Re: [RT] lockdep munching nr_list_entries like popcorn

Sebastian Andrzej Siewior
2017-02-16T14:53:55Z

On 2017-02-16 15:42:59 [+0100], Mike Galbraith wrote:
>
> Weeell, I'm trying to cobble something kinda like that together using
> __RT_SPIN_INITIALIZER() instead, but seems mean ole Mr. Compiler NAKs
> the PER_CPU_DEP_MAP_INIT() thingy.
>
> CC mm/swap.o
> mm/swap.c:54:689: error: braced-group within expression allowed only
> inside a function

so this is what I have now. I need to get the `static' symbol working
again and PER_CPU_DEP_MAP_INIT but aside from that it seems to do its
job.

diff --git a/include/linux/locallock.h b/include/linux/locallock.h
index 845c77f1a5ca..36201b37012d 100644
--- a/include/linux/locallock.h
+++ b/include/linux/locallock.h
@@ -22,9 +22,27 @@ struct local_irq_lock {
unsigned long flags;
};

+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+#define PER_CPU_DEP_MAP_INIT(lockname) \
+ .dep_map = { \
+ .key = ({ static struct lock_class_key __key; &__key }),\
+ .name = #lockname, \
+ }
+#else
+#define PER_CPU_DEP_MAP_INIT(lockname)
+#endif
+
#define DEFINE_LOCAL_IRQ_LOCK(lvar) \
+ struct lock_class_key lvar##__key; \
DEFINE_PER_CPU(struct local_irq_lock, lvar) = { \
- .lock = __SPIN_LOCK_UNLOCKED((lvar).lock) }
+ .lock = { \
+ .lock = __RT_SPIN_INITIALIZER(lvar.lock), \
+ .dep_map = { \
+ .key = &lvar##__key, \
+ .name = #lvar, \
+ } \
+ } \
+ }

#define DECLARE_LOCAL_IRQ_LOCK(lvar) \
DECLARE_PER_CPU(struct local_irq_lock, lvar)

> -Mike

Sebastian