Merge tag 'gvt-fixes-2018-07-03' of https://github.com/intel/gvt-linux into drm-intel...

[linux.git] / lib / stackdepot.c

diff --git a/lib/stackdepot.c b/lib/stackdepot.c
index 60f77f1d470a0589ccdeacbb52a9eb45a8a1cec1..e513459a5601a5d19a5ad7461d8b137cd2d7a469 100644 (file)
--- a/lib/stackdepot.c
+++ b/lib/stackdepot.c
@@ -50,7 +50,7 @@
                                        STACK_ALLOC_ALIGN)
 #define STACK_ALLOC_INDEX_BITS (DEPOT_STACK_BITS - \
                STACK_ALLOC_NULL_PROTECTION_BITS - STACK_ALLOC_OFFSET_BITS)
-#define STACK_ALLOC_SLABS_CAP 1024
+#define STACK_ALLOC_SLABS_CAP 8192
 #define STACK_ALLOC_MAX_SLABS \
        (((1LL << (STACK_ALLOC_INDEX_BITS)) < STACK_ALLOC_SLABS_CAP) ? \
         (1LL << (STACK_ALLOC_INDEX_BITS)) : STACK_ALLOC_SLABS_CAP)
@@ -163,6 +163,21 @@ static inline u32 hash_stack(unsigned long *entries, unsigned int size)
                               STACK_HASH_SEED);
 }
 
+/* Use our own, non-instrumented version of memcmp().
+ *
+ * We actually don't care about the order, just the equality.
+ */
+static inline
+int stackdepot_memcmp(const unsigned long *u1, const unsigned long *u2,
+                       unsigned int n)
+{
+       for ( ; n-- ; u1++, u2++) {
+               if (*u1 != *u2)
+                       return 1;
+       }
+       return 0;
+}
+
 /* Find a stack that is equal to the one stored in entries in the hash */
 static inline struct stack_record *find_stack(struct stack_record *bucket,
                                             unsigned long *entries, int size,
@@ -173,10 +188,8 @@ static inline struct stack_record *find_stack(struct stack_record *bucket,
        for (found = bucket; found; found = found->next) {
                if (found->hash == hash &&
                    found->size == size &&
-                   !memcmp(entries, found->entries,
-                           size * sizeof(unsigned long))) {
+                   !stackdepot_memcmp(entries, found->entries, size))
                        return found;
-               }
        }
        return NULL;
 }
@@ -192,6 +205,7 @@ void depot_fetch_stack(depot_stack_handle_t handle, struct stack_trace *trace)
        trace->entries = stack->entries;
        trace->skip = 0;
 }
+EXPORT_SYMBOL_GPL(depot_fetch_stack);
 
 /**
  * depot_save_stack - save stack in a stack depot.
@@ -283,3 +297,4 @@ depot_stack_handle_t depot_save_stack(struct stack_trace *trace,
 fast_exit:
        return retval;
 }
+EXPORT_SYMBOL_GPL(depot_save_stack);