic_check_recursions;
+        int     nr_find_usage_forwards_checks;
+        int     nr_find_usage_forwards_recursions;
+        int     nr_find_usage_backwards_checks;
+        int     nr_find_usage_backwards_recursions;
+};
+
+DECLARE_PER_CPU(struct lockdep_stats, lockdep_stats);
+
+#define debug_atomic_inc(ptr)                   {               \
+        struct lockdep_stats *__cpu_lockdep_stats;              \
+                                                                \
+        WARN_ON_ONCE(!irqs_disabled());                         \
+        __cpu_lockdep_stats = &__get_cpu_var(lockdep_stats);    \
+        __cpu_lockdep_stats->ptr++;                             \
+}
+
+#define debug_atomic_dec(ptr)                   {               \
+        struct lockdep_stats *__cpu_lockdep_stats;              \
+                                                                \
+        WARN_ON_ONCE(!irqs_disabled());                         \
+        __cpu_lockdep_stats = &__get_cpu_var(lockdep_stats);    \
+        __cpu_lockdep_stats->ptr--;                             \
+}
+
+#define debug_atomic_read(ptr)          ({                              \
+        struct lockdep_stats *__cpu_lockdep_stats;                      \
+        unsigned long long __total = 0;                                 \
+        int __cpu;                                                      \
+        for_each_possible_cpu(__cpu) {                                  \
+                __cpu_lockdep_stats = &per_cpu(lockdep_stats, __cpu);   \
+                __total += __cpu_lockdep_stats->ptr;                    \
+        }                                                               \
+        __total;                                                        \
+})
 #else
 # define debug_atomic_inc(ptr)          do { } while (0)
 # define debug_atomic_dec(ptr)          do { } while (0)